text:
En savoir plus à propos de l'abonnement Scribd
Découvrez tout ce que Scribd a à offrir, dont les livres et les livres audio des principaux éditeurs.
NOTE: Read the entire instruction manual before starting the SAFETY CONSIDERATIONSinstallation. Improper installation, adjustment, alteration, service, maintenance, TABLE OF CONTENTS or use can cause explosion, fire, electrical shock, or other PAGE conditions which may cause death, personal injury or property damage. Consult a qualified installer, service agency, or yourTABLE OF CONTENTS . . . . . . . . . . . . . . . . . . . . . . . . . . 1 distributor or branch for information or assistance. The qualifiedSAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . 1 installer or agency must use factory−authorized kits or accessoriesINTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 when modifying this product. Refer to the individual instructions packaged with kits or accessories when installing.FAN COIL DESCRIPTIONAND TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . 2 Follow all safety codes. Wear safety glasses, protective clothing and work gloves. Have a fire extinguisher available. Read these FY5, FH4, PF4 (EVEN SIZES) instructions thoroughly and follow all warnings or cautions AND FF1E (EVEN SIZES), . . . . . . . . . . . . . . . . . . . 2 included in literature and attached to the unit. Consult local FB4C, FX4D, PF4, FF1E, AND FZ (ODD SIZES) . . . 5 building codes and the current editions of the National Electrical FV4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Code (NEC) NFPA 70.MOTOR AND MODULES . . . . . . . . . . . . . . . . . . . . . . . . 8 In Canada, refer to the current editions of the Canadian ElectricalCONNECTIONS AND CONNECTORS (FK4, FV4) . . . . 9 Code CSA C22.1.TYPICAL OPERATING MODES . . . . . . . . . . . . . . . . . . . 9 Recognize safety information. This is the safety−alert symbol . FV4 MOTOR CONTROL TEST VALUES (WITH When you see this symbol on the unit and in instruction manuals, 16−PIN CONNECTOR AT MOTOR UNPLUGGED) 12 be alert to the potential for personal injury. FE4 SELF−IDENTIFYING RESISTOR VALUES . . . 15 Understand the signal words DANGER, WARNING, and CAUTION. These words are used with the safety−alert symbol. FFM AND FMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 DANGER identifies the most serious hazards which will result inSPEED TAP AND DELAY−OFF TIME . . . . . . . . . . . . . . 18 severe personal injury or death. WARNING signifies hazards FFM AND FMA4P . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 which could result in personal injury or death. CAUTION is used FMA4X . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 to identify unsafe practices which may result in minor personal injury or product and property damage. NOTE is used to highlightELECTRIC HEATER FUNCTION suggestions which will result in enhanced installation, reliability, or AND TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . 24 operation. FB4, FE4, FF1E, FH4, FV4, FX4, FZ AND PF4 . . . . . 24 FFM AND FMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . .CARE AND MAINTENANCE . . . . . . . . . . . . . . . . . . . . . 24 25 ! WARNING FB4, FE4, FH4, FV4, FX4, FZ4 AND PF4 . . . . . . . . . 25 UNIT OPERATION AND SAFERTY HAZARD FF1E, FFMA, FMA . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Failure to follow this warning could result in personal injury or death.REFRIGERANT FLOW−CONTROL DEVICES . . . . . . . 27ALUMINUM COIL REPAIR . . . . . . . . . . . . . . . . . . . . . . . 29 Puron (R−410A) systems operate at higher pressures than R−22 systems. Do not use R−22 service equipment orPRE−INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 components on R−410 equipment. Ensure service equipmentOLD COPPER OR TIN−PLATED COILS WITH TXV . . 29 is rated for R−410.OLD ALL−ALUMINUM COILS WITH TXV . . . . . . . . . 30INSTALLATION− A−COIL UNITS ONLY . . . . . . . . . . . . 30INSTALLATION − SLOPE COIL UNITS ONLY . . . . . . . 31 INTRODUCTION The "F" and "PF" series fan coil units are designed for flexibility in a variety of applications that meet upflow, horizontal, or downflow requirements. Units are available in 1−1/2 through 5 ton nominal cooling capacities. Factory−authorized, field−installed electric heater packages are available in 3 through 30 kilowatts. 1FMA4X, FMA4P Fan Coils are designed with application CLEANING OR REPLACING REFRIGERANTflexibility in mind and are suitable for closet and flush mount FLOW−CONTROL DEVICEinstallations. Units are available with field−installed electric heat Refer to Fig. 26 and instructions given in "Piston Body Cleaningwith circuit breaker. Units are used indoors as the fan coil for or Replacement" section.split−system heat pumps or air conditioners. The FMA4P uses arefrigerant piston metering device and a 3 speed PSC Motor. The refrigerant flow−control device is protected by a wire meshFMA4X uses a TXV and a 5 speed multi−tap ECM Motor for strainer. It is located inside the 3/8−in. liquid tube at field brazeefficiency. Units are available in 18,000 through 36,000 Btuh joint next to flow−control device. Access to strainer is through fieldnominal cooling capacities. braze joint.NOTE: Nuisance sweating may occur if the unit is installed in a SEQUENCE OF OPERATIONhumid location with low airflow. A. Condensing UnitUnits are designed for upflow application only. Local codes may COOLINGlinit this free−air−return type unit to installation in single−levelapplications. When thermostat calls for cooling, the circuit between R and G is complete and single−pole single−throw relay FR is energized. The normally open contacts close causing blower to operate.
2Unit Functions fan will also turn off, providing thermostat is not calling for A. Transformer the fan. 1. Proper Wiring of Transformer Primary or High Side 3. E Yellow wire from Molex plug is wired to C terminal on When thermostat sends a signal to E, a 24−Vac signal is sent transformer and black wire from PCB relay (normally− to sequencer/relay No. 3. The 24−Vac signal applied to se- open) terminal is wired to 208−V or 230−V terminal on quencer/relay No. 3 turns on third stage of electric heat. The transformer. Units are factory wired at 230−V terminal. 24−Vac signal applied to sequencer/relay No. 1 turns on first stage of electric heat and fan. When thermostat stops 2. Proper Wiring of Transformer Secondary or 24−V Side calling for electric heat, the signal to sequencers/relays 1, 2, Red wire of transformer is wired to T terminal on PCB and and 3 are turned off, and sequencers/relays open. This brown wire of transformer is wired to C terminal on PCB. causes electric heat to turn off with fan, providing thermo-NOTE: T terminal on PCB is used to protect the transformer. T stat is not calling for the fan.terminal is connected through the fuse to R terminal on PCB. NOTE: Electric heaters are factory wired with all stages tied B. Indoor Fan together. If independent staging is desired, consult outdoor 1. Wiring thermostat installation instructions, or corporate thermostat Indoor fan motor yellow lead is wired to C terminal on instructions. transformer. The red, blue, or black speed lead is wired to TROUBLESHOOTING THE PRINTED CIRCUIT BOARD SPT terminal on fan relay part of PCB. Units are factory wired on medium speed (blue lead connected). (CES013000−00, 01 / HK61EA002 / HK61EA006)NOTE: Unused fan speed leads must be capped or taped off to Use wiring schematics shown in Fig. 1, and Fig. 2 as a guide inprevent direct short to cabinet surface. troubleshooting PCB unless otherwise noted. A. If Fan Will Not Turn On from Thermostat: 2. Functional Control a. Thermostat and Relay Control IF THERE IS NO HIGH VOLTAGE TO TRANSFORMER: When thermostat calls for the fan in cooling, heat pump, 1. Check plug/receptacle connection. This supplies power heating, or fan−only mode, a 24−Vac signal is sent to relay. from heaters to PCB Fan Relay. Be sure plug is connected This causes the relay to close its normally−open contacts, properly. turning on fan. When thermostat no longer calls for the fan, 2. Check sequencer/relay No. 1 and plug wiring. Yellow wire the signal sent to relay is turned off and relay opens causing should be connected to Pin No. 9 of plug and to limit fan to turn off after a 90−second fan−off delay. switch. Black wire should be connected to Pin No. 7 of plug b. Sequencer/Electric Heat Relay Interlock and to sequencer/relay No. 1. The fan will also operate whenever there is a call for electric 3. Check field power leads L1 and L2. If these are not receiv- heat, even if fan relay is not energized. This happens be- ing power, system cannot function. cause fan is interlocked with first stage of electric heat IF TRANSFORMER HAS HIGH VOLTAGE APPLIED TO IT: through the normally−closed contact of fan relay. 1. Check low−voltage transformer leads R (red) and CNOTE: The fan interlock is only connected to first stage electric (brown). Be sure they are wired to correct locations.heat (W2). W3 and E do not contain an interlock with fan. See 2. Check output voltage of transformer secondary side R (red)outdoor thermostat installation instructions when electric heat and C (brown). Be sure transformer output is betweenstaging is desired. 18Vac and 30Vac. If transformer output is incorrect and C. Electric Heat transformer is receiving correct input voltage (208V orWhen thermostat calls for electric heat, a 24−Vac signal is sent to 230V), then transformer needs to be replaced with recom-sequencer/heat relay through W2, causing first stage to turn on. W3 mended transformer. If no problem exists with transformerand E also receive signal if wired in with W2. If W3 and E are not secondary, proceed to items 3 and 4.wired to W2, the sequencers/heat relays can be controlled 3. Check low−voltage fuse shown in Fig. 1 or Fig. 2. If fuse isindividually to stage additional electric heat. The sequence control blown, replace it with an identical 5−amp fuse. The trans-is described in the following section: former cannot supply power to board with fuse blown or 1. W2 loose. If fuse blows when unit has power applied to it, the When thermostat sends a signal to W2, a 24−Vac signal is system most likely has one of the following problems: applied across sequencer/relay No. 1, causing it to close. a. Check all 24−V wiring for an electrical short. When sequencer/relay No. 1 closes, first stage of electric b. The maximum load on transformer is 40 VA. If load on heat is energized. In straight electric heat, fan is also ener- transformer is excessive, the low−voltage 5−amp fuse will gized through the normally closed contacts of fan relay. In blow to protect transformer. If load exceeds VA rating of cooling, heat pump, or manual fan mode, fan will already transformer, a larger VA rated transformer needs to be in- be running since fan relay would have been energized. stalled. Check sequencers/relays for excessive current When thermostat stops calling for electric heat, the 24−Vac draw. signal to sequencer/relay No. 1 turns off and sequencer c. Check wiring of heaters. If a heater is miswired, fuse may opens after a delay of 60 to 90 seconds. Heaters equipped blow. If a heater is miswired, correct miswiring by compar- with relays will be de−energized immediately. When se- ing it to heater wiring label. quencer/relay opens, first stage of heat turns off along with fan, providing thermostat is not calling for the fan. 4. Check connections on primary side of transformer. If they are not connected properly, the transformer secondary can- 2. W3 not supply the 24−V signal to energize fan relay. If trans- When a signal is sent to W3, a 24−Vac signal to sequencer/ former is receiving correct primary voltage but is not put- relay No. 2 causes it to close, with second stage of electric ting out correct secondary voltage, transformer needs to be heat turning on. The 24−Vac signal applied to sequencer/re- replaced. lay No. 1 causes fan to operate. Timing is such that sequen- cer/relay No. 1 will turn on before sequencer/relay No. 2. B. If Electric Heat Stages Will Not Turn On But Fan Will When signal to W3 is turned off, sequencer/relay No. 2 Turn On: opens. If W2 is also satisfied, first stage of electric heat and IF THERE IS NO HIGH VOLTAGE TO TRANSFORMER:
