What do you mean “will not work at high altitudes?” We had our stock B1 for two winter seasons. Much of that time was Colorado, and almost all of it was above 5000’. The blower motor failed last spring and we had it repaired in Denver. He did say it was sooted up pretty good, but he did not link that to any problem with the blower motor so I don’t think our use at altitude caused the blower motor to go.
My understanding is also that Espar now offers pumps/controllers that do better altitude compensation so you can probably get something to improve the performance even more.
If you want to sell it, knock yourself out, but I wouldn’t be quite so concerned about use at altitude as you say.
