I purchased the heater February 2020, just now got around to installing it. Very bad instructions for install, thanks to YouTube I was able to get heater working and programmed.I have had several error codes but all of them happened to be my fault. Make sure you mount pump about 30 degrees up, you have primed the fuel line so pump doesn't have to pump empty. Make sure your battery or converter is good enough to operate the heater. Changed from Htz to C makes it easier to regulate. Once you do those things you shouldn't have any issues. Mine works great.It would have been nice if all items had been in box, but when you wait a year it's on me.I'm fixing to order another heater for the camper now that I know they work. This one is in a two car garage and it keeps it warm on low.