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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I have a fedders f80A 100-3 furnace. That turns on and off

Customer Question

I have a fedders f80A 100-3 furnace. That turns on and off after a couple of minutes. The hot surface ignitor has been recently replaced and the flame sensor has been cleaned.
JA: Did you check the furnace's filters?
Customer: Yes I replaced the intake filter in the house. Is there another filter?
JA: Do you plan on doing the work yourself?
Customer: I am attempting to do as much as I can
JA: Anything else we should know to help you best?
Customer: It is a gas furnace
Submitted: 9 months ago.
Category: HVAC
Expert:  Phil replied 9 months ago.

Hello, there might be another air filter where the return air duct attaches to the furnace or inside the blower compartment.

does the furnace keep turning on and off, or do you have to do something to get it going again.

Customer: replied 9 months ago.
The furnace keeps turning on and off by itself.
Expert:  Phil replied 9 months ago.

Thanks, ***** ***** temporary jumper wire across each switch in the 24v circuit until the problem ceases... it will be that last switch that needs to be replaced.

Just follow the 24v wires around to locate all of the switches.... thermostats, high temperature limit switch and any others in series with those two