3 1. Check plug connection between heaters and board. This blows when there is a high current draw on transformer, high supplies power to transformer and fan. Be sure plug is con- voltage applied to low−voltage circuit, or a direct secondary short. nected properly. When there is a high current draw on transformer, it is most likely 2. Check sequencer/relay No. 1 and plug wiring. Yellow wire because transformer has been shorted or system is trying to draw should be connected to Pin No. 9 of plug and to limit more VA than transformer rating allows. When fuse blows because switch. Black wire should be connected to Pin No. 7 of plug of high voltage, the system has mixed high− and low−voltage and to sequencer/relay No. 1. signals. 3. Check incoming high−voltage power leads. If these are not 1. Check wiring of sequencers/relays as shown in Fig. 1 and receiving power, system cannot function. Fig. 2. Be sure transformer is not shorting out because ther- mostat wires are miswired.IF TRANSFORMER HAS VOLTAGE APPLIED TO IT: 2. Check wiring of relays as shown in Fig. 1 And Fig. 2. Be 1. Check low−voltage transformer leads R (red) and C sure low−voltage and high−voltage wiring is correct. (brown). Make sure they are wired to correct location. The unit will not function without proper connections. 3. Check VA draw on transformer. If VA draw is more than VA rating of transformer, fuse will blow. If this is the case, 2. Check output voltage of transformer secondary side R (red) replace transformer with one that has a higher VA rating and and C (brown). If transformer output is low (less than meets system specifications. 18Vac), refer to items 3 and 4 of previous "If Transformer Has High Voltage Applied To It" section. D. If Fan Runs Continuously:IF TRACES ARE OVERHEATED ON BACK OF PCB: 1. If PCB has no low−voltage power, check blue and black fan leads. These may be switched at sequencer/relay.Usually whenever a trace is blown on PCB, it means either therehas been a high−voltage short or high voltage has been applied to 2. If PCB has low−voltage power, check fan relay to see if it islow−voltage circuit. This can be prevented by making sure PCB is opening and closing. It may be stuck in the normally closedwired correctly before PCB has power applied to it. position due to debris in relay. C. If Transformer Fuse Keeps Blowing: E. Transformer Failure:When low−voltage fuse blows, it means transformer would have Check 208−V and 230−V transformer connections. They may beblown if fuse had not been in circuit to protect it. The fuse usually miswired. 1005-161
A97020 Fig. 1 − Fan Coil Printed Circuit Board (CES013003−00, 01 / HK61EA002)
LR40061 A03010 Fig. 2 − Fan Coil Printed Circuit Board (HK61EA006) T-O-D 60TX11
FB4C, FX4D, PF4, FF1E, and FZ (odd sizes) C. Prior to installing the replacement control module, the motor section condition needs to be verified.FAN MOTOR 1. Check to see if the blower wheel spins freely.The multi−speed ECM motor used with this product contains twoparts: the control module and the motor winding section. Do not 2. To check for short to ground, use an ohmmeter to measureassume the motor or module is defective if it will not start. Go the resistance from any one of the motor connector pins tothrough the steps described below before replacing control module the aluminum end plate of the motor. This resistance shouldor entire motor. The control module is available as a replacement be greater than 100,000 ohms.part. 3. Check the motor phase−to−phase resistance between each of A. It is normal for the motor to rock back and forth on startup. Do the leads in the three−pin motor connector. The lead−to− not replace the motor if this is the only problem identified. lead resistance across any two leads should be less than 20 ohms. Each lead−to−lead resistance should be the same B. If the motor is not running: within −/+ 10 percent. 1. Check for proper high voltage and ground at the L,G, and N 4. If any motor fails any of the three tests, do not install a new connections at the motor. Correct any voltage issue before control module. The new control can fail if placed on a de- proceeding to the next step. fective motor. 2. The motor is communicated through 24−Vac signals to the The prior fan coil models with multi−speed ECM blower motors 1,2,3,4,5 and C (common) terminals. Not all taps are pro- used a printed circuit board, similar to the PSC models. The current grammed, if low voltage is applied to an non−programmed fan coils do not use the printed circuit board and rely on the motor terminal, the motor will not operate, which is normal. Verify control programming to provide the off−delay timing. the part number of the motor matches the correct replace- ment motor part number for the unit model number. Another design aspect of the control board was to provide a resistor in the "G" circuit in case a power stealing thermostat was 3. Initiate a demand from the thermostat and check the voltage used. This resistor is no part of the wiring harness, as shown on between C (common) and terminal 1− 5. If voltage is wiring diagram. The resistor is a 2−watt, 1500−ohm resistor. present and the motor isn't operating, then the motor/control module is failed. If the resistor has failed open, a likely cause is due to the power stealing thermostat. Connecting C (common) may resolve the
5issue. Having an open resistor should not affect the operation of themotor.Fan Speed SelectionThe fan speed selection is done at the motor connector. Units withor without electric heaters require a minimum CFM. Refer to the
NAMEPLATE LABELunit wiring label to ensure that the fan speed selected is not lowerthan the minimum fan speed indicated.To change motor speeds disconnect the BLUE fan lead from motorconnector terminal No. 2 (factory default position) and move todesired speed-tap; 1, 2, 3, or 5.Speed-taps 1, 2, and 3 have a 90−second blower off time delaypre-programmed into the motor. Speed-tap 4 is used for electricheat only (with 0 second blower time delay) and the WHITE wireshould remain on tap 4. Speed-tap 5 is used for high staticapplications, but has a 0−second blower time delaypre-programmed into the motor. See Airflow Performance tablesfor actual CFM. Also, see Fig. 4 for motor speed selectionlocation.NOTE: In low static applications, lower motor speed tap shouldbe used to reduce possibility of water being blown off coil. Tap 1 Low 90 sec off delay Tap 2 Medium 90 sec off delay Tap 3 High 90 sec off delay Tap 4 Electric heat † 0 sec off delay Tap 5 Max ‡ 0 sec off delay† electric heat airflow is same CFM as Tap 3, except 0 sec off delay‡ high static applications, see airflow tables for max airflow
1 2 3 4 5
A13028 Fig. 5 − FV4 Motor / ECM5.0 Motor
9 10 11 12 13 14 15 16 1 2 3 4 5 6 7 8
A11048 Fig. 6 − FV4 Motor / ECM2.3 MotorFig. 4 − Motor Speed Selection for FB4C, FX4D, FZ4A & PF4 (odd sizes)
6 FV4 heater size, outdoor unit size and type, comfort or efficiency settings, on and off delay profiles, and continuous fan speed. TheConstant Air Flow installer should select the correct size of components that are beingUnlike fan coils using induction motors where static pressure installed in each installation. If no selections are made, the factoryaffects airflow, these fan coils are constant airflow units. The default settings are for the largest heater, largest outdoor unit, ACblower delivers requested airflow regardless of static pressure. system type, nominal airflow adjust, and 0/90 time delay.Consult fan coil Product Data for static pressure limits. The NOTE: Outdoor unit model should have an AHRI rating with theECM2.3/5.0 is pre−programmed and contains airflow tables for all variable speed fan coil. Some outdoor unit models will not workmodes of operation. Blower characteristics (requested airflow,torque, and speed) are known from laboratory testing If any two properly with this fan coil.characteristics are known, the third is defined. Power for system is supplied from a 230−Vac, 60−Hz line. Class 2Requested airflow is known from Easy Select board configuration voltage (24 Vac nom.), used for thermostat connections, is derivedand thermostat signals. Torque is known because it is directly from transformer located in close proximity to PCB. The 24−Vacrelated to stator current, which is measured by motor control. secondary circuit includes 5−amp automotive−type fuse in SEC2Speed is measured by counting back EMF pulses from stator circuit.windings. This information is entered into an expression that Connection to heater panel is made through 12−pin connectorcalculates torque from speed and airflow numbers. If calculation PL−1. Connections to thermostat are made at screw terminals.does not match stored blower characteristics, torque is adjusted Twenty−one pin terminals comprise field select taps for motor.until agreement is reached. This calculation and adjustment is Fuse Data: 5−amp automotive−type ATC/ATO (tan)performed every 0.8 seconds while motor is in operation. There is 32Vno direct measure of static pressure, but unit does react to a change 200 percent current opening time of five seconds maximumin static to maintain constant airflow. A change in pressure willresult in a change in stator speed and torque. The motor will begin Electrical Connectionsto adjust on the next sampling, calculate new desired speed and Twenty−one 0.110−in pin terminals are used to providetorque, and adjust as necessary. programming selections for operating modes of ECM2.3/5.0. TheINTEGRATED CONTROLS AND MOTOR 6 selection modes are listed below. For additional information, refer to Easy Select Configuration Taps section.ECM2.3/5.0 AUX Heat Range—(Violet Wire)An ECM2.3/5.0 is fed high voltage AC power through the 5−pinconnector. (See Fig. 6 or Fig. 5.) The AC power is then internally AC/HP Size—(Blue Wire) Type—(Orange Wire)rectified to DC by a diode module. After rectification, DC signal is AC/HP CFM Adjust—(Black Wire)electronically communicated and fed in sequential order to three AC/HP Time Delay—(Grey Wire)stator windings. The frequency of these commutation pulses Continuous Fan—(Yellow Wire)determines motor speed. The rotor is permanently magnetized. SEQUENCE OF OPERATION (FV4)An ECM2.3/5.0 is powered with high voltage at all times. Themotor will not run with high voltage alone. Low voltage must be A. Continuous Fan Modeapplied to control plug to run motor. The thermostat closes circuit R to G. The unit delivers the airflowECM2.3/5.0 Control Power selected for fan only operation.The ECM2.3/5.0 control power is supplied from R circuit through B. Cooling Mode—Single Speed or Two−Speed Highprinted circuit runs to motor control Connector−Pin 8, through Thermostat closes circuits R to G, R to Y/Y2 and R to O (heatmotor control harness to motor. The C side of low−voltage control pump only). A circuit R to Y1 is required for two−speed highpower circuit is connected by printed circuit runs to motor operation. Airflow delivered the airflow selected by AC/HP SIZEConnector −Pins 9, 10, and 11 then through motor control harness selection and CFM ADJUST selection.to motor. C. Cooling Mode—Two−Speed LowLow−Voltage Circuit Fusing and Reference Thermostat closes R to G and R to Y1 and R to O (heat pumpThe low−voltage circuit is fused by a board−mounted 5−amp only). Unit delivers two−speed low airflow for AC/HP SIZE andautomotive−type fuse placed in series with transformer SEC2 and CFM ADJUST selected.R circuit. The C circuit of transformer is referenced to chassis D. Cooling + Dehumidify Mode (Thermidistat or Comfortground through a printed circuit run at SEC1 connected to metal Zone II−B and Single−Speed Outdoor Unit Installed)standoff marked. J1 jumper must be pulled from Easy Select Board. Control closesNOTE: The PCB must be mounted with two screws and motor R to G, R to Y/Y2, and R to O (heat pump only) and open R toground lead secured to blower housing or erratic motor operation DH. Dehumidification is active when 24Vac is removed from DHcan result. terminal. Unit delivers 20 percent less airflow.Transformer, Motor, and Electric Heater Power Connection E. SuperDehumidify ModeTransformer high voltage supplied from electric heater package or (Thermidisat or Comfort Zone II−B indoor control,high voltage leads through 12−pin heater connector plug/recp2. Single−Speed Outdoor Unit)The ECM2.3/5.0 power connections are made at the transformer This mode is only activated by the indoor control when COOL toprimary terminals. The transformer secondary connections are DEHUMIDIFY and SUPERDEHUMIDIFY are configured at themade at SEC1 and SEC2 connectors. control and there is a call for dehumidfication without a call forPCB LAYOUT AND DESCRIPTION (FV4) cooling. The control closes R to Y/Y2, R to O (heat pump only) and opens R to DH and R to G. This signals the fan coil to run atNOTE: Layout of actual PCB is depicted in Fig.7. minimum airflow for maximum humidity removal. The controlThe Easy Select Board is the interface between the ECM motor and will cycle the equipment 10 minutes on and 10 minutes off untilother system components. The board offers choices of electric satisfied.
