Hello all,

Our central air seems like it’s freezing up.

When we first turn it on, cold air comes out, and we see water coming out of the condensation line from the furnace.

After a while, the airflow slows, the air becomes less cold, no condensation comes out, and the cycles become longer and longer as it tries to maintain the temperature. Eventually the temperature in the house starts to rise. We sometimes see ice on the copper tubing leading from the compressor into the coil, on the outside of the furnace.

If we turn off the air conditioning for a while, things seem to return to normal for a while, and then the cycle begins again.

We have had technicians come out twice now and the problem still hasn’t gone away. We have already done the following:

-Changed the air filter
-Had the compressor and the coils cleaned
-Installed a programmable thermostat
-Had the unit checked for leaks (we had been told that our unit was low on coolant in previous years, but they were unable to find any leaks, and told us that the difference in pressure was likely because there was water in the lines with the coolant)

Most recently we were told by the technician that the reason why our unit was freezing up was because the air inside our house is warmer than the air in our underground garage (where the compressor is located). We’re in a townhouse complex and there’s not much we can do about the location of the compressor. We’ve lived here for several years, though, and this year is the first that we’ve had problems this severe.

Does anyone have any idea what else might be going wrong? We have pretty much run out of ideas of what else we can do, and the technicians do not seem to have any other suggestions as well. Before we call anyone else we’d like to get some opinions from others.

Thanks so much for your help.
Riona
The owner of the AC repairs company came by, checked out the unit, and said that the issue is low freon. Apparently the service tech who came out in previous visits did not put in the proper amount of freon because he did the calculations based on ambiant temperature from outside, but the AC unit is in our underground garage. There is a 10 degree difference between the temp outside and inside. The unit seems to be running fine so far and the air coming out is much colder.

Thanks for all your help!