I have a Harman Advance pellet stove installed in 2004. Last winter there were pellets burning in the hopper. Changed ESP, all gaskets, cleaned slide and all components. Dealer does not know what caused the pellets to burn in the hopper. Will not ignite (igniter checks good). All blowers work. Bypassed pressure switch and still does not ignite. Looking for some help please. No error codes blinking.