Fisheyes from propane heater

[Whitesnake]

Just a guess but propane does give off a lot of moisture compared to other fuels.

I remember using a propane heater in another garage and writhing a few hours the was condensation everywhere so I have to believe this is true as well. I know they all put off some moisture but it seems like propane is the worst.

 

[crashtech]

The cleaner burning a fuel is, the more its exhaust will be comprised of water vapor. Propane only has 3 carbon atoms to 8 hydrogens so it's pretty clean, not as clean as natural gas, which is mostly methane, only 1 carbon to 4 hydrogens.

 

[hapcj7]

Yes, I used to live in New York state and did dry wall finishing in some of those freezing homes. That's when I bought this heater and it has always worked great.
You're right about letting it run out of fuel though. Fogged up the place in seconds and made you gag.

Yepp...100%!!!