Furnace Control Board Fuse Keeps Blowing

I am guessing that you are referring to the fuse on your control board is blowing and not the high voltage fuse blowing.

Furnace control board fuse keeps blowing.

Or just throw parts at it. Fuse on the circuit board blowing in your case you likely have a dead short somewhere in the wiring or a bad load that is going short to ground causing the fuse to blow. The coil in the contractor is 24v. The contractor may be hanging up or shorting.

It s possible that the problem could turn out to be with your electrical system rather than the furnace itself but your hvac system is the most likely suspect so it makes sense to start there. If the fuse keeps popping in your air conditioner you have a 24 volt short. But for those who ve recently encountered one common issue a furnace blowing its fuse before scheduling that tune up it may be due to one or more of the following reasons. Most of the time low voltage shorts are in the thermostat wires.

Regularly tripping the fuse can be a fire risk because it indicates an electrical problem. When your furnace keeps blowing a fuse you need to take action quickly. Here s how to diagnose a low voltage short. Assuming this is a fuse on the low voltage side coming off the 24 volt transformer it s possible the contactor in your condensing unit has shorted out causing it to blow the fuse.

Replacing the fuse or resetting the breaker can temporarily fix the problem but if the underlying issue is not fixed the fuse will just blow again. 4 points 3 years ago. Furthermore i would remove all the control wires from the board. If you haven t been diligent about maintaining your furnace all its parts will have been silently and steadily collecting debris and dust.

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 it is a low voltage fuse problem then you have a low voltage short somewhere. Amperage draw anything near the fuse rating would periodically blow a fuse. Im going to show you how to fix this problem with just a screwdriver and maybe 5 3 amp fuses and we will fix the 3 amp short im just making this video for my.

1 point 3 years ago.