Thread: Romex through Furnace cabinet.

Furnace was installed with romex running in one end, through the furnace cabinet and enters the junction box/connection point on the other side. At best, I am thinking best practice would be to bring it in on the side of the junction box. But is this allowed?

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Not having the wiring diagram for that unit, I would have to say it is wrong based on common sense! The area that the NM cable is around might get pretty darn warm and I don't think it is rated for the heat that will be in that area. They really had to work hard to do it that way!

Is that flex vent pipe rated for use on this type of unit?

I don't think that running the cable like that is a problem.
I do see a problem with the unit sitting on the pan. If (when) the pan fills with water, the water will be inside the unit.

Hi Rick,

It is actually up past the flood rim of the pan, you just cant tell from the photo. The furnace across from this one had a reversed pitch flue, so I called them both out for review with special attention to the romex. I am leaning towards improper install. Otherwise, installers could take liberty and run the romex wherever they pleased in the cabinet. There are clearly some areas in that cabinet that installer wiring should stay away from.

Most manufacturers have provisions for the junction box to be moved to either side for this exact reason. All the wiring within the cabinet has been factory tested to function in that state. The installers romex was not present for those tests.

Are not all holes supposed to be sealed and the wires coming out of it have a garment too?

The only holes on this unit that need to be sealed are on the blower compartment, where the low voltage wires enter. The burner compartment does not need to be sealed as combustion air is drawn in through any openings. The romex, while not beautiful, is ok.