hollyb7841

I have 2 thermostats, 1 up and 1 downstairs. The upstairs, no problem, downstairs the commpressor does not run when I turn on the AC. To me it must be a faulty thermostat, since the upstairs thermostat turns the compressor on

hvactechfw

there are more components inline that just the thermostat there are a number of things that could keep it from turning on. First thing to check is breakers and voltage in and out of the contactor and that the contactor is pulling in with a call for cooling. Not saying it cant be the stat but most likely not.

kok328

as hvactechfw indicates there are many more components that would cause your condition. You'll need a volt/ohm meter to troubleshoot the problem. Without this tool, it would be next to impossible to fix.

paul52446m

I think you are saying that you have one condenser that is hooked to two blower coil unit. Is this right? If so you must have a relay in each indoor unit
to start the compressor. You would have to check the relay in that indoor unit
to see if it is working. Paul