Have a dc90 that at times burner does not ignite. Replaced igniter already,when I removed to clean one of the elements broke. Furnace seems to work okay when above 50 but below burner ignition comes on and other times not at all. Last week it never worked at all and Saturday outside temps went to 60 and furnace worked all weekend until tonight. Any help appreciated. I have read all posts here last week to try to fix this issue and one thing I have seen this is a great forum.