The blower fan keeps running and will stop until the breaker is shut off for a while. It may run fine through its complete cycles for a day or two, but will do it again! The furnace hasn't been used for about 4 years. What needs fixed or replaced, and where do I find these parts? The trailer was built in 1974, is in fair shape, and located in Summersville, West Virginia. Help!

In something that old, the blower is controlled by a relay operated by a limit switch. Follow the lead from the motor back to a little box. It should have 4 wires, the one from the motor, one from the house wiring, one to the transformer, and one to the limit switch. If, with the power off, the line from the house and the lead to the motor have continuity, the relay is stuck. Take it to a electrical or HVAC supply, and let them match it. They should have at least a work alike. If it is open with the power off, them likely it is the limit switch. Follow its wire into the heat exchanger, and take it to the supply house. The older systems are cheaper and easier to fix.

The parts may not be available. Have an HVAC person change the system over to a Sequencer and get rid of all the old obsolete relays Etc.

Ihave a coleman electric furnace model #3500A818 the coils light up even when the thermostat is in the off position

Ihave a coleman electric furnace modle #3500A818 the coils light up even when the thermostat is in the off position

Bad sequencer

Part number 3115-3571 Sequencer

Sequencer controls the sequence in which the heating elements & blowers turn on. This one has the ability to control up to 2 blowers (H1-H4) and 3 heating elements (M1-M6). Replaces 3400-357,

I have a coleman furnace model 7655-856 think it a 1982 when it call for heat it light up but blower don't kick on .I cheeked blower motor and it run. What do I need to replace

baer1213: I suspect you have a bad fan switch. This is a temperature actuated switch which closes to turn the fan on once a certain temperature at the switch is reached.