7 Table 1 – Motor and Modules Required Control Module Model Size Motor Type Current Blower Motor P/N Replacement Kit Number FV4B_002 ECM2.3 HD44AE131 RMOD44AE131 FV4B_003 ECM2.3 HD44AE132 RMOD44AE132 FV4B_005 ECM2.3 HD44AE133 RMOD44AE133 FV4B_006 ECM2.3 HD46AE244 RMOD46AE244FV4C_002 (Series A) ECM2.3 HD44AR131 RMOD44AR131FV4C_003 (Series A) ECM2.3 HD44AR132 RMOD44AR132FV4C_005 (Series A) ECM2.3 HD44AR133 RMOD44AR133FV4C_006 (Series A) ECM2.3 HD46AR244 RMOD46AR244FV4C_002 (Series B) ECM5.0 HD44AR120 HK44ER120FV4C_003 (Series B) ECM5.0 HD44AR121 HK44ER121FV4C_005 (Series B) ECM5.0 HD44AR122 HK44ER122FV4C_006 (Series B) ECM5.0 HD46AR223 HK46ER223
A13029 Fig. 7 − Easy Select Board
1/4" 10 11 12 1 2 3 4 5 6 7 8 9
F. Heat Pump Heating Mode — Single Speed or Two−Speed adjust airflow as required. Below 10 F., the W1 control output High will automatically energize on a call for heat. The ECM2.3/5.0Thermostat closes R to Y/Y2 and R to G. A circuit R to Y1 is power connections are made at the transformer primary terminals.required for two−speed high operation. The unit delivers airflow The transformer secondary connections are made at SEC1 andselected by AC/HP SIZE selection and CFM ADJUST selection. SEC2 connectors.Selected delay profile is active in this mode. EASY SELECT CONFIGURATION TAPS G. Heat Pump Heating Mode — 2−Speed Low The Easy Select taps are used by installer to configure system. TheThermostat closes R to G and R to Y1. Unit delivers two−speed ECM2.3/5.0 uses selected taps to modify its operation to alow airflow for AC/HP SIZE and CFM ADJUST selected. Selected pre−programmed table of airflows. Airflows are based on systemdelay profile is active in this mode. size and mode of operation and those airflows are modified in H. Non−Staged Auxiliary with Heat Pump Heating Mode response to other inputs such as the need for de−humidification. (See Fig. 7.)Thermostat should already have closed R to G, R to Y2 for heatpump heating operation. With J2 jumper in place, energizing either The FV4 Fan Coils must be configured to operate properly withW1 or W2 will produce the W2 airflow. This is the greater of heat system components with which it is installed. To successfullypump heating and auxiliary heat airflow plus an additional 15 configure a basic system (see information printed on circuit boardpercent. The elected delay profile is not active in this mode. located next to select pins), move the six select wires to pins which match components used, along with homeowner preferences. I. Staged Auxiliary Heat with Heat Pump Heating Mode A. Auxiliary Heat RangeThe auxiliary heat can be staged by removing the J2 jumper thatties W1 and W2 terminals together. Staging can be done by using The installer must select the auxiliary heat airflow approved foroutdoor thermostats or by using the Intelligent Heat Staging option application with kW size heater installed. Each select pin is markedwhere the indoor control can be configured for three−stage electric with a range of heaters for which airflow (also marked) isheat. The unit will automatically adjust airflow when the different approved. For increased comfort select the narrowest kW rangestages of heat are energized. The airflow delivered will depend on matching the heater size, for example, 0−10 for a 10−kW heater.the heat pump size selected and electric heat size selected. The This airflow must be greater than the minimum CFM for electricgreater of the two airflows will be delivered. The selected delay heater application with the size system installed for safe andprofile is not active in this mode. continuous operation. Note that airflow marked is the airflow which will be supplied in emergency heat mode and heating mode J. Electric Heat without Heat Pump on air conditioners when electric heat is primary heating source. ToThermostat closes R to W and thermostat should be set up to ensure safe heater operation in heat−pump heating mode, whenenergize G with W. This is due to the Super Comfort Heat electric heaters are energized, the ECM2.3/5.0 will run the higherprogramming in the motor. Energizing W without G will result in of heat pump airflow and electric heater airflow. The factory25% lower airflow delivery. The selected delay profile is not active default selection is largest heater range approved. (See Fig. 7.)in this mode. B. AC/HP Size K. Super Comfort Heat Mode The factory default setting for air conditioner or heat pump size isThis is a special heating mode only available on FV4 fan coils largest unit meant for application with model of fan coil purchased.combined with a Thermidistat Control or Comfort Zone II−B. The installer needs to select air conditioner or heat pump size toWhen this option is selected, the indoor control will monitor the ensure that airflow delivered falls within proper range for size ofoutdoor temperature. The control will drop the G signal to the fan unit installed in all operational modes. (See Fig. 7.)coil when the outdoor temperature is between 10 and 40 F. This Unpack unit and move to final location. Remove carton taking caretriggers the motor to slow to approximately 213 CFM per ton. The not to damage unit. Inspect equipment for damage prior toheaters will stage as needed during this mode and the motor will
9installation. File claim with shipping company if shipment is These units deliver airflow depending on the system size selectionsdamaged or incomplete. and operating mode. The thermostat energizes a combination ofLocate unit rating plate which contains proper installation terminals on the Easy Select Board which tells the motor whatinformation. Check rating plate to be sure unit matches job CFM to deliver. The following are typical operating modes and thespecifications. terminals that should be energized on the Easy Select Board. C. System Type NOTE: The DH terminal on the Easy Select Board is forThe type of system must be selected. dehumidification. It is de−energized on a call for dehumidification. 1. AC—air conditioner (approx. 350 CFM/ton) I. Variable Speed Motor Logic Sequence: 2. HP−COMFORT—provides lower airflow than air condi- The ECM motors in these fan coils are programmed to deliver a tioner selection (approximately 315 CFM/ton) in heating variety of airflows. The motor goes through: mode. In cooling mode supplies 350 CFM/ton. COOLING 3. HP−EFF—provides same airflow for heat pump heating The nominal cooling airflow for these fan coils is 350 CFM per and cooling modes (approximately 350 CFM/ton). ton. Selecting the HI adjust tap increases the airflow to 400 CFMThe factory setting is AC. (See Fig. 7.) per ton. The LO tap decreases airflow to 315 CFM per ton. The low adjustment is only active during normal cooling mode. D. AC/HP CFM Adjust Removing the signal from the DH terminal reduces the airflow toSelect low, nominal, or high airflow. The factory selection is NOM. 80 percent of cooling airflow. Removing the G signal forThe adjust selections HI/LO will regulate airflow supplied for Superdehumidify reduces the airflow to 50 percent of cooling.cooling and heat pump heating modes only, +15 percent and −10 HEATINGpercent respectively. The adjust selection options are provided toadjust airflow supplied to meet individual installation needs for The base heat pump only heating airflow is determined by thesuch things as noise, comfort, and humidity removal. (See Fig. 7.) SYSTEM TYPE selection on the Easy Select Board. If HP−EFFICIENCY is selected, the airflow is the same as Cooling. E. ON/OFF Delay IF HP−COMFORT is selected, the airflow is 315 CFM per ton.NOTE: ON/OFF Delay is active only in cooling and heat pump The airflow will adjust up if necessary when auxiliary heating isonly heating modes. In auxiliary heat mode or emergency heat required. When both the Y/Y2 and W1 or W2 terminals aremode, the ON delay is 0 seconds and the OFF delay is fixed and energized, the motor will run the higher of the heat pump orcannot be overridden. electric heat airflows. During Super Comfort Heat mode, theSelect desired time delay profile. Four motor−operation delay indoor control removes the G signal from the board. This slows theprofiles are provided to customize and enhance system operation. motor to 75 percent of heat pump airflow. If the CFM adjust is set(See Fig. 7.) The selection options are: to LO, it will deliver 67.5 percent of heat pump airflow during 1. The standard 90−seconds off delay (factory setting 0/90). Super Comfort Heat mode. 2. No delay option used for servicing unit or when a thermo- TROUBLESHOOTING stat is utilized to perform delay functions (0/0). A. Troubleshooting Easy Select Board (FV4) 3. A 30−seconds on/90−seconds off delay profile used when it If Traces Are Overheated on Back of PCB: is desirable to allow system coils time to heat up/cool down Usually whenever there is a trace broken on PCB, it means either prior to airflow. This profile will minimize cold blow in there has been a high−voltage short or high voltage has been heat pump operation and could enhance system efficiency applied to low−voltage circuit. This can be prevented by making (30/90). sure PCB is wired correctly before fan coil has power applied to it. 4. ENH, enhanced selection provides a 30−seconds If PCB Fuse Keeps Blowing: on/150−seconds at 70 percent airflow and no off delay. When low−voltage fuse blows, it means transformer would have F. Continuous Fan blown if fuse had not been in circuit to protect it. The fuse usuallySelect desired continuous−fan profile LO, MED, or HI. Airflow are blows when there is a high current drawn on transformer, highprovided to customize and enhance the continuous fan functions. voltage applied to low−voltage circuit, or a direct secondary short.(See Fig. 7.) The possible selections are: When there is a high current drawn on transformer, it is most likely 1. LO—provides 50 percent of Y/Y2 Cool airflow. because transformer has been shorted or system is trying to draw 2. MED—provides 65 percent of Y/Y2 Cool airflow (71 per- more Vac than transformer rating allows. When fuse blows because cent on 006 model). of high voltage, the system has mixed high and low−voltage signals. 3. HI—provides 100 percent of Y/Y2 Cool airflow. 1. Check transformer and thermostat wiring. (See Fig. 7.) BeThe factory setting is LO. sure transformer is not shorting out because thermostatNOTE: If applied to two−speed unit, do not select continuous fan wires are miswired.as HI since low speed cooling will also run at HIGH airflow and 2. Check wiring of relays. (See Fig. 7.) Be sure low−voltageinsufficient dehumidification may result. and high−voltage wiring are connected to proper sequen- G. Easy Select Board Jumpers cers.J1 − This jumper must be pulled to activate dehumidification 3. Check VA draw on transformer. If VA draw is more thanmode. The jumper connects R to DH. With the jumper in, the DH VA rating of transformer, fuse will blow. If this is the case,terminal is always energized. With the jumper pulled, the DH replace transformer with one that has a higher VA rating.terminal is de−energized. A control such as the Thermidistat must B. Troubleshooting Common Problemsbe used to supply the 24−V signal when there is no call for Airflow Too Low:dehumidification, and turn off the 24−V when there is a call fordehumidfication. Y1 instead of Y/Y2 on single−speed air conditioner or heat pump application. Y1 input is only for two−speed applications. UsingJ2 − This jumper activates heat staging. The jumper connects the this terminal will deliver about 60 percent of full cooling airflow.W1 and W2 terminals together. If either is energized, W2 airflow isdelivered. With the jumper pulled, there are separate airflows for Wrong Easy Select Board selection. Selecting an outdoor unit orW1 and W2. electric heater smaller than actually installed will result in low airflow for the application. H. Airflow Delivery 10G not energized with call for cooling or heating. This triggersSuper Comfort Heat or SuperDehumidify mode which delivers 50percent of cooling airflow. ! CAUTIONJ1 jumper pulled with no thermidistat or dehumidistat installed. ELECTRICAL OPERATION HAZARDThe J1 jumper ties the DH terminal to R and is installed at the Failure to follow this caution may result in equipment damagefactory. When pulled, a Thermidistat or dehumidistat supplies a or improper operation.24−V signal to DH when there is no call for dehumidification(reverse logic). When there is no signal on DH, the motor reduces DO NOT remove or apply 5−pin plug on motor with powerairflow to 80 percent for better dehumidification. on. Arcing could occur, which can damage control moduleAirflow Too High:Wrong Easy Select Board selection. Fan coil is factory set for the Turn power back on and check the following:largest outdoor unit and largest electric heater. Select sizes that are 3. Check for 24Vac on SEC1 and SEC2. If no voltage isactually installed. present, check transformer.Continuous fan set too high for two−speed applications. Set to 4. Verify that approximately 230Vac is present at motor.MED or LO. 5. Verify low voltage control signals to motor according toMotor Will Not Stop: procedure below.Allow time for off delay to time out. In units built before serial Use following procedure to check low voltage signals:number 0101A, any W call will have a two−minute off delay The ECM motor in these fan coils receive low voltage signals fromindependent of delay selection. This is programmed into the motor the Easy Select Board through the wiring harness assembly. Theand cannot be overridden. combination of pins energized at the motor determines the speedIn units built after 0101A, the off delay on any W call is one the motor will run. The procedure below isolates the fan coil fromminute and cannot be overridden. all external devices such as a thermostat, condensing unit,Some power−stealing thermostats could bleed enough voltage to humidifier or electronic air cleaner. There is also a specificcause motor to run slowly when there is no heating or cooling call. troubleshooting example to demonstrate the process. Table 7Disconnect thermostat wires and wait two minutes to see if motor provides information needed to verify that the correct voltages arestops. If it stops, replace thermostat, or install resistor per present at the motor and the Easy Select Board.thermostat installation instructions. THERMOSTAT:Motor Will Not Start: 1. Remove all thermostat and accessory wires from Easy Se-See following section, "Troubleshooting ECM2.3/5.0 Motor and lect Board.Controls 2. On Easy Select Board, jumper screw terminals (1 at a time): C. Troubleshooting ECM2.3/5.0 Motor and Controls R−G, R−Y/Y2, R−Y1, R−W1, R−W2. If motor runs in all cases, check thermostat outputs. Thermostat wires may be ! CAUTION broken, or thermostat may be miswired, configured incor- rectly, or defective. If the motor does not run, or runs in ELECTRICAL OPERATIONS HAZARD some cases, but not others, continue this procedure to check wiring harness and circuit board. Failure to follow this caution may result in equipment WIRING HARNESS: damage or improper operation. 1. Remove 16−pin plug from motor. High voltage is always present at motor. Disconnect power to unit before removing or replacing connectors or servicing 2. Check for appropriate voltages on 16−pin connector with motor. Wait at least five minutes after disconnecting power screw terminals jumpered. (See Table 2.) before opening motor. 3. If signals check correctly, and motor does not run, inspect wiring harness for loose pins or damaged plastic that couldThe ECM/ICM motor used with this product contains two parts: cause poor connections.the control module and the motor winding section. Do not assumethe motor or module is defective if it will not start. Go through the 4. If connections are good, either control module or motor issteps described below before replacing control module, Easy Select defective.Board or entire motor. The control module is available as a 5. If proper signals are not present, check circuit board usingreplacement part. procedure below: D. If Motor Turns Slowly: 12−PIN PLUG (PL−1) ON EASY SELECT BOARD: 1. It is normal operation to run noticeably slower if G terminal 1. Completely disconnect wire harness from Easy Select is not energized in cooling or heat pump heating modes. Board. 2. Attach blower access panel. Motor may appear to run 2. Jumper the screw terminals one at a time; R−G, R−Y/Y2, slowly if access panel is removed. R−Y1, R−W1, R−W2 and check for appropriate voltages on E. If Motor Does Not Run: the Easy Select Board pins. If proper signals are not present, replace Easy Select Board. If proper signals are present atTurn power off, wait five minutes and check the following: the pins and not at 16−pin connector to the motor, the wir- 1. With power turned off, check 5−amp fuse on Easy Select ing harness is defective. Board. TROUBLESHOOTING EXAMPLE: 2. Check all plugs and receptacles for any deformation or cor- Motor is not running on a call for heat pump heating after rosion that could cause bad connections. Be sure plugs are jumpering the Easy Select Board screw terminals as described in fully seated. Thermostat section above. With all thermostat wires removed from Easy Select Board, place a jumper wire between R and Y/Y2 low−voltage screw terminals on the Easy Select Board.
