How do blower resistors work?
How do blower resistors work?
Blower resistors are resistors which are used to control the fan speed of automotive blowers. The fan speed can be changed either by switching the blower resistor resistance mechanically using a rotating lever, or electronically by the air conditioning system.
What happens when a central air blower does not start?
The blower motor starts, turning fan blades that circulate cold air from the evaporator coils, through the home’s ductwork and into each room. If the blower motor fails to start, nothing happens. The living spaces gets uncomfortable as the cooling cycle stalls. Most thermostats control both central air and central heat.
What should the voltage be on a blower motor?
If those are OK than backprobe the blower motor connector and check for power on terminal 1. Check terminal 2 for a variable voltage, this should be 12v with the fan control knob on off and 5v or full ground on full. If that checks out replace the blower motor.
Can a blower fan be used on an AC?
So using the blower fan on an AC does not equate to using a regular fan. but if you are using some type of air purification module inside of your ductwork then running the AC fan only is a perfectly good way of getting a whole house effect of an air purifier. Should the fan be on when the AC is on? Yes.
What to do if the blower motor does not work?
Make sure all the access doors are securely fastened in place. Even if a door is slightly skewed or not quite locked into position, the microswitch may sense that the door is fully open. If so, it will prevent the blower motor from operating. If the thermostat, breakers and access panel doors check out, the blower motor itself may have failed.
What happens when the blower motor switch stops working?
When this happens, one or several of the blower fan speeds stop working. The cool thing is that diagnosing/troubleshooting the blower switch isn’t hard. The following circuit descriptions will help:
What happens when you turn the blower speed knob?
To be more specific, as you turn the blower speed knob… the blower switch ‘opens’ and ’closes’ two contacts. The opening and closing of these contacts is what diverts the incoming blower motor current to different resistors within the blower motor resistor assembly.
What to do if your air conditioner blower motor is not working?
Other options include removing the air conditioner blower motor from the AC unit and checking the label on the actual blower motor. Write this part number down for easy reference. Having the exact part number can save you both time and money, especially if you intend to get a professional installer to replace the blower motor for you.
How does an air conditioner blower motor work?
As explained in the HVAC Blower Motor Guide, an air conditioner blower motor and assembly is basically the fan inside the air conditioning system that forces the cooled air, via the AC cooling coil, through the vents and into the room space that is being conditioned.
