Air Conditioning - Payne A/C system blows hot air

Hello all, I apologize for asking what has probably been answered but I can't find a match.

When we turn on the a/c it comes on immediately. I watched the unit outside and the fan and compressor both turn on. Last year I had to replace the start/run capacitor because the fan would not run unless given assistance with a long stick and a quick spin. That whole summer the a/c responded pretty well without issue. Through the winter the heat worked as well. I should state that I believe this to be a air exchange heat pump system. Its a Payne from 2000, i believe, based on a sticker on the compressor that says the warranty begins in August of 2000. Inside the house is a very large unit with another coil system in it that has a large amount of copper tubing associated with it and a blower sitting above it. I took the covers off to expose this system and observed the blower operating. The "radiator system" was very hot as well as both the large copper pipe and the small copper pipe leading from outside in.

With the sides off the inside unit the system blew air the same temp as our basement where it was drawing in the air. When I put the sides back on it blows hot air the temp of the radiator and coils. This also occurred after removing and replacing the filter which sits below the radiator unit.

I feel this is probably a case of needing freon recharged but I am very unsure and hate to call for service without having some idea of whats going on. I don't want to second guess a tech but I also don't want to get "taken".

Thanks in advance for any help, and if needed I can upload pics.

If its a heat pump, it may be heating. How hot is the air coming out of the vents?

If its a heat pump, it may be heating. How hot is the air coming out of the vents?

Pretty hot. It'd be fine in the winter type of warmth coming out of the vents. The thermostat says "Cool" and reflects a temperature I generically set to 61 to test with.

While the unit is running feel the larger of the two pipes that go to the outdoor unit? Hot? Same as outdoor temp? Lukewarm? Cool? It's beginning to sound like you have a heat pump and it's in the heat mode for some reason.

While the unit is running feel the larger of the two pipes that go to the outdoor unit? Hot? Same as outdoor temp? Lukewarm? Cool? It's beginning to sound like you have a heat pump and it's in the heat mode for some reason.


Both pipes AT THE INSIDE UNIT are very hot. I will check tomorrow to see if this is the same at the outside unit with the compressor and fan.

Thanks for the points of check, I'll get back to you as soon as possible. By the way, I'm guessing the it is possible for the thermostat to be bad and causing this.

I doubt it's the thermostat, but anyhing is possible. It's more likely to be a problem in the reversing valve circuit or the valve tself. No need to check the pipes at the outdoor section.

Did you replace the thermostat since the last cooling season?