11 1. Check Table 4 for pin number on 16−pin connector associ- the G terminal is energized (See Fig. 8). During Superdehumidify ated with the Y/Y2 signal. The correct pin is No. 14. The far mode, the G signal is not present and the auxiliary terminals are not right column of Table 4 shows that (−) 12Vdc should be energized. If the installation includes the use of this operating present between Pin No. 14 and Pin No. 1 (common) on the mode, do not use these terminals to control accessories. See 16−pin connector. Electronic Air Cleaner and Humidifier sections for further 2. Set meter to read DC voltage. Place meter leads between information. Pins No. 1 (common) and No. 14 and check for (−) 12Vdc. ELECTRONIC AIR CLEANER CONNECTIONS If signal is present, the problem is in the module or motor. If The AUX1 and AUX2 terminals are not always energized during signal is not present, the problem is either in wiring harness blower operation, as described above. When using an electronic air or Easy Select Board. cleaner with the FV4 fan coil, use Airflow Sensor. The airflowThese steps can be repeated for other modes of operation. sensor turns on electronic air cleaner when the fan coil blower isTo check Easy Select Board: operating. 1. Leave jumper wire in place between R and Y/Y2. HUMIDIFIER / HUMIDISTAT CONNECTIONS 2. Check Table 4 under Volt Meter on Easy Select Board Easy Select Board terminals HUM1 and HUM2 are provided for Plug column and row for Pin No. 14 on motor plug to see direct connection to the low−voltage control of a humidifier pin number on Easy Select Board that should have voltage. through a standard humidistat. These terminals are energized with The correct pin is No. 2. The column on far right will show 24Vac when G thermostat signal is present. Alternately, the 24−Vac voltage that should be present between Pin No. 2 and Pin signal may be sourced from the W and C terminal block No. 9 (common). connections when electric heaters are used as primary heating source. When using a Thermidistat Control, Zone Perfect Plus, 3. Place meter leads between Pins No. 2 and No. 9 on Easy or Comfort Zone II, the 24−Vac signal may be source directly from Select Board and check for (−) 12Vdc. the Thermidistat HUM terminal. 4. If voltage is present, the wiring harness is bad. If not, the G. FV4 Dehumidify Mode Easy Select Board is bad. NOTE: Humidistat must open on humidity rise.Verify Motor Winding Section: Latent capacities for systems using the FK4, FV4, and 40FK fanBefore proceeding with module replacement, check the following coils are better than average systems. If increased latent capacity isto ensure motor winding section is functional. With control module an application requirement, the field wiring terminal blockremoved and unplugged from winding section: provides connection terminals for use of a standard humidistat. The 1. The resistance between any two motor leads should be sim- FK4, FV4, and 40FK fan coils will detect the humidistat contacts ilar. opening on increasing humidity and reduce its airflow to 2. The resistance between any motor lead and the unpainted approximately 80 percent of nominal cooling mode airflow. This motor end plate should be greater than 100,000 ohms. reduction will increase the system latent capacity until the humidityIf motor winding fails one of these tests, it is defective and must be falls to a level which causes the humidistat to close its contacts.replaced. When the contacts close, airflow will return to 100 percent of the F. Accessories selected cooling airflow. To activate this mode, remove jumper J1 and wire in a standard humidistat. Carefully consult productAUXILIARY TERMINALS airflow data for cooling and dehumidification modes.The AUX and HUM terminals on the Easy Select Board are tieddirectly to the G terminal, and provide a 24−Vac signal whenever Table 4 – FV4 Motor Control Test Values (With 16−pin connector at motor unplugged) Terminals Volt Meter on 12pin Volt Meter on 16pin Harness Plug Voltage Jumpered Easy Select Board Plug + + R to W1 Pin 2 Pin 1 Pin 7 Pin 9 24Vac R to W2 Pin 13 Pin 1 Pin 4 Pin 9 24Vac R to Y1 Pin 6 Pin 1 Pin 3 Pin 9 ()12Vdc R to Y/Y2 Pin 14 Pin 1 Pin 2 Pin 9 ()12Vdc R to G (LO) Pin 15 Pin 1 Pin 3 Pin 9 0Vac R to G (MED) Pin 6 Pin 1 Pin 3 Pin 9 ()12Vdc R to G (HI) Pin 14 Pin 1 Pin 2 Pin 9 ()12Vdc
12 FE4 is the System Status LED, and it is labeled STATUS. The greenModel FE4A fan coil is designed to be installed with a LED labeled COMM is also located adjacent to Systemcommunicating user interface. The FE4A fan coil will provide Communications connector, below STATUS LED, and is used asairflow at a rate commanded by the User Interface. The nominal an indicator of system communications status. Status Codes will beairflow/ton rate is 350 CFM/ton. The User Interface will modify displayed on the STATUS LED using the following protocol:the commanded airflow under certain operating modes. Refer to 1. The number of short flashes indicates first digit of code.the User Interface literature for further system control details. This 2. The number of long flashes indicates second digit of code.fan coil will not respond to commands from a common thermostat 3. A short flash is 0.25 seconds on. A long flash is one secondexcept under certain emergency situations explained in this on.document. 4. The time between flashes is 0.25 seconds.ELECTRONICALLY COMPUTED MOTOR ECM 3.0 5. The time between last short flash and first long flash is 1An ECM 3.0 is fed high voltage AC power through the 5−pin second.connector. The AC power is then internally rectified to DC by a 6. The LED will be off for 2.5 seconds before repeating code.diode module. After rectification, DC signal is electronicallycommunicated and fed in sequential order to 3 stator windings. B. Fan Coil Control Start−Up and System CommunicationsThe frequency of these communication pulses determines motor Troubleshooting:speed. The rotor is permanently magnetized. On power up, green COMM LED will be turned off untilECM 3.0 CONTROL POWER successful system communications are established (this should happen within 10 seconds). Once communications with UserThe ECM 3.0 control power is supplied from R circuit through Interface are successful, COMM LED will be lit and held on. Atprinted circuit runs to motor control connector Plug 1, Pin 1, the same time, amber STATUS LED will be lit and heldthrough motor control harness to motor. The C side of low−voltage continuously on until a request for operating mode is received. Thecontrol power circuit is connected by printed circuit runs to motor STATUS LED will be on any time fan coil is in idle mode.connector Plug 1, Pin 2 then through motor control harness tomotor. A digital signal is sent from Plug 1, Pins 3 and 4 to If, at any time, communications are not successful for a periodcommunicate with the motor including all airflow requirements. exceeding two minutes, fan coil control will only allow emergency heating or cooling operation using a common thermostat, aLOW−VOLTAGE CIRCUIT FUSING AND REFERENCE non−communicating outdoor unit and the R, C, Y, O, W outdoorThe low−voltage circuit is fused by a board−mounted 5−amp unit terminal strip connections and will display Status Code 16,automotive type fuse placed in series with transformer SEC2 and R System Communication Fault, on amber STATUS LED. Nocircuit. The C circuit of transformer is referenced to chassis ground further fan coil troubleshooting information will be available atthrough a printed circuit run at SEC1 connected to metal standoff. User Interface until communications are re−established.NOTE: The PCB must be mounted with two screws and motor If COMM LED does not light within proper time period and statusground lead secured to blower housing or erratic motor operation code is not displayed:can result. 1. Check system transformer high and low voltage to be sureTRANSFORMER, MOTOR, AND ELECTRIC HEATER the system is powered.POWER CONNECTION 2. Check fuse on fan coil control to be sure it is not blown. IfTransformer high voltage supplied from electric heater package or fuse is open, check system wiring before replacing it to behigh voltage leads through 12−pin heater connector plug/recp2. sure a short does not cause a failure of replacement fuse.The ECM 3.0 power connections are made at the transformer If COMM LED does not light within proper time period and statusprimary terminals. The transformer secondary connections are code is displayed:made at SEC1 and SEC2 connectors. Check system wiring to be sure User Interface is powered andTROUBLESHOOTING (FE4) connections are made A to A, B to B, etc. and wiring is notNOTE: Always check high and low voltage supply to the fan coil shorted. Mis−wiring or shorting of the ABCD communicationscomponents. Check the integrity of the plug receptacle connections wiring will not allow successful communications.and fan coil wiring harness prior to assuming a component failure. NOTE: Shorting or mis−wiring low voltage system wiring will A. LED Description: not cause damage to fan coil control or User Interface but mayLEDs built into fan coil control provide installer or service person cause low voltage fuse to open.information concerning operation and/or fault condition of the fan C. ECM Motor Troubleshootingcoil control and ECM motor. This information is also available at The ECM motor used in this product consists of two parts: thesystem User Interface in text with basic troubleshooting control module and the motor winding section. Do not assumeinstructions. Careful use of information displayed will reduce the motor or module is defective if it will not start. Use theneed for extensive manual troubleshooting. designed−in LED information aids and follow troubleshootingThe amber LED located at bottom center of control adjacent to steps described below before replacing motor control module ormotor harness plug is Motor Status LED, and it is labeled entire motor. Motor control module is available as a replacementMOTOR. A second amber LED, located in upper right center of part.control adjacent to System Communications connector (A,B,C,D),
13 2. Recheck airflow and system static pressure using User Inter- face service screens with access panel in place. NOTE: Blower motor faults will not cause a lockout of blower operation. Fan coil control will attempt to run the blower motor as long as User Interface maintains a demand for airflow. Fan coil control will not operate electric heaters while a fault condition exists. The fan coil control communicates with the motor at least once every five seconds, even when the motor is idle. If, during operation, the fan coil control does not communicate with the motor for more than 25 seconds, the motor will shut itself down and wait for communications to be reestablished. D. Using Motor LED in Troubleshooting The MOTOR LED is connected to the blower motor communication line and works with the fan coil control microprocessor and the STATUS LED to provide fan coil operation and troubleshooting information. When the motor is commanded to operate, the MOTOR LED will be turned on and will flash each time instructions are sent to the motor. When the motor is commanded to stop, the MOTOR LED will be turned off. If the MOTOR LED is lit, flashing and the motor is running or if the MOTOR LED is off and the motor is stopped, operation is normal and no motor fault exists. If the MOTOR LED is lit, flashing and the motor does not run, or if the MOTOR LED is off and the motor is running, check the STATUS LED for the Status Code. Refer to the troubleshooting instructions for the indicated Status Code in Section E, Fan Coil Troubleshooting. E. Fan Coil Troubleshooting Fan coil faults indicated by flashing codes on the amber system STATUS LED can be resolved using troubleshooting information provided below. Codes are listed in order of their priority, highest to lowest. Though multiple faults can exist at any time, only the highest priority code will be displayed on STATUS LED. Clearing A12231 the indicated fault when multiple faults exist will cause the next Fig. 11 − FE4A ECM 3.0 Motor highest priority Status Code to be flashed. All existing faults, as well as a fault history, can be viewed at User Interface.VERIFY MOTOR WINDING SECTION: STATUS CODE 45, CONTROL BOARD TEST FAULT: Fan coil control has failed internal start−up tests and must be ! WARNING replaced. No other service procedure will correct. STATUS CODE 37, HEATER OUTPUT SENSED ON ELECTRICAL SHOCK HAZARD WHEN NOT ENERGIZED: Failure to follow this warning could result in personal injury Fan coil control is provided with circuitry to detect presence of a or death or possible equipment damage. 24−Vac signal on Electric Heater stage 1 and stage 2 outputs. After disconnecting power from the ECM motor, wait at least If fan coil control detects a 24−Vac signal on either heater stage five minutes before removing the control section. Internal output and it is not supplying signal, Status Code 37 will be capacitors require time to discharge. Minor injury from displayed on STATUS LED. Fan coil control will turn off output electrical shock may result from early contact with live metal and command blower motor to supply an airflow determined to be parts. safe for current operation mode with electric heaters energized.Before proceeding to replace a motor control module: To find the fault: 1. Check motor winding section to be sure it is functional. 1. Stop all system operations at User Interface and check heat- 2. Remove motor control module section and unplug winding er stage 24−Vac outputs. plug. Motor shaft should turn freely, resistance between any 2. Disconnect electric heater at plug/receptacle 2 and check two motor leads should be similar and resistance between heater wiring for faults. See Status Code 36 for more in- any motor lead and unpainted motor end should exceed formation. 100,000 ohms. STATUS CODE 44, MOTOR COMMUNICATION FAULT: 3. Failing any of these tests, entire ECM motor must be re- The MOTOR LED is connected to the blower motor placed. communication line and works with the fan coil control 4. Passing all of the tests, motor control module alone can be microprocessor and STATUS LED to provide fan coil operation replaced. and troubleshooting information.MOTOR TURNS SLOWLY: When motor is commanded to operate, the MOTOR LED will be 1. Low static pressure loading of blower while access panel is turned on and will flash each time instructions are sent to the removed will cause blower to run slowly. Particularly at low motor. airflow requests. This is normal, do not assume a fault ex- ists.
