"Stretch" wrote:

Is the filter inside the bottom of the furnace? The door switch on the
buttom of the furnace may be keeping it off. It prevents it from
sucking flue gas down the chimney when the blower compartment is open.

It's not in the bottom of the furnace, rather it's outside in a
separate compartment. There doesn't seem to be a switch or sensor for
the plain tin filter door.


It also may be a blown low voltage fuse.

I'll see if I can figure out where the fuse is -- thanks for the tip.

I never turn off the power to change the filter unless I have to open
the unit to do it.

I never used to, but after this fiasco I'm going to start!


Stretch