If it’s too hot or too cold and your Heating, Ventilation and Air Conditioning system isn’t functioning.. follow these steps before calling out the repair person:
Begin your diagnosis of the HVAC system by verifying that it has power. Locate the service panel and ensure the circuit breaker has not tripped. The furnace and the air-conditioner each have their own dedicated circuit breaker or fuse. Turn the circuit breaker off for the unit that is malfunctioning. Wait about 10 seconds and switch it back on. If you have fuses instead of circuit breakers, switch the main power off. Remove and replace blown, burnt or broken fuses. Next check the thermostat for power. Some thermostats receive power via the electrical system, while others contain batteries. Remove and replace batteries for battery-powered thermostats if there is no power at the unit. Read MORE..
Do It And How 
I was wondering if anyone could help me? I have a 240 v 5 hp motor for my air compressor. I’ve cleaned centrifugal clutch and replaced start and run capacitor and motor still won’t start with any load. I can turn compressor pump by hand when compressor loaded so check valve on tank is good. Any suggestions?