What causes an a/c to freeze up.(ice on the pipes)

Question

What causes an a/c to freeze up.(ice on the pipes)

Answer 1

The moisture in the air freezes to the pipes and the vents so the air can't move.

set the a/c on low the first time you turn it on in a while, and let it run overnight, thenn you can crank it. That should keep it from freezing

Answer 2

very simple   low freon  have someone come out recharge the system and they should ck and clean the unit and you will have cold air again soon.   just did this at a friends house.

Answer 3

A problem with airflow,dirty filter ,dirty coil,blower running on wrong speed,blower not running at all,or metering device not feeding properly,or low on refrigerant charge.

Answer 4

Two main reasons, first air flow like dirty filters or dirty coil. The next is low on freon. The contactor can be stuck and the outside unit will not shut off. At the thermostat turn off the cooling and turn indoor fan to on this will help melt the ice. Once ice is melted look at the face side of the evap coil to see if it is dirty. Check the TD, measure the room temp and the vent blowing cold air, the difference should be around 18 degrees.80 room and vent 62 if it is a low TD say 12 degrees it is low on gas. If the TD is high like 25 degree TD you have a air flow problem