Furnace Control Board Fuse

Your furnace s control board has a separate fuse that protects it from getting too hot.

Furnace control board fuse. Is your air conditioner or furnace not turning on or p. I was blowing the 5 amp fuse on the control board for my forced air gas furnace. My furnace is a concord model cg90ub. Sometimes your furnace may seem like it has blown a fuse but it is actually suffering from loose wire connections.

Do you suspect that your furnace ac control board is bad. If the fuse didn t blow it meant the. I removed all the wires going to my thermostat and it would not blow the fuse when powered on. I replaced the original control board with a honeywell st9120u1011 universal control board about two years ago after the original one blew.

When a valve is unable to open and close properly it can sometimes heat up causing an electrical short that blows a fuse. The guy has a new condensing unit installed last year. If someone pokes around your furnace and isn t careful they may loosen wires from the furnace s wire frame causing them to short and blow a fuse on the control board. Diyers often try and handle things on their own.

Electric furnace problems can be frustrating especially when they come at the worst time. Here s how to diagnose a low voltage short. If the fuse blows when you have no low voltage wires hooked to the furnace then you have an internal problem like a bad limit gas valve connection or control board. If the fuse keeps popping in your air conditioner you have a 24 volt short.

I did a recent service call and the 5 amp fuse in the circuit board on the furnace was blown. Cartridge fuse flat blade dual element time delay class rk5 250vac 125vdc 200a 7 1 8 l 1 9 16 dia. Every troubleshooting tip i found said to disconnect the w heat relay and r 24v supply terminals from the thermostat and jumper them on the control board. Should i check amp draw on compressor and both fan motors.

If you have a gas furnace one of the valves may be failing. I turned off the input power and attached terminal r 24 vac power to thermostat and the fuse blew. Furnace or ac control board troubleshooting. It isn t the hsi inducer or blower motor as these are all high voltage parts not low voltage.

He just called and told me fuse is blown again. Electric furnace thermostat control wire.