14When the motor is commanded to stop, the MOTOR LED will be connector. If no resistor is found, system User Interface willturned off. The MOTOR LED will not flash to indicate prompt installer to verify that no heater is installed.communications when it is turned off. Verifying that this is correct will establish that fan coil is operatingFan coil control is constantly communicating with the motor, even without an electric heater accessory. Upon choosing negativewhen the motor and MOTOR LED are off. If motor does not option, installer will be prompted to select heater size installedacknowledge receipt of communications, the control will display from a list of valid heater sizes for fan coil and outdoor unit sizeStatus Code 44 on STATUS LED and continue to try to installed.communicate with the motor. If motor acknowledges If heater ID resistor value read is invalid, Status Code 26 will becommunication, status code will be cleared. displayed on STATUS LED.If MOTOR LED is lit and flashing and motor does not run: If heater installed is equipped with a resistor connected to Pins 5 1. Check the STATUS LED. If STATUS LED is indicating a and 8 of heater harness connector and Status Code 26 is displayed Status 44 code, check the motor wiring harness for proper on STATUS LED: connection to control and motor receptacles. 1. Check wiring harness connections to be sure connections 2. Check motor wiring harness to be sure all wiring complies are secure. with wiring diagram description, makes a complete circuit 2. If symptoms persist, disconnect wiring harness at fan coil from connector to connector and is not shorted. control heater header and check for a resistance value great- 3. Check 12−Vdc low−voltage supply to motor at Pins 1 (+) er than 5000 ohms. and 2 (−) of motor header connection to fan coil control. 3. Check for proper wiring of resistor assembly.If all checks are normal, fan coil control is good and control 4. Make sure heater size installed is an approved size for out-module on motor may need replacement. Check motor and Motor door unit and fan coil sizes installed.Control Module following the instructions in Section C. ECM NOTE: Fan coil control will not operate electric heater until thisMotor Troubleshooting. Status Code is resolved. If the heater size is set through the UserShorted or mis−wiring of the low voltage motor harness wiring Interface, the heater will be operated as a single stage heater. Ifwill not cause damage to fan coil control or to motor control staging is desired, the IDR value must be read in by the fan coilmodule. control.If the MOTOR LED is off, STATUS LED is indicating a Status Table 5 – FE4 Self−identifying Resistor ValuesCode 44 and motor is running: Heater Size Resistor OhmsDisconnect the motor harness at the fan coil control. If motor kW Nominalcontinues to run, fan coil control is good and control module on No heater Openmotor may need replacement 9 11kSTATUS CODE 25, INVALID MOTOR / MODEL SELEC- 15 18kTION: 20 24kOn initial start−up, fan coil control shall poll motor for its size data 24 33kand check fan coil size data stored in fan coil control memory. 30 39k 1. If motor size is incorrect for fan coil size or fan coil size data Hydronic Heat 270k is invalid, Status Code 25 will be displayed on STATUS LED. STATUS CODE 36, HEATER OUTPUT NOT SENSED 2. If model size data is missing (as is the case when a replace- WHEN ENERGIZED: ment fan coil control is installed), system User Interface will Fan coil control is provided with circuitry to detect presence of a prompt installer to enter correct model size from a list of 24−Vac signal on Electric Heater stage 1 and stage 2 outputs. valid sizes. If fan coil control energizes either heater stage and does not detect 3. If motor size is incorrect for model size, motor must be re- the 24−Vac signal on output, Status Code 36 will be displayed on placed with proper size motor. Fan coil control will not re- the STATUS LED Fan coil control will continue to energize heater spond to operation requests until this fault condition is output(s) and adjust blower operation to a safe airflow level for resolved. energized electric heat stage(s).STATUS CODE 27, INVALID OUTDOOR UNIT SIZE: To find the fault, check for 24Vac on heater stage outputs. Fan coilOn initial power−up, fan coil control will write into memory control or sensing circuit may be bad.outdoor unit size as provided by User Interface in a fully NOTE: It may be useful as an electric heater troubleshootingcommunicating system. procedure to disconnect the system communications to force Status 1. If outdoor unit size is invalid, Status Code 27 will be dis- Code 16 enabling of emergency heat mode. It is difficult to know played on STATUS LED. which heater output is energized or not energized in normal 2. User Interface will prompt the installer to choose size from a operation. When fan coil is operated in emergency heat mode using list of valid sizes for application with fan coil. electric heaters, both outputs are energized and de−energized 3. Check communications wiring to be sure User Interface has together. Terminal strip inputs to control can then be connected R established communications with outdoor unit or select to W to turn on both electric heat outputs. Heater output sensing proper size from valid size list provided at User Interface. circuits can then be checked to resolve Status Code 36 or 37 4. Check motor and motor control module following the in- problems. structions in Section C. ECM Motor Troubleshooting. STATUS CODE 41, BLOWER MOTOR FAULT:STATUS CODE 26, INVALID HEATER SIZE: If MOTOR LED is lit and flashing and motor does not run:On initial power−up, fan coil control will write into memory 1. Check STATUS LED. If STATUS LED is indicating Statuselectric heater size as read from heater if heater is provided with Code 41, motor control has detected that the motor will notIdentifier Resistor (IDR). Heater size must be valid for combination come up to speed within 30 seconds of being commandedof indoor and outdoor components installed. Fan coil control will to run or that the motor has been slowed to below 250 rpmread IDR value connected to Pins 5 and 8 of heater harness for more than 10 seconds after coming up to speed. Motor
15 wiring harness and fan coil control are operating properly, F. Emergency Heating and Cooling Modes do not replace. Fan coil control can provide emergency heating or cooling using a 2. Check to be sure that the blower wheel is not rubbing the common heat/cool thermostat in the event that there are no system housing. communications, fault is in User Interface and no replacement is 3. Check motor to be sure that the motor shaft is not seized immediately available. (motor control module must be removed and electronics To activate these modes, the thermostat and outdoor unit must be disconnected from windings to perform this check prop- wired as a common heating/cooling system to fan coil control erly). RYWC terminals. Fan coil control must be powered and displaying 4. Check motor windings section following instructions in Status Code 16, System Communication Fault. Section C. ECM Motor Troubleshooting. NOTE: These emergency modes do not provide the level ofIf all these checks are normal, the motor control module may need comfort and efficiency expected by the consumer and should onlyreplacement. be activated when User Interface cannot be replaced immediately.STATUS CODE 16, SYSTEM COMMUNICATION FAULT: FE4A FAN COIL SEQUENCE OF OPERATIONIf, at any time, system communications are not successful for a The FE4A fan coil is designed for installation with aperiod exceeding two minutes, the fan coil control will only allow communicating User Interface. This fan coil will not respond toemergency heating or cooling operation using a common commands provided by a common thermostat except under certainthermostat, a non−communicating outdoor unit, and the R, C, Y, emergency situations described in the Start Up andO,W outdoor unit terminal strip connections and will display Troubleshooting sub−section.Status Code 16 on the amber STATUS LED (see section E, The User Interface uses temperature; humidity and other dataEmergency Heating and Cooling Modes). No further fan coil supplied from indoor and outdoor system components to controltroubleshooting information will be available at the User Interface heating or cooling system for optimum comfort.until communications are reestablished. FE4A ADVANCED TROUBLESHOOTING:Check system wiring to be sure the User Interface is powered andconnections are made A to A, B to B, etc. and wiring is notshorted. Mis−wiring or shorting of the ABCD communications Statuswiring will not allow successful communications. Correcting LEDwiring faults will clear the code and reestablish communications.Shorting or mis−wiring the low voltage system wiring will notcause damage to fan coil control or to User Interface but may causethe low voltage fuse to open. CommunicationSTATUS CODE 46, BROWNOUT CONDITION: LEDIf the secondary voltage of the transformer falls below 15Vac for aperiod exceeding four seconds, Status Code 46 will be displayedon STATUS LED.If system includes a non−communicating outdoor air conditioneror heat pump, the User Interface will command the fan coil to turnoff Y output controlling compressor.When secondary voltage rises above 17Vac for more than fourseconds, the brownout condition is cleared and normal systemoperation will resume subject to any minimum compressor offdelay function which may be in effect. Brownout does not affectblower or electric heater operation.STATUS CODE 53, OUTDOOR AIR TEMPERATURE MotorSENSOR FAULT: LED
16 You can measure the signal with a DC voltmeter by remov- ing Plug 1 from the circuit board (HK38AE011) and con- necting the DC voltmeter across PL1−4 (+) and PL1−2 (−). The voltage should be near 0Vdc but it will fluctuate briefly several times per second. If you have an analog voltmeter, the needle briefly will go high several times per second. If you have a digital voltmeter with a bar graph, it will show a large change in magnitude on the bar graph several times per second. If you have a plain, digital voltmeter, it will show a brief fluctuation in voltage, and the magnitude may vary depending on the voltmeter used.
! WARNING ELECTRICAL SHOCK HAZARD A13031 Failure to follow this warning could result in personal injury Fig. 13 − FE4A ECM / Plug Wiring Diagram or death. Disconnect all power to the unit before servicing the fieldThe following troubleshooting techniques will assist in wires or removing the control package. The disconnect (whendetermining the correct component to replace when the Fan Coil used) on the access panel does not disconnect power to the lineBoard (HK38AE011) presents a Fault Code 44 or 41: side of the disconnect, but does allow safe service to all other 1. Disconnect power from the unit (240V). parts of the unit. 2. Disconnect the ABCD connector from the board. 3. Disconnect Plug 1 from the board (HK38AE011). (See Fig. The minimum maintenance requirements for this equipment are as 13.) follows: 4. Turn on power (240 volts). 1. Inspect and clean or replace air filter each month or as re- quired. 5. After reestablishing power, you should receive Fault Code 44, and the motor LED should be off. 2. Inspect cooling coil, drain pan, and condensate drain each cooling season for cleanliness. Clean as necessary. An in- 6. Place a jumper across the R and G terminals on the low spection port is provided on all A−coil delta plates. Remove voltage terminal block plastic plug to inspect. Replace plug after inspection. 7. Fault Code 44 should still be flashing. 3. Inspect blower motor and wheel for cleanliness each heating 8. The Motor LED should be flashing, indicating the board is and cooling season. Clean as necessary. able to transmit a signal to the motor. 4. Inspect electrical connections for tightness and controls for 9. If Motor LED is not flashing, check to ensure that 24V is proper operation each heating and cooling season. Service present across R and C on the low voltage terminal block as necessary. and that there is a good connection with the R and G jump- er. 10. If 24V is present and the jumper/connections are good, ! CAUTION 11. Replace the board. CUT HAZARDCheck Board Failure to follow this caution may result in personal injury. 12. If Fault Code 44 and the Motor LED are both flashing, place a DC voltmeter across terminals PL1-1 Red (+) to Sheet metal parts may have sharp edges or burrs. Use care and PL1-2 Green (-). (See Fig. 13.) wear appropriate protective clothing and gloves when handling parts. 13. Across terminal PL1−1 and PL1−2, a 12−Vdc should be present. If 12Vdc is not present, replace circuit board (HK38AE011). FILTER ASSEMBLY 14. If Fault Code 44 is flashing and the Motor LED is flashing, To clean or replace air filter, push plastic connectors toward center place a DC voltmeter across terminal PL1−3 (+) and PL1−2 of unit and remove filter access panel outward. Push filter up and (−). back into unit. Then slide filter out. 15. Across terminal PL1−3 (+) and PL1−2 (−), the DC volt Clean filter by using cold water and mild detergent. Rinse and meter should display 5Vdc. The voltage should be very allow filter to dry. No oiling or coating of filter is required. stable and should not fluctuate more than .02Vdc. If the New filters are available from your local distributor. Place filter in voltage fluctuates, get a different voltmeter before proceed- slot with cross−mesh binding up or facing cooling coil and replace ing to the following steps. filter access panel. 16. Reconnect Plug 1 to circuit board (HK38AE011) and con- COOLING COIL, DRAIN PAN, AND COND. DRAIN nect DC voltmeter across terminals PL1−3 Yellow (+) and The cooling coil is easily cleaned when it is dry. Inspect the coil PL1−2 Green (−). Does the voltage appear to fluctuate more and clean (if necessary) before each cooling season. To check or than in step 15? Typical voltmeters will show a fluctuation clean cooling coil, remove coil access panel. If coil is coated with of .2Vdc to 1Vdc. The amount of fluctuation is not import- dirt or lint, vacuum it with a soft brush attachment. ant. You could see even more fluctuation depending on the Be careful not to bend coil fins. If coil is coated with oil or grease, voltmeter used. clean it with a mild detergent and water solution. Rinse coil 17. Check the blower motor serial output signal. The blinking thoroughly with clear water. Be careful not to splash water on LED on the control board represents the serial output signal. insulation.
