Furnace w/ insect nest

[austinado16]

I'm upgrading the 1984 Duo-Therm forced air furnace with a 1990 version.  Same exact furnace with the exception of a redesigned sail switch.

Prior to installation, I discovered 2 paper wasp nests hanging from the exhaust tube, just above where the intake air fan draws in combustion air from outside the camper.  They were too big to successfully extract, and I knew that if there were nests there'd be more down inside.   So I took the blower sheetmetal apart and found this nice little mud hotel.


It actually wasn't affecting the rotation of the blower motor, or the plastic squirl-cage fan that runs the intake and exhaust air flow.  Still, not the kind of thing I want packed into my furnace.

IMO, if you find you have wasps, yellow jackets, or their paper nests, you probably want to remove the furnace and take it apart.  It's easy to do and won't take you that long.

[hoppy]

I had a simular problem with my 1978 Palomino that I bought back in 1990.
The furnace in that PU would leave a lot of soot deposit on the canvas at the exhaust vent. The flame in the furnace would burn with a yellow flame, and never be blue.

 I removed the furnace from the PU, and began to clean all the "innerd's"
Inside the venturi air supply tube, I found a mud dabber nest was restricting the air flow to the burner.

 After I cleaned it out of there, the furnace worked great for the next 10 years.