Moved into a 30 yr old house with a forced gas hot air heating system.
Saw something near the furnace wiring which I'm not familiar with.
Seems like they have a regular 4 inch square type gang box
mounted in very close proximity to the furnace with what looks
like a threaded rod/stud hanging downward from, with a round wheel on the
Is this a thermal safety shutoff ?
Who manufacturers them, and what are they "officially" called or termed ?
If so, how does it work; is it likely for the 110 V power feeding the
Would there be any possibility that if this is the purpose, they might have
wired into the chained together smoke detectors for an indication if it is
tripped ? Did they ever do this type of scheme with smoke detectors way
back, possibly ?