I see two possible issues, both are easily addressed.
First: Electrical safety.. I use electric heat here, up to four 1500 watt heaters plus additional heat in the wet bays. (About 250 watts of light bulbs).
Some of the outlets if I plug a heater into 'em I get that old how insulation smell... Now I'v etaped over those, added heavy duty (15/20 amp) outlets fed with properly bent around a screw and tightened down 12ga wire But I worry about that hot wire smell.. It scares me and I don't scare easy.
The other issue is also mentioned above.. the wet bays.. Running the furnace vents hot air into the wet bays, thus helping water, remain liquid. (Wet bays have tanks and pipes that hold or carry water).
I added electric heat to those bays
I have a string of C-9 Christmas tree bulbs (these are the larger "Outdoor" lamps) 9 or 9.5 watts each, ending in a 100 watt rough service lamp. these are controlled by a Freeze Preventer outlet (it is a thermostatic outlet, turns on at 35 degrees)
I have seen the bay light up.
NOTE a 9 watt lamp works well in that string, lying right on the plastic floor of the enclosed bay. a 15 watt lamp,,, will melt plastic.
