Fan limit switch gets stuck occasionally, repair or replace?

[SecondPondRoad]

New-to-us house with a Newmac WB100, wood only. According to a manual we found online, the fan limit switch is an L4064, 11". The installed switch is a White-Rodgers, just a lever control. Looks clean and new. But sometimes (not every time) when the firebox is loaded, or getting cool, we eventually have to lightly knock the switch casing, because we know bloody well the blower should be doing the opposite of whatever it's doing. Just like tapping a barometer to get the needle to move. Then it's fine for ages, cutting the blower in and out logically and normally. Can we fix it or does the whole lot need replacing?

 

[brenndatomu]

You could try pulling it out, looking for an issue with it, maybe blow it off with compressed air if its all dusty...other than that I'd tend to lean toward replacing with the original Honeywell switch

 

[Niro]

I would open it up and taking a look inside. Maybe just needs some compressed air and Cleaning.

If you see serious damage like a short or melting of plastics then replace.

Turn off breaker first.

 

[SecondPondRoad]

You could try pulling it out, looking for an issue with it, maybe blow it off with compressed air if its all dusty...other than that I'd tend to lean toward replacing with the original Honeywell

You could try pulling it out, looking for an issue with it, maybe blow it off with compressed air if its all dusty...other than that I'd tend to lean toward replacing with the original Honeywell switch

Thanks! I am thinking that because a tap will fix it, the problem is probably with a moving trigger part, not the sensor rod part. That little wheel gizmo looks delicate, likely no good will come of me messing with it