I have a Harman 52i since 2014. Really like it and it heats the house nicely. I have had burn pot issues since the beginning. They have warped and cracked near the igniter attachment slot in the burn pot. These were replaced under warranty. This year Harman sent a new burn pot 82 hole with the igniter now attached by two screws above the cleanout. I recently installed it after a complete cleaning of insert and also swept chimney. Burn pot does not ignite pellets and they spill into ash pan. Igniter in new and comes on verified by light on control panel and burn pot gets warm. Not sure what else I need to check. Any suggestions?