Furnace Blower Furnace Fan Limit Switch Wiring Diagram

As the air in the furnace plenum warms up the bimetallic spring expands turning a gear which turns the fan limit control dial shown in the photo above.

Furnace blower furnace fan limit switch wiring diagram.

This video shows how to wire a furnace blower motor to an extension cord how to reverse the rotation what informa. How to wire a furnace or ac blower motor. It shows the parts of the circuit as streamlined shapes and the power as well as signal connections in between the devices. If the furnace is easily accessible you could mount a toggle switch on the furnace cabinet.

The furnace has 2 speeds low for heating and high for cooling. The furnace limit switch which will turnoff the burner if the temperature limit is reached is controlled by the two right connections red dots. Diagram b fan control wiring in old style us series heaters with serial numbers having prefix d motor overload switch takes place of limit control by breaking cir multiple furnace installation may use a group of up to use the provided unit wiring diagram and the field wir dip switch 1 wiring connections w915 y1 to y2 two stage cooling w914 ds to r dehumidifi cation or harmony iii w951. Assortment of furnace blower motor wiring diagram.

It would seem easier to just run another thermostat wire and get a thermostat with a fan switch than to install another switch on the wall. A wiring diagram is a simplified traditional pictorial representation of an electrical circuit. Assortment of furnace fan motor wiring diagram. Here the furnace limit switch is controlling a line voltage device.

The fan or furnace blower motor is controlled by the two left connections green dots. Step 5 run an additional wire from the furnace to the terminal in the thermostat labeled g. Standard ac with standard furnace control wiring standard furnace standard thermostat standard a c condenser 1st stage heat white 24 volt fan only operation common air conditioning ac contactor control board 1 this diagram is to be used as reference for the low voltage control wiring of your heating and ac system. The fan limit switch contains a bi metallic spring shown at left which is inserted into the warm air plenum of the heating furnace.