My parents live in a country house and they've got a bunch of space heaters of various designs. Some of them are:
- Heating coil and a fan (hot air blower)
- Oil-filled battery
- Flat electric battery (no liquids inside)
- Infrared lamp
Only the infrared type doesn't make the air smell weird (or at least not as much as the other types). Others noticeably make the air smell like it's burnt or something. And they're all not new, so they've had enough time to work through whatever extra factory residue was on them originally.
I've spent some time enjoying the heat from campfires, fireplaces, hot evening breezes near large bodies of water, and a nervous couple minutes near a clearly faulty heater which was about to short out and give off a thick cloud of smoke. Those are all smells distinctly different from that.
Why are (properly functioning) heaters making the air smell weird? What's in that smell?
Best Answer
When air contacts a sufficiently hot object, dust in the air burns, and in some cases, particles from the hot object are also ejected similar to how dry ice sublimates. Dust can also gather on the heating filament when not in use, and burn off immediately when plugged in.
An infrared lamp with a sealed glass bulb contains the hottest point (the filament of the bulb) within a sealed glass enclosure, eliminating filament loss. Radiant heaters are also the least likely to stir currents of air over he heater.
For those two reasons, an infrared heater is least likely to produce a noticeable smell.