Here's a government test of a catalytic propane heater. It says they could only find 1 manufacturer of catalytics in 2003 so I guess they didn't look too hard. At that time I had at least 2 different ones, neither being the one they tested.
It says that in the presence of the catalyst, propane and O2 undergo a chemical reaction producing heat, CO2, and water. It's not a flame. It also says that when the O2 starts getting depleted, it creates CO instead of of CO2 and then things can get nasty. Keep the air coming in if you use one.
CATALYTIC TEST I have a camp trailer with a wall mount catalytic. It works great, but....if it's cold enough so we have to run it in the daytime, after a couple days everything is damp. We'll have water running down the windows. A couple years ago, we couldn't get our damp matches to strike to light the stove. We had to stick them in the heater to light them. Since then, I keep them in a waterproof can. I've never had much luck with the butane strikers. They never seem to strike more than once consecutively.
I'd like to return to the old propane furnace that used to be in the trailer but it's obsolete.
