How To Buy a New Furnace Blower Motor and Capacitor

By | February 8, 2023

How to buy a new furnace blower motor and capacitor
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.

The tag on the motor will have the needed information Horsepower, RPM, Voltage, and Amps.
The model number can also be used to find a replacement, but in many cases, old model numbers don’t match up with new ones.

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.

Blower Motor manufacturers make universal 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: 5uf, 6uf, 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 have a single capacitor.

Capacitors are measured in voltage and “uf” (micro-farads). 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 (micro-farads).
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

Furnace blower motors can be bought at an HVAC supply store, or online such as Amazon and eBay.

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.

Category: HVAC how to

About Aaron H. Benetti

Aaron H. Benetti an HVAC technician who has worked in the field since 1991. He began his career as an HVAC installer and later began doing troubleshooting and repairs. Around 2010, he began to write books on HVAC topics, mainly tutorials and how-to information. Currently, Aaron works as an HVAC tech and also writes many articles and posts for websites as well as books and videos on HVAC topics.

11 thoughts on “How To Buy a New Furnace Blower Motor and Capacitor

  1. Michael

    After compacitor was changed the blower started working for about an hour then started back doing the same thing as before it was changed……help

    1. Nathen Taylor

      It’s the blower motor going out when it gets warm it shuts down. When it cools off it starts working again. Usually caused by age or lack of air flow, plugged filter, plugged coil.

  2. Tom

    I have a really old (30 years) furnace blower motor that stops working. I couldn’t find any exact match from online. Can you provide a suggested replacement from Amazon or Ebay? The spec is as follows,

    MagneTek Universal Electric
    MOD. HA3J034N#
    115V 60HZ 7.5A 950RPM 1/4HP

  3. Thomas

    Can I replace a 1/3 hp blower moter , Full-Load Amperage: 5.2, with a 1/2 hp motor, Full-Load Amperage: 8.4, that I have (new)?

  4. Andy

    I found a bunch of X13 motors, but mine is a variable speed. Will that work as long as HP, Volts, amps, etc match?

  5. Dennie Griffin

    I have a blower motor with a 42 frame. Can I use a 48 frame instead as long as everything else matches up?

  6. Marsel

    My blower doesn’t turn on anymore. I can hear the sound that it looks like is getting the command but it doesn’t start. When I try to spin with hand seems to have alot bigger resistance that the blower motor of the other AC that works fine.
    The AC guy told me that this is a smart blower motor and costs 1-1.5k but it seems weird to me and wanted to give it a try myself.
    If I replace with a motor that matches all the parameters mentioned in this article, am I good or is there such thing as smart motor?

    1. Don

      If the tech seems shady, it might be best to call another HVAC company get a second opinion.

  7. R

    Is it acceptable to replace a certain power blower motor with a lower power universal motor? For example, replacing a 1/2 HP with a universal 1/4, 1/6, 1/8 HP? I understand a 1/2 HP can be replaced with a 1/2, 1/3, 1/4 by using the right wires to match the power, but what about the prior scenario? What would happen?

    1. Rod S.

      The replacement must have at least the same hp as the one you are replacing. A 1/2, 1/3, and 1/4 hp motor has the capacity to produce 1/2 hp, which is what is required when replacing a 1/2 hp motor. The 1/4, 1/6, 1/8 hp motor has only half of the power required, so it will not be able to handle the load and will burn itself up very quickly.

  8. Lawrence Hall

    Blower drive motor failed after capacitor blew up no markings at all

    My option is to match up a capacitor to the motor or replace the motor and get new all
    best choice


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