Harman PF100 Fan/Limit switch

[nateschisler]

So newly installed PF100 is up and running strong. Got a defective thermostat so running on "service" mode until my dealer gets a new one in. Noticing some quirky behavior from the fam/limit switch. It appears to be "sticking". I'll have a smaller fire going (say 2 or 3 on the dial) and the blower won't kick on. If I tap the switch, the dial jumps over to what I expected the temp to read (130 range) and kicks the blower on. Can this thing be greased or lubricated? Perhaps some WD-40 on the moving parts.

Is there such a thing as a digital fan/limit switch...I think that would be a nice upgrade and provide more consistent heat?

 

[bwep]

Sounds like the contacts are sticking, no really a sevicable item. I would replace it with a new one. If it's new have them replace it under waranty. Never saw a limit switch digital, not saying they dont exist, it would be cool.

 

[Ejectr]

So newly installed PF100 is up and running strong. Got a defective thermostat so running on "service" mode until my dealer gets a new one in. Noticing some quirky behavior from the fam/limit switch. It appears to be "sticking". I'll have a smaller fire going (say 2 or 3 on the dial) and the blower won't kick on. If I tap the switch, the dial jumps over to what I expected the temp to read (130 range) and kicks the blower on. Can this thing be greased or lubricated? Perhaps some WD-40 on the moving parts.

Is there such a thing as a digital fan/limit switch...I think that would be a nice upgrade and provide more consistent heat?

My fan controller was doing the same thing. If you seperate the on off a little bit more on the settings instead of their recommended gap of "over the center 0 in 100", it works better. That book setting is only a suggestion. I have mine set to turn on at 155 degrees and off at 115 degrees and it keeps the fan from running constantly like it does on the over the 0 setting in the book. I talked to Harman about it and they suggested 115 -120 on the off and 155 - 160 on the on with the overtemp against the safety screw. Got the wall controller set to 70 and by gosh, that's what it keeps the digital thermometer at with no tinkering.

 

[kinsmanstoves]

So newly installed PF100 is up and running strong. Got a defective thermostat so running on "service" mode until my dealer gets a new one in. Noticing some quirky behavior from the fam/limit switch. It appears to be "sticking". I'll have a smaller fire going (say 2 or 3 on the dial) and the blower won't kick on. If I tap the switch, the dial jumps over to what I expected the temp to read (130 range) and kicks the blower on. Can this thing be greased or lubricated? Perhaps some WD-40 on the moving parts.

Is there such a thing as a digital fan/limit switch...I think that would be a nice upgrade and provide more consistent heat?

Are you refering to the fan limit control switch (on the plenum) or the thermostat (on the wall).

Do not go by what the manual suggests on setting the fan limit control switch. This has to be done by the air temp coming out of the ducts.

There is no digital thermostate available for the PF-100 at this time.

Eric