O.T. Mr, Heater

Hey guys, any outdoorsmen out there that use a propane Mr. Heater at higher elevations? On their website they say don't use above 7000' feet. I am heading out west on a camping trip and would like to use mine at around 10k feet. Will it actually work and stay lit? Would it be dangerous other than the obvious precautions? Do I have to use a bigger propane tank?

I don't know anything about a Mr Heater, but I can do arithmetic. At an altitude of 10,000', the atmospheric pressure would have dropped from 14.7 PSI absolute to 10.11 PSI. This effectively increases the relative tank pressure by 32%. This pressure change will also reduce the amount of oxygen by air volume by the same percentage. This will affect the fuel mixer's ability to create stoichiometry.(correct fuel/oxygen mixture for combustion). Can you adjust the mixer? I suspect not enough with the factory 7,000 foot cap. It would probably require a jet change and even with that, the heat output would be reduced by about 30% from sea level. Please also note that the ability of atmospheric air to cool hot objects will also be reduced by 30%, which might cause overheating as well.

I've use mine right at 7,000 and other than not getting quite as hot it worked fine. I suspect if you get too high your biggest problem will be getting complete combustion, thereby producing copious quantities of CO.

I use mine at 6500 ft, and it works fine. In researching mine before purchase I was concerned about the mfrs elevation limitation and found some info on another forum that suggested moving thermocouple closer to flame, that information is INCORRECT. With low 02 flame stretches out past thermocouple.

I guess I never read the directions. We had our hunting camp at about 9000' and hunted about 10,000'. The heater worked fine. Tent camping got old so I bought a camper that had a furnace and could stay nice and warm all night.