Furnace blower motors and capacitors are straight forward furnace parts that can be swapped out with some basic information.
When buying a new furnace blower motor the old blower motor face plate will need to be examined.
If you cannot find an exact model number replacement, a universal replacement motor that matches the HP, RPM, Amp, Voltage, Speed along with shaft size will need to be bought.
If you can find an exact model number replacement, you are done; you will simply need to order it.
If you can’t find an exact model number replacement, an equal replacement will have to be found.
Motor manufacturers make universal blower motors that can be wired to run at a wide range of settings depending on how they are wired.
For example, if you have a 1/2 HP blower motor and can’t find an exact model replacement, you can buy a universal motor that runs at 1/4 HP,1/3, or 1/2 HP, depending on which wires from the motor are used.
Write down the following information from the tag on the motor when looking for a blower motor, then find one that matches your motor for a replacement.
Details Needed to Buy a Furnace Blower Motor
- RPM: If the motor has multiple speeds, then only the highest speed will be listed. Common motor speeds are 1200, 1075, and so on.
- HP: 1/8, 1/3, 1/4, or 1/2
- Amp: 5 uf, 6 uf, and so on
- Voltage: 120 Volts or 240 Volts
- Speed: 1 speed, 2 speed, or 3 speed
- Shaft size: Most furnace motors use a 1/2 inch, but sometimes they can be different.
Here is an example of a furnace blower motor on Amazon. You can see the listing description, and the specifications are listed for the motor.
Example Furnace Blower Motor On Amazon
A.O. Smith/Century DL1056 1/2 HP, 1075 RPM, 3 Speed, 115 Volts6.5 Amps, 48 Frame, Sleeve Bearing Direct Drive Blower Motor
How to Buy a Furnace Capacitor
Some furnaces do not use a capacitor, while others will have both a START and RUN capacitor. But most furnaces by far have a single capacitor.
Capacitors are measured in voltage and “uf” (microfarads). To find a replacement, look at the capacitor and write down the voltage (120, 240, 370, 440) and the “uf” (4-10 amps) and then order a replacement.
Here is an example capacitor that is 370 volts 5 uf (microfarads).
Any capacitor that is 370 volts 5 uf can replace this capacitor. The same will apply to any other capacitor; simply match the voltage and microfarads.
(The part that says +-5% is what the capacitor is rated to go up or down from.)
Any capacitor that matches yours in voltage and amps will work.
Here is an example on Amazon; as you can see in the listing description, it shows the uf and voltage.
Example Furnace Capacitor On Amazon
Genteq Capacitor 10 UF MFD 370V
Where to Buy a Furnace Blower Motor and Capacitor
I like to buy my parts from Amazon and sometimes eBay; the parts are much cheaper compared to an HVAC supply store.
If you are in a hurry, you can buy the parts at an HVAC supply store. Some do not like to work with Non-HVAC people because of damaged parts being returned, while others will not care.
If you can wait a few days for parts to be delivered, then I would suggest Amazon or eBay.