We bought a newly built home during the Winter and were not told that the A/C unit had not been charged until after we'd been running it for several days 6 months later. The unit has not been running properly since. The installer came out 3 months later and said it was low on Freon and the filter was dirty. The following Summer, it again was blowing not so cool air again so we called them out once more (11 months after it was first charged but 17 months after we moved in). Again he said it was low on Freon and the filter was dirty. They offered to fill it up again, but wanted to charge us for it.

Is it likely that the unit was damaged in that few days of running it without it being charged up? If so, what is the likely damage and what needs to be done to fix it?

Overcharging tends to do more damage than undercharging. If undercharged too much then the compressor doesn't get lubercated.

The fix is to find a reputable contractor who is capable of finding the leak. It would be nice to know just how much refrigerant is looses in a given time.

Home AC units should not leak unless installed improperly. The only real source of leaking is the wire feedthroughs on the compressor. Corrosion on the fittings due to improper cleaning can contribute to leaks too. Sometimes the service fittings leak. I've seen AC units last 40 years without ever adding Freon.

Leak testing can be time consuming, There are electronic leak detectors which are extremely sensitive. There are UV dye based detectors for larger leaks and there is the leak down test used when the system is emply and filled with pressurized nitrogen.

In any event, there will be the time required to find the leak. Recovery of the freon. Repair. A leak down test (hurry up and wait). The longer you wait, the more sensitive the test. Charge and test performance which is basically the temperature difference acrooss the air across the coils in the furnace.

I agree, there has to be a leak, call the company that installed the system, make them fix it.

I agree, there has to be a leak, call the company that installed the system, make them fix it.

I contacted them last summer. They won't acknowledge that there is anything wrong with it. I'm trying to get ammunition (information) to use against them so I can get it fixed or replaced.

Well, a system should not leak, sometimes you have to get a little mean. You may have to call in another contractor, have them fix the leak, and send the original installer the bill.

Well, get it fixed by another contractor. Have them document the leak rate before and after the fix. Could be as simple as "Lost 10 microns of pressure in 1 hour before the repair and undectable after 1 hour after the repair when pressurized to 80 PSI of Nitrogen" The leak rate before, will cost you some labor, unfortunately.


Have stuff to support your original claim and try to recover the money paid in small claims court.