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.

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. This video shows how to wire a furnace blower motor to an extension cord how to reverse the rotation what informa. 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 white wire connects to the w terminal the yellow wire connects to the y terminal and the common wire is used with digital thermostats and is usually black or blue.

Step 5 run an additional wire from the furnace to the terminal in the thermostat labeled g. It shows the parts of the circuit as streamlined shapes and the power as well as signal connections in between the devices. Furnace fan limit switch wiring diagram wiring diagram is a simplified tolerable pictorial representation of an electrical circuit it shows the components of the circuit as simplified shapes and the power and signal connections amongst the devices. The fan or furnace blower motor is controlled by the two left connections green dots.

A wiring diagram is a simplified traditional pictorial representation of an electrical circuit. Here the furnace limit switch is controlling a line voltage device. Assortment of furnace fan motor wiring diagram. Assortment of furnace blower motor wiring diagram.

The furnace has 2 speeds low for heating and high for cooling. 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. The furnace limit switch which will turnoff the burner if the temperature limit is reached is controlled by the two right connections red dots. If the furnace is easily accessible you could mount a toggle switch on the furnace cabinet.