Originally Posted by Billshouse
If you raise the thermostat to start the heat it clicks on
Sounds like the 'former works, the 'stat is asking for heat and a relay is pulling in.
If you can the find the relay that is clicking measure the voltage across the closed
Less than 30 millivolts is good and more than 100 mVac is bad.
This is a $10 part depending on where you buy it.
Post whatever numbers and letters are on the relay case.