I switched from furnace to “heat strip.” Perhaps an hour later, I “switched back” to furnace. I went outdoors to double-check if it ignited. “Yes,” but the smell of propane was nauseating!! My eyes started burning. The old lady almost RAN indoors to turn off the furnace. Last winter, I survived the cold weather with “heat strip” and space heater. Space heater retrieved from storage trailer. I’ll “weather” the weather (lol). I’m thinking I’m extremely fortunate there wasn’t a fire that would have (very likely) destroyed my trailer home, KIA, and worldly possessions.