Another possible replacement is part number 902909 or Camstat F558
3" Cam-Stat FAL3C05TD120A universal fan and limit control. Fan temp is adjustable from 90-120F. Limit is adjustable from 150-250F. Adjustable differential is 25-50 degrees. The two silver terminals are fan terminals and tie into the blower motor. The brass terminals are limit switch terminals and typically tie into wires coming from the gas valve.
Extends 3" into furnace. Back plate measures 2-3/4"x2".
This FAL3C05TD120A Cam-Stat switch can be used to replace all SPST FAL3 series combinations. Also may suffice as a replacement for Duo-Therm 3-8628 and 38628 and Nordyne 207021, 3-8947-1, 40T314, 626185, 6261850, 6264854 & 6261851 & 902909. The old Duo-Therm units may have an extra wire. This is because back in the day, the old units used a pre-heater to activate the fan switch in a timely manner.
If your old unit has a preheater, then cap those wires. The old units found on Duo-Therm units typically have a preheater, which is often just one yellow wire. The pre-heater is generally a tiny heat strip that stretches across the end of the old switch. Eliminate that wire(s).
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