All ActivityMost RecentMost LikesSolutionsFurnace doesn't light at altitudeThe Suburban furnace on a brand new Glacier Peak 5er won't light above 7,000 feet elevation. The furnace works fine up to about 6,000 feet. The trailer manufacturer says it is a "simple adjustment" but refuses to give the dealer "written" information. The furnace manufacturer states that their units are designed for use ONLY FOR USE BELOW 4,500 FEET. They say they put a sticker on the furnace and a note in the owners manual. Of course not one salesperson will ever tell a customer that. We have had two RV's in the past and the furnaces have always worked at altitudes up to 10,000 feet so maybe Suburban has "improved" their design to provide higher efficiency in the form of just don't use the furnace. So now neither the RV manufacturer or the furnace manufacturer is offering to help. Does anyone have a suggestion or know of a furnace that is really designed to work?