Furnace Fan Limit Switch Replacement

How to diagnose and repair the furnace fan limit switch.

Furnace fan limit switch replacement.

Emerson 5d51 35 universal replacement fan and limit control with 5 element. Honeywell l4064b2228 forced air fan and limit controller. 025 29041 004 york oem furnace 3 replacement limit switch l160. When fan is set to auto furnace shuts down within about 1 5 min of starting with red status light blinking 4 times limit switch open code.

Locate the furnace fan limit switch. How a fan limit switch works. It s possible to reset the switch at home when necessary by following a few simple steps. However for your own safety don t attempt to reset the switch without first consulting your furnace s instruction manual.

The function of your furnace limit switch is to tell the fan when to turn off and on depending on the temperature in the home. The switch is mounted on the furnace air plenum and is easily recognized because of its wiring once the access panel has been removed. Get it as soon as fri sep 25. In this episode of repair and replace vance shows how to replace the high limit switch in a gas furnace.

Two of the wires are low voltage and go to the limit switch and two wires are line voltage and go to the fan switch. Verified resistance of 0l on limit switch after switch was reset from powering down furnace. Just as it determines when the blower assembly should turn on it will also determine when it should turn off. This is used so that cold air is not blown into a house waiting for the gas flames to heat up enough before the blower turns on.

But it works fine when fan is set to on. It also determines if the furnace should be shut down in the case of overheating. 4 8 out of 5 stars 5. 4 8 out of 5.

Fan control limit switch the fan switch reads the temperature inside a furnace and once the temperature becomes warm enough turns the blower motor on sending warm air into a home. The limit switch is a safety switch that monitors t. 4 8 out of 5 stars 21.