Furnace Relay Switch Problem

Verify the furnace door is closed fully as an open door will cause the furnace not to work.

Furnace relay switch problem.

Furnaces require electricity to operate oil pumps thermostats internal electrodes relays and other electrical components. The reason for this is that the relay could become welded into the closed position and continues to allow power through to the heating elements and the fans. Switch it back on and see if this corrects the problem. You may have to check a few areas to eliminate this as a problem.

But another problem that occurs just as frequently from a faulty relay is that the heating elements and the blower fan will refuse to shut off. First make sure your furnace power is turned. Move the thermostat mode switch from cooling to off and move the fan switch from auto to on let the blower run for at least 30 minutes or until there s good airflow at the registers. Check the emergency switch usually located near the furnace room.

If this isn t the problem you can reset the power by switching the furnace off at the furnace power switch for about a minute. Many times wires are either loose or burnt behind the fan center relay. Turn off the furnace at. If the fan limit switch worked normally continue as follows.

Make sure that your furnace switch is on the furnace blower compartment door is on and secure. If it works for the next 12 hours you ve solved the problem. Then turn the ac back on to test it. That is definitely one possibility.

Turn off electrical power to the heating system reconnect the fan motor where you previously disconnected it turn on electrical power to the heating system call for heat. With the furnace on use a. Move the lever on. Set the building thermostat to call for heat.