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.
The contractor may be hanging up or shorting.
Furthermore i would remove all the control wires from the board.
Regularly tripping the fuse can be a fire risk because it indicates an electrical problem.
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.
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.
The coil in the contractor is 24v.
If your furnace is blowing a fuse repeatedly leaving you with no power to the furnace your first step should be to call in an experienced hvac repair professional.
Here s how to diagnose a low voltage short.
If it is a low voltage fuse problem then you have a low voltage short somewhere.
If the fuse keeps popping in your air conditioner you have a 24 volt short.
Amperage draw anything near the fuse rating would periodically blow a fuse.
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.
1 point 3 years ago.
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.
It isn t the hsi inducer or blower motor as these are all high voltage parts not low voltage.
Or just throw parts at it.
If you haven t been diligent about maintaining your furnace all its parts will have been silently and steadily collecting debris and dust.
When your furnace keeps blowing a fuse you need to take action quickly.
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.
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.
4 points 3 years ago.