Had a problem this morning, I think I figured out the cause but would like to hear other's opinions.
We woke to the smoke alarms going off at 4:30 this morning. There was faint smoke in the house, and a smell similar to burning plastic - but a little different. I did the rounds and determined the house was not on fire, then tried to locate the source of the problem.
Everything electrical checked out, felt for heat and tested for operation all outlets, switches, appliances. I had immediately shut down the furnace and the bathroom electric heated floor, so turned each of those back on, they operated normally and did not generate smoke. I went outside to check the wood boiler, and found the fire I set last night had gone out. This meant the propane furnace would have fired at about 4am when the thermostat kicks back up to morning temp. This would have been the first time the furnace fired on propane in 1-2 weeks.
So, I pulled the panels off the furnace and ran it through an ignition cycle. Everything was normal. Then I noticed that the blower motor run capacitor was leaking, had leaked enough fluid to spread across the bottom of the blower compartment. This is a 92% Goodman furnace, 4 years old, mounted in downdraft position. I think what may have happened is the fluid from the capacitor had leaked down into the heat exchanger, then when the propane fired for the first time in a while, it burned/smoked it off. I scraped up some of the fluid, sticky white pasty stuff, and burnt it off with a torch, we thought the smell was similar to what we smelled in the house.
Does this sound plausible? It's the only possible source/cause I can come up with. I'll be replacing the capacitor today, but just wanted to see if this was possible or anyone had seen this happen before.