Anyone here know about HVAC? Need advise.

[Mark B]

Hey guys,
I own a condo. The condo is about 20 years old and the heating/ac system is the orginal. I have lived there for 3 years & every summer I sweat. Last summer I didnt even turn it on becuase I knew it wouldnt help much. The thermostat is brand new & I know it works. When I turn the system on on a hot day... It will run all day long & never get cold. If you put your hand in front of the vent, the air is definitly cooler than the air in the house... But not much.

My HVAC system consists of 2 units. I have the compressor outside & an air handler mounted ontop of my natural gas furnace. What should I do & who should I call? Can I get away with just replacing the compressor? Or do I have to replace everything? I dont want to spend a fortune. I will probably be selling the place in a couple years.

Thanks for reading & thanks for the help.

[Jeff_in_Atl]

There are 2 lines that carry refrigerant connected to the condensing unit outside. The small one is the high pressure and the large one is the low pressure. After about 30 minutes of running is the large line sweating water?

[Mark B]

I dont think I ever checked that. What will that tell me? If it has freon or not? I will have to wait till its a little warmer around here before I can turn the system on to check that.

[bru333]

You said it cools a little? If you are lucky it may just need to be recharged. No A/C system is perfectly sealed, some refrigerant will leak out over time. I'd call a service tech to hook some gauges up and see what it's doing. If you keep trying to use it with a low charge you may damage the compressor (the oil to lubricate the compressor circulates with the refrigerant).

[Jeff_in_Atl]

I dont think I ever checked that. What will that tell me? If it has freon or not? I will have to wait till its a little warmer around here before I can turn the system on to check that.

It will tell you if the condensing unit is working and how well it is working.

If it is not sweating it is not working. There are several reason why it is not working if not sweating. Like Bruce says if it is out of Freon it is out of lubricant too. If it is getting a little cold it sounds like it has some. Are the coils clear. When it's working right the fan will blow hot air out the top.

If it ices then the high pressure switch is bad or the evaporator orifice is clogged (usually caused by the compressor coming apart) or there isn't enough airflow over the coils to keep it from freezing over (bad air filter, no air filter and the coils have crap on them).

Someone has to do some diagnosis before a determination can be made. Whether that is you or a service tech.