The objective of Computer Controlled Recirculating Air Conditioning Unit, "TARC", is to introduce the student into the complex world of air conditioning systems, as well as studying and determining the optimal parameters for the operation of the unit in function of the environmental requirements (humidity, heat, temperature and cooling, etc.).



The Computer Controlled Recirculating Air Conditioning Unit, "TARC", has been designed to study both the changes in the air conditions and the refrigeration circuit. For that purpose, temperature sensors, pressure sensors and flow meters have been strategically located, allowing to study the refrigeration cycle and to quantify the capacity of the evaporation and condensation unit.

It can work with fresh air and recycled air.

The unit basically consists of a testing tunnel made of stainless steel, which has four windows (sight glasses). Inside there is an axial fan, two heating elements, one at the inlet of the evaporation unit of 2000 W and other at the outlet of 1000 W. There are also five hygrometers strategically located along the tunnel. These hygrometers consist of two temperature sensors (wet and dry bulb).




  1. Demonstration of the processes of air heating, cooling, humidification, de-humidification, recirculating and mixing.
  2. Efficiency determination of the preheating element.
  3. Preheating effect in an air conditioning installation.
  4. De-humidification process study.
  5. Mass balance in the evaporator.
  6. Energy balance in the evaporator.
  7. Re-heat effect.
  8. Experimental determination of the air specific heating capacity.
  9. Study of de-humidification in a recycling process.
  10. Sensors calibration.


Additional practical possibilities:

  1. Psychrometric chart.
  2. Usage of psychrometric chart.
  3. Determination of the airflow.
  4. Example of the air properties determination.
  5. Properties of the Refrigerant R134a.
  6. Enthalpy-Pressure diagram for the refrigerant R134a.
  7. Demonstration of recirculating and the adiabatic mixing of two air streams at different states.
  8. Obtaining of the steam generator efficiency curve.
  9. Energy balance in the steam generator.

Other possibilities to be done with this Unit:

  5. This unit can be used for doing applied research.
  7. Control of the TARC unit process through the control interface box without the computer.
  8. Visualization of all the sensors values used in the TARC unit process.