Hvac Fan Limit Switch Location

It also determines if the furnace should be shut down in the case of overheating.

Hvac fan limit switch location.

It s possible to reset the switch at home when necessary by following a few simple steps. It works off of temperature and also provides a high temperature safety limit this is a switch actually two switches which turns the furnace blower on and off based on the temperature of the heat exchanger. Once the plenum reaches a specific temperature the limit switch sends a signal to the air handler to begin running and delivering warm air to your home. It reads the temperature of the plenum and waits until it gets appropriately warm.

However for your own safety don t attempt to reset the switch without first consulting your furnace s instruction manual. 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. A limit switch also acts as. By saum hadi posted on august 31 2018.

The fan limit switch also has two other functions. A fan limit switch consists of the following components. Most types of residential furnaces feature an internal component known as a blower switch that is used to shut down the fan motor in the event that the appliance overheats the motor malfunctions or the furnace filter becomes clogged. How a fan limit switch works.

Fan and limit control 8 limit control 14 multiple appliance interlock control 2 plenum thermostat 10 snap disc control 51 temperature transducer 3 thermostat 2 universal interlock control 1 warm air limit control 1 view all. A limit switch is a device that s located under your furnace s supply plenum. 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. Honeywell furnace temperature fan limit switch control the fan limit control turns the fan on and off in furnace applications.

Goodman gmt115 5 fan randomly turns on doityourself. The oil fired furnace fan limit switch shown in our photo below is in use on an oil fired warm air furnace where we can see about 3 4 of the silver colored dial where the fan limit switch settings are made red arrow. To restore the furnace to normal operation you must reset the switch on the blower motor. Just as it determines when the blower assembly should turn on it will also determine when it should turn off.

Goodman gms81005cn 100 000 btu furnace 80 efficiency single. A helical bi metal probe extends from the back of the. Test and replace the fan limit switch on a furnace hvac how to.