Step 1: With the electricity to the heating system turned off, first take out the thermostat casing or the thermostat itself to then reveal the cables.
Step 2: Remove the 2 cables from their terminals. If there are more than 2 cables then just pick red and white usually these are the standard colors for the electrical system and heating system, and for the cooling system you would choose the red and green coloured cables.
Step 3: Twine the 2 cables jointly.
Step 4: Switch the electricity on and keep an eye on the furnace. If the fan comes on and the furnace burner fires up then the thermostat is faulty.
Step 5: If you find that the burner does not fire up, check into the continuity of the cables from the thermostat to the furnace. If you’re testing the cooling system, then only the fan will turn on.
Step 6: Secure and fasten the terminal screws at all cable joinings.
View the following video for more ways you can test your thermostat.
