Hi again folks, so My Class A has "heated waste tanks" as labeled on the waste tank compartment door. I'm trying to figure out how this works. there's no on\off switch that I can find anywhere . ...
Probably will have to take a bright light and mirror and look for a 2-3" hole that was drilled through to the furnace floor duct. They usually do not put a grate over the hole thus making it difficult to locate. If both gray and black tanks are in the same bay there is only one hole located somewhere over the tanks in the floor above them, if separate bays are used both should have a hole for the heat.
The furnace needs to be operating for the heat to work in the bays as in the house.