17 FFM and FMA B. Cooling Mode Thermostat energizes R to G, R to Y, and R to O (heat pump only). ! WARNING G energizes and completes indoor blower motor. Y energizes outdoor unit (O is energized for heat pump). When cooling call is satisfied, G is de*energized, there is a 90s blower off−delay. ELECTRICAL OPERATION HAZARD C. Heat Pump Heating Mode Failure to follow this warning could result in personal injury Thermostat energizes R to G and R to Y. G energizes and or death. completes circuit to indoor blower motor. When heating call is Before installation or servicing system, always turn off main satisfied, G is de*energized, there is a 90s blower off−delay. power to system. There may be more than one disconnect D. Heat Pump Heating with Auxiliary Electric Heat switch. Turn off accessory heater power if applicable. Lock out and tag switch with a suitable warning label. Thermostat energizes R to G, R to Y, and R to W1. G energizes and completes circuit to indoor blower motor. W1 energizes electric heat relay(s) which completes circuit to heater element(s). WhenFAN MOTOR W1 is de*energized, electric heat relay(s) open, turning off heaterThe FFMANP(018,024,030,036) and FMA4P motor is elements. When G is de*energized there is a 90s blowerthree−speed PSC direct drive. High−speed lead is black, off−delay.medium−speed lead is red, low−speed lead is blue, and common E. Electric Heat or Emergency Heat Modelead is purple. The FFMANP(019,025,031,037) and FMA4X Thermostat closes R to W1. W1 energizes electric heat relay(s)motor is a five speed ECM direct drive. The cooling speed tap is which completes circuit to heater element(s). Blower motor isselected by connecting the green wire to the desired motor tap energized through normally closed contacts on fan relay. When W1number indicated on the motor plug. For the electric heat fan speed is de*energized, electric heat relay(s) opens, there is no blowerselection connect the white wire to the desired motor tap number off−delay. (units with ECM motor will have a blower off delayindicated on the motor plug. Be sure proper blower speed has been based on motor speed tap selection).selected.The blower motor in this unit has blower−off delays. The Table 6 – Speed Tap and Delay−Off Timeblower−off delay is 30−90 seconds and will keep the motor Delay−running after a heating or cooling call ends. Speed OffThe motor is turned on through two different routes. The first Tap Time 18 24 30 36occurs when thermostat calls for the fan in cooling, heat pump, orfan−only mode. A 24−Vac signal is sent to relay, causing relay to Tap 1 30 − − − −close its normally open contacts, turning fan on. Tap 2 90 Default − Default −The second occurs when there is a call for electric heat. A 24−Vac Tap 3 30 − − − −signal is sent to heater sequencer/relay, causing it to close, directing Tap 4 90 − Default − Default230V through the normally closed contact of fan relay, turning fan Tap 5 30 − − − −on. The fan remains on until sequencer/relay/PCB opens.If motor does run, test motor for an open winding or a windingshorted to motor case. If either is present, replace motor.TIME DELAYFFMANP(019,025,031,037) and FMA4X have time delay builtinto the motor logic. FFMANP(018,024,030,036) and FMA4Punits with date codes prior to 1715V have sequencers.FFMANP(018,024,030,036) and FMA4P units with date codes1715V or later have a time delay printed circuit board.The Time Delay Printed Circuit Board (PCB) s a logic controlledtime delay activated by low−voltage control signal (G) fromthermostat. The PCB includes a normally open relay which closesto energize the blower motor when the G terminal is energized.Then when the G terminal is de−energized the relay energizing theblower motor remains closed for 90−100 seconds before opening.NOTE: Aluminum coil models with PSC motor can be wired to Comments:different OFF time delay. See installation instructions for wiring 1. The THR and THC are connected to transformer output.diagram. 2. When the G has signal, the FAN will supply 24VAC power to control fan relay.NOTE: The following sequence of operation is based on units 3. Whe the G signal is gone, the FAN will stop 24 VAC outputinstalled with PSC motor and Time Delay Printed Circuit Board after 90 seconds.(PCB). For units with ECM motor, the off−delay is programmed 4. CN3, CN7 are dummy connection terminals.into the motor. Follow Table 6 below, ECM Motor Speed Taps & A150455Bthe corresponding blower off delay's for each speed tap. Fig. 14 − Time Delay PCB Schematic A. Continuous FanThermostat closes R to G. G energizes and completes circuit toindoor blower motor. When G is de*energized, there is a 90sblower off−delay.
18 A150463 Fig. 16 − 30 & 36 PCB
A150462 Fig. 15 − 18 & 24 PCB Fig. 17 − Time Delay Schematic
19ELECTRIC HEATER SERVICE The circuit between R and Y is also complete. This completedService can be completed with heater in place. Shut off power circuit causes contactor in outdoor unit to close which startsbefore servicing. compressor and outdoor fan. When thermostat is satisfied, its contacts open de−energizing contactor and blower relay. This A. Limit Switch stops compressor and outdoor fan motor. The indoor fan motorRefer to Electric Heater Kit Function and Troubleshooting section will stop after 90−100 seconds on the FFMANP(018,024,030,036)of this manual. and FMA4P, and 30 or 90 seconds on the B. Sequencer FFMANP(019,025,031,037) and FMA4X.Early EHK2 heater kits included sequencers instead of relays. HEATINGRefer to Electric Heater Kit Function and Troubleshooting section When thermostat calls for heating and FAN switch is set on AUTO,of this manual. the circuit between R and W is complete. The heater sequence SEQ C. Transformer is energized which closes contacts of relay. There will be a timeA 40−VA transformer supplies 24−V power for control circuit. delay. This completed circuit energizes all heating elements HTRCheck for 208/230V on primary side of transformer. If present, and blower motor. When thermostat is satisfied, its contacts opencheck for 24V on secondary side. de−energizing heat relay. This de−energizes the sequencer. AllNOTE: Transformer is fused. Do not short circuit. heaters should stop. The indoor fan motor will stop after 90−100 seconds on the FFMANP(018,024,030,036) and FMA4P, and 30 D. Fan Relay or 90 seconds on the FFMANP(019,025,031,037) and FMA4X.Later EHK2 heater kits included relays instead of sequencers. B. Heat PumpRelay coil is 24−V. Check for proper control voltage. Replace relay COOLINGif faulty. On a call for cooling, the thermostat makes circuits R−O, R−Y, andCLEANING OR REPLACING REFRIGERANT R−G. Circuit R−O energizes reversing valve, switching it toFLOW−CONTROL DEVICE cooling position. Circuit R−Y energizes contactor starting outdoor FFM AND FMA4P fan motor and compressor. Circuit R−G energizes indoor unitThe FFM and FMA4P piston can be removed and cleaned if blower relay starting indoor blower motor.believed to be plugged. This unit's piston is unique and When thermostat is satisfied, its contacts open de−energizingreplacements are available from RCD. contactor reversing valve and blower relay. This stops compressorThe filter drier should be located on the liquid line at the indoor and outdoor fan motor. The indoor fan motor will stop afterunit to prevent particulate from plugging the piston. 90−100 seconds on the FFMANP(018,024,030,036) and FMA4P, and 30 or 90 seconds on the FFMANP(019,025,031,037) and FFM AND FMA4X FMA4X.The FFM and FMA4X fan coils use an R−410A TXV. The TXV's HEATINGare preset at the factory and do not need adjustment for reliable On a call for heating, the thermostat makes circuits R−Y and R−G.operation. Reference the outdoor unit instructions to properly Circuit R−Y energizes contactor starting outdoor fan motor andcharge the unit to the correct subcooling. For optimal performance, compressor. Circuit R−G energizes indoor blower relay startingadjust the TXV so that 6º F of superheat is measured at the outdoor blower motor.unit's vapor service valve when the indoor return air is 80º F Should temperature continue to fall, R−W circuit is made throughDB/67º F WB and outdoor ambient is 82º F DB. To increase second−stage room thermostat bulb. Circuit R−W energizes asuperheat turn the TXV adjustment stem clockwise no more than sequencer bringing on supplemental electric heat.one rotation at a time. After an adjustment is made, wait until thesuperheat temperature has been stable for 15 minutes before When thermostat is satisfied, its contacts open de−energizingmaking further adjustments. contactor and sequencer. All heaters should stop. The indoor fan motor will stop after 90−100 seconds on theSEQUENCE OF OPERATION FFMANP(018,024,030,036) and FMA4P, and 30 or 90 seconds onA. Condensing Unit the FFMANP(019,025,031,037) and FMA4X.COOLINGWhen thermostat calls for cooling, the circuit between R and G iscomplete and single−pole single−throw relay FR is energized. Thenormally open contacts close causing blower to operate.
