[howermj]

You don't have a heat strip in the basement air of the 2006 TM. Your front and rear roof air (if they were added) might have heat strips installed. Also, if you have Dometic A/Cs on the roof, the starter capacitor may have fried.

That said, if it is your basement air causing the burning smell, it could come from anywhere. Our basement air circulated a burning smell from a melted battery solenoid in the nearby engine electronics compartment. Smelled up the whole coach, and took forever to diagnose/repair. I would start with checking how your electrical system works...all the lights, chargers charging stuff they are supposed to charge, battery boost working. This is what clued us into the battery solenoid.