Why does my HVAC blower fan not work?

Why does my HVAC blower fan not work?

Measure voltage between C (or the common side of the transformer), and the wire that was connected to Y. You should get about 24 volts AC. If you don’t there’s a problem with the thermostat, or the wire between the thermostat and furnace. If you do, then the problem likely lies within the control board.

How many volts does a blower fan need?

You should be getting 120 volts out of the control board. You can test by testing with a voltmeter set to “Volt AC” between the high-speed blower wire (usually black) and the white neutral wire.

When do you need a new blower motor?

If you are getting 120 volts to the motor and it is not starting then you have a blower motor problem and either need another new blower motor or a new blower motor run capacitor. If you are not getting voltage to the blower motor out of the control board then you probably need a new control board again.

How does a thermostat turn on a blower fan?

If the W terminal is energized, it turns on the heat and the fan at the furnace. If the Y terminal is energized, it turns on the a/c outside unit, but not the blower fan. Typical thermostats will energize the G terminal when in cool mode, or when the fan is turned to manual “always on” mode.

Why is my a / C not blowing any air?

Sometimes it’s in the actual mechanical part of the A/C. And sometimes it’s only in the “air movement” part of the system. If you are not getting any air blowing out the vents but the vents feel cold, AND you can hear the blower fan running, then it might simply be a restricted cabin air filter.

What happens if heater blower motor does not work?

Therefore, if major problems in the heating and air conditioning system fail, as if the power supply to the motor was completely cut off due to overheating or corrosion, the motor will simply not work, which in turn will render the entire heating and air conditioning system unusable, as no air will flow through the vehicle’s air vents. 2.

What should I do if my blower fan wont come on?

You will need to test with a voltmeter and see if your fan motor is getting the required 110 to 125 volts AC out of your control board to start the motor. I would suggest setting your thermostat to the “Fan ON” position. You should be getting 120 volts out of the control board.

If you are getting 120 volts to the motor and it is not starting then you have a blower motor problem and either need another new blower motor or a new blower motor run capacitor. If you are not getting voltage to the blower motor out of the control board then you probably need a new control board again.