Why is my AC blower not turning on?

Why is my AC blower not turning on?

First make sure there is power to the indoor unit and that a switch or breaker isn’t off. Try setting the thermostat fan switch to the “on” position. Feel for air coming out of the vents. If it is in the air conditioning mode, check for ice around the evaporator coil and on the refrigerant lines at the indoor unit.

How to diagnose a bad blower motor switch?

Symptoms of a bad heater blower motor resistor

  1. Fan does not work at all, so no air comes out of the vents.
  2. Fan only works on some speeds and not others.
  3. Fan only works on the highest speed.
  4. Fan runs all the time and can’t be controlled with the fan switch.
  5. You see smoke coming out of the vents.

Why does my fan blower not come on?

If it does not come on then you might have a control board fan relay that is not sending 120 volts to the blower motor or a bad blower motor winding. You might try to change wires (speeds) on the blower motor to see if that fixes the problem.

What happens when a blower motor resistor fails?

The blower motor resistor is the component directly responsible for controlling the blower motor fan speed. If the resistor shorts or fails, it may cause the blower motor to remain stuck on one fan speed.

What should I do if my Furnace Fan does not come on?

1. Make sure that your furnace switch is “ON” the furnace blower compartment door is on and secure. Move the lever on the thermostat to the “ON” position. The fan blower should come on. If it doesn’t then you probably have loose or burnt wires in behind the relay or you may need a new fan relay or circuit board.

What should the voltage be on my fan blower?

You should get a voltage reading of approximately 24 volts AC. If you do not get any voltage reading, your low voltage transformer might need replacing or you are not getting high voltage to power the transformer.

Why is my furnace blower fan not turning off?

Limit Switch Issue | Furnace Blower Fan Wont Turn Off If the furnace overheats, then a limit switch will open. That will cause the burners or heat source to shut off and the fan to run until the limit switch closes again. In some cases, the limit switch will stick open, and this will cause the fan to run continuously.

Is there a way to turn off the blower motor?

My blower/heater motor switch will not turn off the blower nor willl it change the motor speed. It’s currently stick on high. Even if I turn the engine off and take out the keys the blower is still running. I had to discoinnect the battery to get it to stop.

Why does my blower not work at high speeds?

Blower works on slow speeds, but not on high speed. Check for bad fuse or bad high speed relay. Swap the high speed relay with another relay with the same part number. Also, check the fuse for the control side of the high speed relay. Make sure the ground side of the high speed relay is working. Blower works on some speeds but not others

You should get a voltage reading of approximately 24 volts AC. If you do not get any voltage reading, your low voltage transformer might need replacing or you are not getting high voltage to power the transformer.

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