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ResemblesNorm
What sensor is this? Luxaire Furnace

I have a Luxaire natural gas furnace, model PANU-LD20N160A. It is 20 years old. It breaks down at least once every season, and I figure out which part has failed or needs to be cleaned. Today I had to temporarily bypass a device or sensor and I'd like to know what it is called. It is on the "ceiling" of the fire chamber, located midway between the ignitor at one end and the flame sensor at the other. Two wires run to spade terminals on either end of it, and it looks like a small plate of lead solder between the wires. I'm guessing if the fire chamber got too hot, the lead would melt, continuity would be lost, and the furnace would shut down. I will try cleaning all the connections first, but if I need to replace this part, what is it commonly called?

Sten
Re: What sensor is this? Luxaire Furnace

I was thinking maybe a roll out switch but it wouldn't be on the ceiling, it would be just outside past the manifold. This is a switch that opens and shuts the furnace down if the flame rolls out of the furnace, usually caused by a bad heat exchanger. Got any Pics???

ResemblesNorm
Re: What sensor is this? Luxaire Furnace

Thanks, Sten. It may serve a similar function, but it doesn't look like the rollout switches I can find on the web. I have now posted pictures with the original post.
I also determined that there is in fact no continuity (with the furnace off and cold) across this device, so I assume I will need to replace it.

Sten
Re: What sensor is this? Luxaire Furnace

More than likely it's some type of HL switch, if you put jumpers on the leads that go to the switch and the furnace runs but are not getting continuity when you go across the switch then it will have to be replaced. You seem pretty mech. inclined and should have no problem. Good Luck!!! :)

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