20 *
A14213 Fig. 18 − FFMA and FMA4 (Sizes 18 & 24) Expanded View − Case
A150305Fig. 19 − FFMA and FMA4 (Sizes 18 & 24) Expanded View − Duct Components, Blower & Electrical Parts
21 A13137 Fig. 20 − FFMA and FMA4 (Sizes 18 & 24) Expanded View − Evaporator Parts & Drain Pan
A14214 Fig. 21 − FFMA and FMA4 (Sizes 30 & 36) Expanded View − Case
22 A150306Fig. 22 − FFMA and FMA4 (Sizes 30 & 36) Expanded View − Duct Components, Blower & Electrical Parts
A13140 Fig. 23 − FFMA and FMA4 (Sizes 30 & 36) Expanded View − Evaporator Parts & Drain Pan
23 ELECTRIC HEATER FUNCTION AND 2. Check for shorted elements to ground. TROUBLESHOOTING 3. Replace sequencer/relays. They may be stuck closed. E. Nuisance Trips FB4, FE4, FF1E, FH4, FV4, FX4, FZ and PF4 1. Check for low airflow due to dirty filters, blocked registers,This section describes KFC, and KFD series electric heaters in or undersized duct.exclusion of Smart Heat by examining the functional operation of 2. Check blower motor and wheel for proper operation. Ex-these heaters. cessive current draw of motor will cause internal overloadDESCRIPTION OF ELECTRIC HEATER COMPONENTS to trip. A. Limit Switch 3. The fan speed may be low.The limit switch is a temperature sensitive control whose function FFM and FMAis to prevent system from overheating in abnormal conditions. Thetemperature settings often vary from heater to heater due to This section describes EHK2 series electric heaters by examiningvariations in airflow patterns and element radiant heat conditions. functional operation of this heater.The devices are sized to remain on−line under heat pump Service can be completed with heater in place. Shut off powerconditions (115 air off coil) and minimum CFM, but trip to before servicing.prevent outlet air conditions above 200 F or excessive component DESCRIPTION OF ELECTRIC HEATER COMPONENTSor duct temperatures. A. Limit SwitchThe device itself consists of a bimetallic disc, which when The limit switch is a temperature sensitive control that's function isoverheated "snaps through" to open a normally closed to prevent system from overheating in abnormal conditions. Thehigh−voltage, high−current switch. When system temperatures cool temperature settings often vary from heater to heater due tosufficiently, the switch will automatically reset to its closed variations in airflow patterns and element radiant heat conditions.position. Normal failure mode for this switch is open. The devices are sized to remain on-line under heat pumpIf a limit switch has been determined to be defective, NEVER conditions (115 F air off coil) and minimum CFM, but trip toBYPASS THE LIMIT SWITCH. When replacing limit switch, prevent outlet air conditions above 200 F or excessive componentensure that it is replaced with a limit switch of identical opening or duct temperatures. The device itself consists of a bimetallic disc,temperature and closing differential. Limit switches are typically which when overheated "snaps through" to open a normally closedcolor coded to identify their range. high-voltage, high-current switch. When system temperatures cool B. KFC and KFD Electric Heat Relay sufficiently, the switch will automatically reset to its closedKFC and KFD electric heater packages have relays controlling the position. Normal failure mode for this switch is open.heater elements instead of sequencers. A small rectifier PCB is If a limit switch has been determined to be defective, NEVERmounted to each relay which converts the incoming 24−Vac BYPASS THE LIMIT SWITCH. When replacing limit switch,control signal to DC. ensure that it is replaced with a limit switch of identical openingIn addition to the rectifier circuit, the second and third stage relays temperature and closing differential. Limits switches are typicallycontain a time−on delay circuit of five seconds for second stage, color−coded to identify their range.and eight seconds for third stage. When the control signal is B. Sequencerremoved from the relays, all relays will open with no time−off Early production EHK2 heaters have sequences controlling thedelay. heater elements. The sequencer is essentially a thermally−activatedTROUBLESHOOTING KFC, AND KFD SERIES time-delay relay normally activated by low-voltage control signalsELECTRIC HEATERS from thermostat. The typical sequencer is a 1- or 2−pole normally open device which energizes within 30 to 70 seconds after A. Discolored Wire Insulation at Terminal application of control signal and de−energizes 60 to 90 secondsCheck quick−connect terminal at discoloration. Connection may be after control signal is removed.loose, creating a high resistance through connection point. In simplistic terms, the sequencers which we use are nothing more B. Fuse Failure than normally open limit switches which sit on top of a small 1. Check for shorted wire. Replace wire. Never try to fix wire resistive heater. When voltage is applied to this heater, a positive using electrical tape. temperature coefficient resistor (PTC), heat is supplied to a 2. Check shorted element. If element is shorted, replace heater. bimetallic disc which "snaps through" and closes switch. C. No Heat The time required for PTC to heat to a sufficient point controls ON 1. Check fuse for failure. If fuse has failed, refer to Fuse Fail- timing of device. The time required for disc to cool down when ure section. power is removed controls OFF time of device. The PTC can be varied to provide varied timing. Typically a short ON equates to a 2. Check for faulty transformer. Check output voltage of trans- long OFF. former secondary side R (red) and C (brown). Make sure output is between 18Vac and 30Vac. If output voltage is low Because this is a thermally−activated device, ambient conditions and input voltage tests normal, replace transformer. affect the ON/OFF cycle. Higher ambient temperature means shorter ON times and longer OFF times. 3. Check for miswired heater plug harness. Application of these devices is such that the first switch ON not 4. Check limit switch or sequencer failure. These switches only turns on first heater element, but also ensures that indoor fan should have failed in open position. If output voltage is zero is energized, because first ON is last OFF. This ensures fan remains volts, replace switch. ON until the last heater de-energizes. The Time Delay Printed 5. Check heater relay and PCB (KFC and KFD heaters only). Circuit Board (PCB) is a logic controlled time delay activated by Control voltage input to PCB should be 24Vac. Output to low−voltage control signal (G) from thermostat. The PCB includes relay should be 18−Vdc minimum. If input is present but no a normally open relay which closes to energize the blower motor output, replace PCB. If output is present, replace relay. when the G terminal is energized. Then when the G terminal is D. Heater Will Not Turn Off de−energized the relay energizing the blower motor remains closed 1. Check low−voltage wiring for miswire. for 90 − 100 seconds before opening.
24 C. Relays COOLING COIL, DRAIN PAN, AND CONDENSATELater production EHK2 heaters have relays controlling the heater DRAINelements instead of sequencers. A small rectifier PCB is mounted The cooling coil is easily cleaned when it is dry. Inspect the coilto each relay which converts the incoming 24−Vac control signal to and clean (if necessary) before each cooling season. To check orDC. clean cooling coil, remove coil access panel. If coil is coated withIn addition to the rectifier circuit, the second and third stage relays dirt or lint, vacuum it with a soft brush attachment.contain a time−on delay circuit of five seconds for second stage, Be careful not to bend coil fins. If coil is coated with oil or grease,and eight seconds for third stage. When the control signal is clean it with a mild detergent and water solution. Rinse coilremoved from the relays, all relays will open with no time−off thoroughly with clear water. Be careful not to splash water ondelay. insulation. CARE AND MAINTENANCE Inspect drain pan and condensate drain at the same time cooling FB4, FE4, FH4, FV4, FX4, FZ4 and PF4 coil is checked. Clean drain pan and condensate drain by removing any foreign matter from pan. Flush pan and drain tube with clearTo continue high performance, and minimize possible equipment water.failure, it is essential periodic maintenance be performed on this If drain tube is restricted, it can generally be cleared byequipment. high−pressure water. Cut plastic line and work outside condensateThe ability to properly perform maintenance on this equipment pan and away from coil to clean drain tube.requires certain mechanical skills and tools. The only consumerservice recommended or required is filter maintenance. (See FilterAssembly.) ! CAUTION ! WARNING UNIT DAMAGE HAZARD Failure to follow this caution may result in equipment damage. ELECTRICAL SHOCK HAZARD Do not use caustic household drain cleaners in the condensate Failure to follow this warning could result in personal injury pan or near the coil. Drain cleaners can quickly destroy a coil. or death. Disconnect all power to the unit before servicing the field BLOWER MOTOR AND WHEEL wires or removing the control package. The disconnect (when used) on the access panel does not disconnect power to the line Clean blower motor and wheel when cooling coil is cleaned. side of the disconnect, but does allow safe service to all other parts of the unit. ! WARNINGThe minimum maintenance requirements for this equipment are as ELECTRICAL SHOCK HAZARDfollows: Failure to follow this warning could result in personal injury 1. Inspect and clean or replace air filter each month or as re- or death. quired. Disconnect electrical power before removing any access 2. Inspect cooling coil, drain pan, and condensate drain each panels. Lock out and tag switch with a suitable warning label. cooling season for cleanliness. Clean as necessary. 3. Inspect blower motor and wheel for cleanliness each heating and cooling season. Clean as necessary. To clean blower motor or blower wheel: 4. Inspect electrical connections for tightness and controls for 1. Remove blower access panel. proper operation each heating and cooling season. Service 2. Remove motor leads from fan coil control. Note lead loca- as necessary. tion for ease of reassembly.
25 on blower−wheel vanes. Also, do not drop or bend wheel, to cooling coil. If coil is coated with dirt or lint, vacuum with a soft as balance will be affected. brush attachment.To reassemble blower: Be careful not to bend coil fins. If coil is coated with oil or grease, 1. Place blower wheel back into housing. Be sure to position clean it with a mild detergent and water solution. Rinse coil with correctly for proper location. clear water. 2. Reassemble cutoff plate to housing using identified holes Be careful not to splash water onto insulation. from disassembly procedure. Inspect drain pan and condensate drain at same time cooling coil is 3. Position motor and mount in same position as when blower checked. Clean drain pan and condensate drain by removing any housing was in unit. Secure motor mount on housing, using foreign matter from pan. Flush pan and drain tube with clear water. removed bolts. Make sure mount or motor is grounded to If drain tube is restricted, it can generally be cleared by blower housing. high−pressure water. Cut plastic line and work outside condensate 4. Locate blower wheel setscrew over flat on motor shaft. Ro- pan and away from coil to clear drain tube. tate wheel in housing. It should not rub housing and should NOTE: There MUST be a trap in condensate line. Trap must be at be centered in inlet opening. If not, loosen setscrew and least 3−in. deep, not higher than the bottom of unit condensate align as necessary. drain opening, and pitched downward to an open drain or sump. 5. Attach green wire to blower housing with screw. 6. (If applicable). Secure motor capacitor under strap and tighten strap screw. ! CAUTION 7. Slide blower assembly to blower deck. Be sure (once UNIT DAMAGE HAZARD blower is within the unit casing) to force blower assembly Failure to follow this caution may result in equipment damage. toward control box while sliding assembly into unit to en- sure that blower assembly engages deck properly. Do not use caustic household drain cleaners in the condensate pan or near the coil. Drain cleaners can quickly destroy a coil. 8. Fasten blower assembly to deck with screws previously re- moved. 9. Reconnect electrical leads to fan coil control. C. Blower Motor and Wheel 10. Reconnect electrical power to unit and test fan for proper Clean blower motor and wheel when cooling coil is cleaned. rotation. To clean or service wheel or motor, proceed as follows: FF1E, FFMA, FMA 1. Pull unit disconnect (when used) and remove blower accessThe minimum maintenance requirements for this equipment are as panel.follows: 2. Disconnect motor electrical leads from control box and ca- 1. Inspect and clean or replace air filter each month or as re- pacitor. Mark location of wires for reassembly. quired. 3. Remove the three bolts holding motor mount to blower 2. Inspect cooling coil, drain pan, and condensate drain each housing while supporting motor shell with hand. cooling season for cleanliness. Clean as necessary. 4. Pull motor inlet ring and blower wheel assembly out of 3. Inspect blower motor and wheel for cleanliness each heating blower housing. and cooling season. Clean as necessary. 5. With blower wheel, inlet ring, and motor mount still at- 4. Inspect electrical connections for tightness and controls for tached to motor, place motor on flat, horizontal surface, proper operation each heating and cooling season. Service shaft up. Mark position of wheel on motor shaft for reas- as necessary. sembly. 6. Loosen blower wheel setscrew and remove blower wheel ! CAUTION from motor shaft. NOTE: Further disassembly of motor and mount is not necessaryCUT HAZARD as adequate clearance is available to clean motor.Failure to follow this caution may result in personal injury. 7. Clean blower motor and wheel using a vacuum with a softSheet metal parts may have sharp edges or burrs. Use care and brush attachment. Remove grease with a mild solvent suchwear appropriate protective clothing and gloves when handling as hot water and detergent. Be careful not to disturb balanceparts. weights (clips) on blower wheel vanes. Do not drop or bend wheel as balance will be affected. To reassemble unit, proceed as follows:A. Air Filter 1. Place motor with mount attached on flat, horizontal surfaceThe air filter should be replaced as needed. with shaft up. 2. Set inlet ring on top of motor mount grommets. Center inlet ! CAUTION ring flush on all three grommets. 3. Slide blower wheel onto motor shaft with setscrew upward UNIT DAMAGE HAZARD and aligned with shaft flat portion. Vertically position wheel Failure to follow this caution may result in equipment damage. along shaft to position marked during disassembly. Never operate unit without a filter. NOTE: If previous shaft was not marked or if replacing previous motor, set blower wheel position by sliding blower wheel along motor shaft to 1−1/8−in. above rubber grommets. (See Fig.24.)B. Cooling Coil, Drain Pan, and Condensate Drain 4. Hold blower wheel in place and carefully tighten setscrew.The cooling coil is easily cleaned when it is dry. Inspect coil and 5. Position motor and blower wheel assembly to blower hous-clean (if necessary) before each cooling season. To check or clean ing as originally oriented.cooling coil, remove blower/heater access panel to gain full access
26 6. Secure motor mount to blower housing using bolts previ- 9. Replace blower access door and tighten all four screws. ously removed. 10. Reinsert disconnect pullout only after blower access door is 7. Attach green wire to blower housing with screw. secured. Test blower for proper operation. 8. Connect electrical and capacitor leads to original terminals.
