Furnace Cycling - SOLUTION w/ Pictures
EDIT: This turned out to be an air flow issue. The solution was quite simple. The furnace has three knockouts on the back when using flexible vent duct adapted to hard in-floor ducting. Crossroads has...
Forum Discussion
I recently tore my furnace apart (every piece) sorry to say but it's pretty much required to get to anything.. blower would start, It would spark but not ignite three times then shut down. I knew at that moment it was either orifice or bad valve. I cleaned it all up (Full of fine rust) and re-assembled and it fired right up, better than new. Based on your problem description I have the following thoughts.. It's an intimidating task but when you're cold.. you do what you need to do.
Blower is coming on and there is ignition.. I assume you can hear the fires burning.. I don't believe (I may be wrong) that it will light unless it's passed the sail switch stage (Which is located inside the blower/fan assembly on mine). So I'm saying sail switch is out.. High limit switch.. I'm not sure.. I'd say not likely.. My educated guess.. flame sensor? I believe the flame sensor is also the igniter. Clean it with some sand paper if it's not working correctly.. The other thing to check first would be that nothing has obstructed your in and outtakes.. Again, a semi-educated guess.. The other thing you can and should do is reseat the connection on the control board. OR.. Just wait for the service guy..
Blower is coming on and there is ignition.. I assume you can hear the fires burning.. I don't believe (I may be wrong) that it will light unless it's passed the sail switch stage (Which is located inside the blower/fan assembly on mine). So I'm saying sail switch is out.. High limit switch.. I'm not sure.. I'd say not likely.. My educated guess.. flame sensor? I believe the flame sensor is also the igniter. Clean it with some sand paper if it's not working correctly.. The other thing to check first would be that nothing has obstructed your in and outtakes.. Again, a semi-educated guess.. The other thing you can and should do is reseat the connection on the control board. OR.. Just wait for the service guy..
