I've got a 5 ton Lennox system, about 10 years old.

The compressor is acting all wonky. It will run for about 10 minutes, then the compressor will turn off, but the fan keeps going. I've got the thermostat set to fan:auto. It's nearly 80 degrees out.

I've not gotten the compressor to come back on unless I turn off the system, then set it to heat. Wait the 5 minutes for it to come back on. Turn it off. Then set it back to cool.

At first I thought it was the cap. but the fact that the compressor turns on at all wouldn't make sense. I'm gonna have an HVAC tech come out, so I want to know what I'm talking about, haha.

Thanks!

 

Welcome to the forums.

What fan.... the one inside the house ?

If the compressor and the compressor fan shutoff at the SAME time..... then you may have a low refrigerant issue.

 

The fan on the outside unit stays on, but the compressor itself shuts off. We just had our frigerant topped off, because I thought it was that, too.

 

If the condenser fan stays running and the compressor shuts down..... it's probably overheating. It could be caused by a fan that isn't spinning fast enough or possibly a bad capacitor on the compressor.

I would have the capacitor checked or replaced first.

 

Why was the unit charged with refrigerant? Was the charge low? And was the leak found?
Your unit is a closed system. It also doesn’t consume refrigerant as it runs.
It could be overcharged now.