[Alex lipowich]

Hi,

Thermostat seems to function, the sequence to start begins. "Induced Draft Blower" (small fan) comes on, but through the window, no flame starts.

In the past a failed Blower Door switch was repaired, and in the past, a squirell had dropped a rather huge nut-like object down the vent tube blocking the small fan, and I also found a pin loose in the ignitor plug to the main board that I had to repair.

This time it seems I have a clear 4 flash error code on the circuit board. This is "Ignition Failure". So, it seems to have cleared the pressure switches on the gas valve, but not gotten to flame recognition etc.... Since I don't see flame through the port/glass piece..... assume ignitor?

There is a sister furnace upstairs of same make and model. Is there a more reasonable way to determine if the ignitor is bad other than swapping a known good one in? Seems there ought to be a way to "Know" that this is the part I need to order.

Thanks in advance.

post script. Despite being gentle, removing the upstairs ignitor broke it. These must get fragile with age. Replacing with new solved problem. Lots of cross references for this part online, getting one with exact molex plug is not necessary. Though online ******** sources were cheapest, locally I had to drive a while to get one, and it didn't have plug, rather a pair of caps. No big deal. Unfortunately, this website did not carry the item at all.