Atwood furnace problem..again

uhhhhh....he said its an attwood furnace.

I agree with dougrainer, replacing that many parts is unusual. If it is something you can do, I'd pull that puppy out and check it out fully. Pull your board and have it checked at a RV shop. There are devices for doing that. If there isn't any board, pull and clean all the connections. Something weird is happening in your heater. Check Suburban's website for repair manuals. They may have them in PDF format. I'd PM Chris Bryant and ask him about trouble shooting and repair manuals in PDF.

On Edit:

For spadoctor, I'm so very sorry, I put down Suburban and not Atwood. Please change procedure to check Atwood on line and check with Bryant about Atwood heaters.

I think the FIRST thing is a check out by a QUALIFIED RV Tech. Replacing all those parts in such a short time span is not correct. The motors last for years and the circuit boards rarely fail. The "burner" tube is also a rare failure, unless it was corroded. Do you still have the 2001 RV? If so, I would lean towards replacing the complete furnace(13 years old). Internal corrosion is what would cause the Motors to fail that quick and if the motors corroded, then the interior casing and such may have corrosion. Doug

Dirty sail switch
Bad time delay relay.
I would start by opening unit up and giving it a good blow job with some canned air. Look for the sail switch arm, extending into the blower housing. make sure you hit it good.

Maybe have a mobile tech come out.

Your sail switch is stuck.you could also have a bad thermastat