Why does a car air conditioner freeze up?

Answer 1

if it freezes up it has a restriction usually, expansion Valve ,the thing that is doing it ,but need to put some gages on it and see if the low side is going under vacuum since the low side in the suction side and it its vacuum ,but when the Gage's are hooked up on the high side and the low side ( suction & discharge ports) with the A/C on Max Fan on high the low side will stableize at about 29.9 inches of mercery or 30 to32 inchecs of vacume, if it starts going lower and the more rpm's added and the hight side climes drangersly higher that 250 275 300 the high side line can and will explode, so if this is happening you defenlety have a restriction, depending on what system r-12 or r-134-and this don't matter its the type of vehicle does it have a orifice tube or expansantion valve they both do the same thing ,and usaly this is what is wrong providing its full of freon and fan and all else is ok, this is most likely the place to look ok, good luck take care

Answer 2

If your drain hose is clogged up (the overflow hose running out the passenger side around the firewall on most vehicles) it will allow water to collect around the A/C unit where the fan blows. The freon or coolant feezes the small radiator like condensor in your heater box so when air is blown through it, it will cool the air before pumping it in the passenger compartment of the car. Due to the difference of temp the freon being compressed causes, it will make moisture condense in the unit. If this water touches the inside of the unit while the compressor is pumping the freon, the liquid will freeze on the metal parts. You will probably need to check the drain and free it up. Once you get rid of the condensation it will have nothing to freeze up on......

Answer 3

Car Ac Freezes Up

Answer 4

Because the evaporator coil gets too cold. The fan is supposed to blow sufficient air across the coil to keep it from getting too cold, but if the fan is not running fast enough the coils can go below freezing and get fouled with frost -- which further fouls the airflow so it gets worse. The solution is to shut the unit off until the frost melts. Home air conditioners can suffer the same fate.

Answer 5

There may be many reasons for not working:

1. Freeze up if as it doesn't work, check the fuse.
2. No cooling, no Freon or leakage in pipe. Condensor may be choked.
3. No or low pressure of air from pipes, the air intake system and vents needs cleaning.
4. If too much frosty, check the possible leaking of freon.

Answer 6

Ok it freezes over because the coils get too cold, you do NOT need to turn off ur A.C. just put it on vent, since it still runs thru the A.C. unit it will still be cool air but not like the A.C., wait a few min.s and then hit it at full blast, also if you have ur fan set on max and max A.C. then you turn the fan down on low quickly it will freeze over as well i hope this helped, good luck

Answer 7

If the system runs too long, the evaporator can get too cold and freeze. The A/C system is supposed to cycle on and off to prevent this from happening.

Answer 8

it absorbs the moisture from the air,when freezing up it usually means everything is working ok.Turn the thermostat up a bit to make it cycle on and off,that will rid the ice.

Answer 9

hi...i am a cert a/c tech..the a/c freezes up do to the condencer being dirty..you need to clean it...or you have a clog in the return vents..basicly the heat can not release and the system freezes..

Answer 10

First thing to do is have someone check coolant pressure and if it needs a shot of additional coolant. Its a low pressure problem