So - It's not a "junk" Onan, just so happens your previous owner screwed it up. I would get the board replaced and fix that one or get another one. The ONan/Cummins are made for Rv's and plug and play. Not that you can't use another model, but there would be modifications to make it work in an RV. (Connections, Start, fuel delivery, exhaust, Bin mods to fit, mounting - just to name a few. )