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I'm sorry about your issues with your furnace. On a call for heat, does the small motor at the top of furnace start? Any LED flash codes?
Get a voltmeter, set to "volts AC" and check for 120 volts to the ignitor leads with a call for heat. If furnace is not lighting, we should be getting some kind of flash code.
How many flashes before a a pause?
That would be either an open high limit or one of the flame rollout switches.
The primary high limit will be on the back vertical plate about the size of a playing card with 2 wires attached. May look like this.
Flame rollout switches will be on either end of the burner area. Not sure if they use small disc shaped devices or fusible links.
Does the blower work OK, filter clean?
OK, well check those limits. One or more is open electrically.
First check and make sure one or more is open. You can turn power off, put the leads together on one switch at a time, and power back on. See if flash code goes away.
Flame rollout switch CLICK HERE
High limit CLICK HERE
The flame rollout switches have a small red button in the center that can be pushed in to reset
Try to reset flame rollout switches, then check again. The high limit you will need to turn power off, tape the metal ends of the leads together, then power back on.
Maybe the flame rollouts are bad. Try doing the same thing with both of them---tape leads together and try again.
If this doesn't work, we are missing a limit somewhere. Try taking several pictures of the burner area and upload here. To upload a pic, first save to your PC and upload using the small paperclip icon at top of the answer box.
Just use an unrolled paperclip to connect the two leads together. This is low voltage, so nothing to worry about. Just make sure they don't touch any metal parts.
I thought you already jumpered that one?
Yes, use the paperclip on that one, too.
Yes, I'd like to see several photos of inside the burner area. Make sure we're not missing a limit somewhere. You may want to also check down on the blower housing for one of those disc shaped devices. Sometimes they'll put a limit down there.
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