Furnace Limit Switch Settings

Slide the cover off the control switch.

Furnace limit switch settings.

It should be located near the top of. Open up the access panel on the furnace. Look for the fan limit control switch encased in a small rectangular box. Heating ducts are typically located in a home s basement or utility closet.

The limit switch includes a sensor in the heat exchanger to determine. How to reset a furnace limit switch step 1. Wood furnace fan limit switch settings. The other important function of the limit switch is to shut off the burners if the heat exchanger gets too hot a condition that can crack the piping in the exchanger effectively ruining the furnace.

Most slide off or unhook for easy access. How to set a fan limit control switch step 1. Locate the white limit switch. Locate your furnace s heating duct.

By keeping the fan off until the supply air plenum is warm the heating furnace limit switch prevents the furnace blower from sending chilly air into the building if the oil or gas burner has not sufficiently heated up the furnace heat exchanger and supply air plenum. By saum hadi posted on october 15 2018. Limit switch functions if the blower came on at the same time as the burner it would pump cold air through the house at first. Depending on your furnace model the.

When the air in the supply plenum drops to the lower setting on the limit switch the switch shuts off the fan until the next cycle begins.