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turkeybucket 07-31-2012 02:57 PM

Evaporator Coil making strange sound
I have a 20 year old furnace and air conditioner, both Carrier. The noise sounds like water running through a pipe at high pressure/volume. Whenever the a/c unit turns on I get this noise after about two minutes of cooling (starting out soft, then getting louder) then it will stop immediately when the thermostat clicks off. This happens even with the furnace fan running continuously, ruling out the fan as the source. Is this possibly an indication of low freon in the system? I've never had it checked or had any added. TIA.

scottmcd9999 07-31-2012 03:47 PM

Sounds like refrigerant noise of some sort. Does the system seem to work okay? Is the outside unit running correctly?

IMO you'd be wise to have someone look into it. If it's an issue of coil cleaning or something of that nature, you could potentially save the compressor.

turkeybucket 07-31-2012 03:52 PM

thx for the reply! The outside unit seems fine, I do keep the coils clean. The only thing that may be different is that it seems to turn on, and stay on, more frequently. It's not really that hot out either, 84. It seems to be blowing plenty cold, but haven't measured it yet. I'll drop a thermometer in there right now and post again shortly. thx again.

turkeybucket 07-31-2012 04:05 PM

it's blowing at 55 degrees at one of the registers.

Dwillems 07-31-2012 04:34 PM

I had this noise in mine every time the system was low.

Edit: it was a carrier also. 3 ton r-22. Built in 89. I've since replaced the outdoor unit and the noise hadn't come back.

scottmcd9999 07-31-2012 05:54 PM

What's the indoor temp?

If everything seems to be running okay, then you're probably just experiencing a change in loads, which can cause odd noises at times. That said, anytime I hear liquid gurggling at the coil I think flooded coil, which often means charging issues or impending coil isues.