GROMMET MOTOR A86006 Fig. 24 − Motor, Inlet Ring, and Blower Wheel Assembly
REFRIGERANT FLOW−CONTROL When heat pump switches to defrost mode, refrigerant flows through a completely open (not throttled) TXV. The bulb senses DEVICES the residual heat of outlet tube of coil that had been operating inThermostatic Expansion Valves (TXV) heating mode (about 85 F and 155 psig). This temporary,The FX4, FV4, FF1E, and FE4 Fan Coils are factory equipped not−throttled valve decreases indoor pressure drop, which in turnwith a hard shutoff (HSO) TXV. The hard shutoff TXV has no increases refrigerant flow rate, decreases overall defrost time, andbleed port and allows no bleed−through after system is shutdown. enhances defrost efficiency.The TXV is a bi−flow metering device that is used in condensing PROBLEMS AFFECTING TXVand heat pump systems to adjust to changing load conditions by A. Low Suction Pressuremaintaining a preset superheat temperature at outlet of evaporator 1. Restriction in TXVcoil. The volume of refrigerant metered through valve seat is 2. Low refrigerant chargedependent upon the following: 3. Low indoor load 1. Superheat temperature sensed by sensing bulb on suction tube at outlet of evaporator coil. As long as this bulb con- 4. Low evaporator airflow tains some liquid refrigerant, this temperature is converted B. High Suction Pressure into pressure pushing downward on the diaphragm, which 1. Overcharging opens the valve via push rods. 2. Sensing bulb not secure to vapor tube 2. The suction pressure at outlet of evaporator coil is trans- 3. High indoor load ferred via the external equalizer tube to underside of dia- 4. Large evaporator face area phragm.The bi−flow TXV is used on split system heat pumps. In cooling NOTE: When installing or removing TXV, wrap TXV with a wetmode, TXV operates the same as a standard TXV previously cloth. When reattaching TXV, make sure sensing bulb is in goodexplained. However, when system is switched to heating mode of thermal contact with suction tube.operation, refrigerant flow is reversed. 5. The needle valve on pin carrier is spring−loaded, which alsoThe bi−flow TXV has an additional internal check valve and exerts pressure on underside of diaphragm via push rods,tubing. These additions allow refrigerant to bypass TXV when which closes valve. Therefore, bulb pressure equals evapor-refrigerant flow is reversed with only a 1−psig to 2−psig pressure ator pressure at outlet of coil plus spring pressure. If loaddrop through device. increases, temperature increases at bulb, which increases pressure on topside of diaphragm, which pushes pin carrier 27 away from seal, opening valve and increasing flow of refri- with a 3/4−in. Chatleff nut. (See Fig. 25) The threads are coated gerant. The increased refrigerant flow causes increased leav- with Loctite Heavy Duty Anti−Seize which is a graphite/calcium ing evaporator pressure which is transferred via the equal- fluoride formulation, for applications that is free from copper, lead izer tube to underside of diaphragm, with which the pin and sulfur. This product is typically used in applications with an carrier spring pressure closes valve. The refrigerant flow is operating range of −20°F to +2400°F. When replacing a TXV it is effectively stabilized to load demand with negligible change recommended to reapply with the same thread sealer. in superheat. Extra care should be taken during brazing of copper equalizer onALUMINUM COIL UNIT TXV's the aluminum coils to prevent the braze material from splatteringThe distributor used on the all−aluminum coils is also made of on the aluminum. Also, route the copper equalizer so that it doesn'taluminum. The TXV connection to the distributor is accomplished touch the aluminum components.
Thermal Loctite Expansion Valve Thermal Expansion Valve
A14212 Fig. 25 − Aluminum Coil Unit TXV's
CAUTION TEFLON SEAL PISTON ! UNIT DAMAGE HAZARD Failure to follow this caution could result in equipment damage. Damage may occur to the scroll compressor if operated at a negative suction pressure during a system pumpdown. PISTON BRASS RETAINER HEX BODY BRASS HEX NUT 1. Pump down outdoor unit. Close service valves at outdoor unit. A93530 2. Recover remaining refrigerant from tubing and coil through Fig. 26 − Refrigerant Flow−Control Device gage port on vapor−tube service valve. Disconnect refriger- (For FB and FMA4P) ant (liquid) tube from piston body. (See Fig. 26.) 3. Avoid damaging seal ring or machined surfaces on piston,Piston Body Cleaning and Replacement bore, and retainer.
CAUTION 4. Using small wire with a hook on end of it, remove piston ! from body.
ENVIRONMENTAL HAZARD Failure to follow this caution may result in environmental ! CAUTION damage. UNIT DAMAGE HAZARD Do not vent refrigerant to atmosphere. Recover during system Failure to follow this caution could result in equipment repair or final unit disposal. damage. When cleaning the piston orifice, be careful not to scratch or enlarge the opening, as this will affect operation.
28 6. Replace seal ring on retainer. Use two wrenches to separate the 13/16" Chatleff nut from the 7. The threads are coated with Loctite Heavy Duty Anti−Seize. distributor body. The threads will contain Loctite anti−seize, do not It is recommended to reapply with the same thread sealer. remove this from the threads. 8. Reconnect refrigerant tube to piston body. Install the piston and reattach nut to finger tight plus 1/2 turn. 9. Pressurize tubing and coil, then leak check. The distributor used on the all−aluminum replacement coil is also made of aluminum. The distributor threads are coated with Loctite 10. Evacuate tubing and coil as necessary. Heavy Duty Anti−Seize which is a graphite/calcium fluoride
CAUTION formulation, for applications that is free from copper, lead and ! sulfur. This product is typically used in applications with an operating range of −20°F to +2400°F. (See Fig. 27.) When UNIT DAMAGE HAZARD replacing a TXV it is recommended to reapply with the same Failure to follow this caution could result in equipment thread sealer. Extra care should be taken during brazing of copper damage. equalizer on the aluminum coils to prevent the braze material from Use a backup wrench and do not over tighten, as deformation splattering on the aluminum. Also, route the copper equalizer so of the piston body will occur, causing the piston to lodge in a that it doesn't touch the aluminum components. partially open or closed position. WasherLIQUID TUBE STRAINERIn R−22 all units, the TXV and refrigerant flow−control device isprotected on the indoor coil by a wire mesh strainer. It is locatedinside the 3/8−in. liquid tube at field braze joint just outside unitcasing. Access to strainer is through field braze joint.
! CAUTION A14397 PERSONAL INJURY HAZARD Fig. 28 − Replacement Coil Distributor Adapter Failure to follow this caution may result in personal injury. If it is preferred to install the old TXV external to the cabinet due to Relieve pressure and recover all refrigerant before system repair or final unit disposal to avoid personal injury or death. access, follow the steps below: Use all service ports and open all flow−control devices, d. Field fabricate a piece of 3/8" OD copper tubing with including solenoid valves. flare and nut to attach to the TXV outlet. e. The piston in the replacement coil must be removed. Use two wrenches to separate the 13/16" Chatleff nut PRE−INSTALLATION from the distributor body. The threads will containExcept for coils only used with TXV fan coils, all−aluminum Loctite anti−seize, do not remove this from the threads.replacement coils are shipped with a piston body distributor, f. Remove the pistonpiston, and 90 degree inlet tube with piston retainer (including g. Reattach the inlet tube and tighten the nut finger tightTeflon seal). Coil sizes used only with TXV fan coils include the plus 1/2 turn.TXV as part of the replacement coil. h. Remove the old coil and install replacement coil perBefore installation of replacement coil, verify the piston is the instructions below. Reinstall the fitting door to the cabi-correct orifice size. The correct size should be on the outdoor unit net.rating plate. If in doubt, reuse the piston from the old indoor coil. 29 i. Field fabricate a 3/8" OD copper tubing with flare and Chatleff nut. The threads contain Loctite anti−seize that nut. can be reused. j. Braze this tubing and nut onto the liquid stub out. b. Tighten the nut finger tight plus 1/2 turn. k. Attach flare and nut to TXV outlet by tightening to c. The vapor header contains a small diameter stub tube finger tight plus 1/2 turn with two wrenches. for the equalizer line. l. Drill equalizer hole into suction line and braze the d. Cut the end of the stub tube. equalizer into the hole. e. Insert TXV equalizer and braze together. Caution must m. Attach the TXV bulb onto the suction line and insulate. be taken to avoid braze splatter from the aluminum n. Insulate the entire TXV body and outlet tubing to surfaces of the new coil. Caution must be taken to avoid prevent sweating. heating the factory joint of the stub tube to the vapor header.Old all−aluminum coils with TXV f. The vapor header contains an indentation for the TXVWhen replacing a previous all−aluminum coil that contains a TXV, bulb. Attach the bulb and insulate.the old TXV can be reused and mounted inside the cabinet. a. After removal of the distributor inlet tube and piston, the old TXV is attached to the distributor with 13/16"
Cond. Trough
Cond. Trough Delta Plate TXV
Strainer Rubber Plug Rubber Plug Drip Ring
Screws- Delta Plate To Pan (4 per unit) Vertical Condensate Pan
A13359 Fig. 29 − A−Coil Component Location
INSTALLATION− A−COIL UNITS ONLY e. Turn off electrical supply to outdoor unit.1. Recover system refrigerant. f. Front seat (close) vapor service valve. a. Attach gage/manifold set to service valves. g. Recover any remaining refrigerant. b. Start unit in cooling mode. NOTE: All condenser coils hold only a factory−supplied amount of refrigerant. Excess refrigerant, such as in long−line applications, c. Front seat (close) liquid line service valve. may cause compressor internal pressure relief valve to open d. Operate unit until vapor pressure reaches 5 psig (indicated by sudden rise in vapor pressure) before refrigerant is (35kPa), or until suction line LPS opens. 30recovered. If this occurs, turn off electrical supply to outdoor unit COIL SUPPORT COLUMNimmediately, front seat (close) vapor service valve, and recover any COIL TOP SEAL (PARTIALLY HIDDEN)remaining refrigerant. COIL TO CASING SCREW 2. Turn off electrical supply to indoor unit. DISTRIBUTOR 3. Disconnect condensate drain line. TUBE
! CAUTION EXPANSION DEVICE (PISTON SHOWN) PERSONAL INJURY HAZARD Failure to follow this caution may result in personal injury. Use of torch may cause oil to catch fire, resulting in personal injury or death. To remove components use tubing cutter only.
SCREW4. Disconnect liquid and vapor lines from indoor coil. Use a (PAN TO COIL) tubing cutter to cut the lines. LIQUID TUBE COIL BAFFLE (between5. Remove coil access panel. FIELD CONNECTION extension and pan) COLUMN6. Remove clip securing fitting panel to condensate drain pan and SCREW CONDENSATE PAN
3111. Remove coil from condensate pan. 17. Reconnect liquid and vapor refrigerant lines and condensate12. Attach new painted Top Seal to new coil using brass colored drain line. Install new filter drier(s). screws included with packaging. (See Figs. 30 and 31) NOTE: If a torch is used to unbraze the line set, protect the fitting13. Remove screw at bottom of coil extension and reuse to panel with a wet cloth or braze shield as necessary. attached Coil Baffle in same location. Long side of baffle 18. Evacuate line set and indoor coil to 500 microns, back seat toward pan. (See Figs. 30 and 31) (open) liquid and vapor service valves.14. Install new coil into condensate pan using two original screws 19. Turn on electrical supplies to indoor and outdoor units. and two support columns. 20. Check system refrigerant charge and operation. See Split−15. Install new coil pan assembly into unit and secure with one System Residential Air Conditioners and Heat Pump Service screw previously removed from unit casing. (See Fig.30.) Manuals for further information.16. Reinstall coil access panel. Coil Bracket Coil Mounting Screw Location
Coil Extension
Condensate Pan Coil-to-Pan Shield Screw
Coil Supports
Coil-to-Pan Screw
Condensate Pan Assembly
A14307 Fig. 31 − Slope Coil Component Location (1996 and Later)
R−410A refrigerant operates at 50−70 percent higher pressures than R−22. Be sure that servicing equipment and replacement components are designed to operate with R−410A refrigerant. R−410A refrigerant cylinders are rose colored. Recovery cylinder service pressure rating must be 400 psig, DOT 4BA400 or DOT BW400. R−410A refrigerant systems should be charged with liquid refrigerant. Use a commercial type metering device in the manifold hose when charging into suction line with compressor operating Manifold sets should be 700 psig high side and 180 psig low side with 550 psig low−side retard. Use hoses with 700 psig service pressure rating. Leak detectors should be designed to detect HFC refrigerant. R−410A refrigerant, as with other HFCs, is only compatible with POE oils. Vacuum pumps will not remove moisture from oil. Do not use liquid−line filter driers with rated working pressures less than 600 psig. Do not leave R−410A refrigerant suction line filter driers in line longer than 72 hours. Do not install a suction−line filter drier in liquid line. POE oils absorb moisture rapidly. Do not expose oil to atmosphere. POE oils may cause damage to certain plastics and roofing materials. Wrap all filter driers and service valves with wet cloth when brazing. A factory approved liquid−line filter drier is required on every unit. Never open system to atmosphere while it is under a vacuum. When system must be opened for service, recover refrigerant, evacuate then break vacuum with dry nitrogen and replace filter driers. Evacuate to 500 microns prior to recharging. Do not vent R−410A refrigerant into the atmosphere. Observe all warnings, cautions, and bold text.
Copyright 2018 CAC / BDP 7310 W. Morris St. Indianapolis, IN 46231 Edition Date: 07/18 Catalog No: SM-FANCOIL-07Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations. Replaces: SM-FANCOIL-06