Anybody with Camco Olympian Heaters?

Thanks RJ, this makes sense. Camco probably discontinued them shortly after taking over, those 578xx models are still in the catalog but nowhere on the market. People complaining on propane appliances at high altitude don't understand basics of chemistry.

I don't know if contaminated catalyst may cause increased CO emissions. The article says that CO emissions increase when there is insufficient oxygen supply. I tend to believe them, their research looks very thorough. There is always some CO emission, though under normal burning conditions in catalytic heaters it's not heavy enough to worry about.