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drtj2010-08-07 22:45:02 +0000 #1
My a/c is 2yrs old. Its not cooling like it should. I got to looking at it & I noticed my condenser is icing over. Anybody have an idea why its doing that.
tumbleweed2010-08-07 22:59:35 +0000 #2
is it a central unit if it is mine did that and the outside unit was dirty washed it out real good it was also low on freon ..hope this helps
IBBruin2010-08-07 23:25:38 +0000 #3
They will also freeze if they are low on freon.
Eight2010-08-07 23:34:07 +0000 #4
^^What they said.
badazzbrute2010-08-07 23:56:40 +0000 #5
Is your condenser or evaporator icing up? Check your evaporator for icing, more than likely, your evaporator is the problem. Most likely dirty. The suction line (bigger copper line of the two) should also be frozen. Clean your evaporator with a good evaporator cleaner, can generally find it at any hvac supply house. My guess is that if it is dirty enough to feed liquid back to, and through, the compressor, then you may have to hire a heating and air man to pull the coil and clean it outside with pressurized water. I am a heating and air man by trade, have been for over 10 years. Also, if the evaporator coil is this dirty, you will need to change your filter out more often, like once a month. Feeding liquid back to your compressor is a quick way to purchase a new one as liquid freon will lock up a compressor. If you or anyone else here ever needs information concerning this subject, just pm me.
CentralFloridaBrute2010-08-07 23:58:59 +0000 #6
probably has a leak somewhere in the lines, If the pressure goes below55-60area on a set of gauges itll ice up, like they said^ check your filter..if its dirty itll make your pressures different, if you can lean under and see the coil and it looks clean, your low on freon, is this a R-22 system or 410?
tacoma_20022010-08-08 00:28:15 +0000 #7

Remove your fan assembly (top of the A/C unit). Go down to the local parts house and get a gallon of "Aluma-Brite" acid. Dilute with water as described on the bottle and spray your "condesor coil" with the acid. Let it soak for about 30 seconds and wash it, from the inside out, with the garden hose.

Repeat as nessessary.

The acid isn't strong enough to eat away at the condensor coil when diluted (in its natural state its a killer aluminum cleaner for your atv!!!) so you'll be good to soak it down pretty good. I wouldn't take any sort of pressure washer to it for the fear of mashing the condensor fins down.

If your low on freon you'll sometimes experience this as well.

A simple pressure check on the low pressure side will tell if you need any freon or not....given you have a set of gauges. Problem is that when buying R-22, R-12 etc.. you have to have a HVAC/Refridgerant license.
phreebsd2010-08-08 00:15:49 +0000 #8
why does low coolant cause it to freeze up?

everyone seems to be in agreement that low coolant will cause it to freeze up.

(not doubting anyone, just wanting to learn. I think i mostly understand how an air conditioner cools the air.)
drtj2010-08-08 00:01:32 +0000 #9
From the sound of it my evaporator coil is dirty. I live in an older doublewide trailer. So the duct work is old. I am having to change my filter every 2-3 weeks. I am planning on running new duct work toward the end of the year.
badazzbrute2010-08-07 23:14:30 +0000 #10

Originally Posted by phreebsd

why does low coolant cause it to freeze up?

everyone seems to be in agreement that low coolant will cause it to freeze up.

(not doubting anyone, just wanting to learn. I think i mostly understand how an air conditioner cools the air.)

Freon temperature is based on its pressure. On an R-22 system if the suction pressure gets to 57.5 psi the temperature of the refrigerant is 32 degrees. The suction pressure is lower than the liquid or discharge pressure. The freon is metered down by an expansion valve/orifice/cap tubes just before the evaporator coil. This allows the freon temp to drop from about 108 degrees (in front of the metering device) to between 34 and 44 degrees (sent through the evaporator). In this case, if the evaporator coil (indoor coil) is too dirty, the expansion valve is going to squeeze off, lowering the pressure and temperature of the refrigerant going through the coil. This is amplified by the fact that if the evaporator coil is dirty, there is not enough warm air moving through the coil to properly heat the refrigerant up (superheat). Airflow has to be right, refrigerant charge has to be at minimum close, and refrigerant has to be properly metered. Airflow can be messed up by dirty coils, stopped up filters, and fan motors either not running, running slower than designed, or dirty fins in the squirell cage. I can go on and on, so I will stop now...



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