Thank you for taking the time and making the effort to post this video. This week I had the exact same symptoms of a bad furnace motor vice a bad capacitor. There are many videos about replacing the capacitor, but yours is about the only one that looks at the motor as the culprit. Last week, my 17-year old furnace motor began to sound and act just like yours. A direct substitution with a new capacitor did not solve the problem. I removed the motor and disassembled it. The front sleeve bearing had worn to the point where the rotor was rubbing against the stator (field winding) and the shaft was scored where it contacted the bearing - this generated the noise and even would cause the rotor to stop turning when starting up. Through observation and logic, your procedure is a great way to troubleshoot and decide to whether a capacitor is sufficient (the cheap fix) or a new motor (more expensive) will be needed. Thanks again!

I just wanted to give an atta-boy to the video poster. Your video helped me solve my non-working furnace when it was getting pretty cold. What was special about this video is that you clearly explained what setting the multimeter needed to be on and zoomed in to show the symbol on the multimeter. This was very important as many of us are not electricians or have training in multimeter settings. Most other videos only referred to checking the MFD values with your multimeter, assuming you have that kind of high end meter??? Yours clearly showed the setting and how to test the capacitor and the need to wait and let the capacitor charge up, as well as, what readings you should expect based on the printed label. In my case, when I tested the capacitor with the multimeter, it showed OL which I believe means open line. This conformed the capacitor was bad and was not reading the appropriate values. This was an important test because my capacity looks brand shiny new, no rust, no corrosion, and no bulging. Ever the HVAC parts salesman questioned if it was bad when I showed him the capacitor. He was surprised as well. So thank you for your well thought out video and showing the necessary steps for a beginner like me to learn. My repair cost me $11 for a new capacitor and I had heat 5mins after I got back with the new capacitor. Your video saved me a couple hundred dollars for a service call!

Thanks for this video. You saved me so much money! It was the capacitor on mine that went dead. 10 dollar part from true value and A/C is back on.

Thank you SO much! This was the exact sound my furnace was making! I changed the capacitor and when that didn't work, replaced the blower motor and voila! All fixed! Including the buzzing sound in your video was key in making me think I could fix this myself and it saved me a lot of money!

Thank you for this video because it gave me so much information on my own furnace you walked through everything enough to where I could understand it all so I do appreciate what you've done and it was a great video and I hope to see more from you in the future

Thank you for this helpful and easy to understand video.

Great video. I never knew I could test the blower motor on the bench like you have yours. Sweet! Thanks

Thank you for the video all the other videos I watch made it confusing this video was straight to the point made it easy for me to diagnose my problem which is a bad blower motor thanks again.

Thank You very much brother, Saved me a head ache.

thank you for sharing adam excellent video God Bless...

Thank you. This was really really good.

Thanks this is a very good video

Thanks AdamDiy this help me troubleshoot my air handler. it is making exact noise.

a more accurate description of what the run cap does is it provides a phase shift on the incoming AC to help create a rotating magnetic field.

This is exactly what my furnace sounds like.😢 I guess I am going to try to figure out how to replace it myself (both the blower and capacitor). Thanks for the video!

great video thank you

thanks for sharing great video

Crazy!!! You made my day!! Peace!!

I have the same hum on my Rheem blower motor. found bad bearings install new motor & matching start capacitor still has same hum. will start if you spin motor. what kind of voltage should be on terminals in start . any ideas?

ok i replaced my fan in my house last year at the end of the winter the one i took off didnt have a cap. but the one I replaced it with does have the wires for a cap but not one on it how would i go about finding either a replacement without a cap or the cap for the one i have someone pls its really cold in mn

Adam . I have a colman furnace in a mobile home but the back of the motor ( bracket end ) is what you see when you open it up. I dont see a way to slide it out . it all looks mounted in .. any ideas?

Thank you for your video. Question: for this motor cap, does it matter which wire goes for which terminal?

hi adamdiy i have a janitrol furnace i can't find my capacitor lol do all furnace have capacitor

First of all thank you for this video. Would give more detail information on the purpose of the capacitor and how it works? My multimeter doesn’t have a microfarad on it. I understand I can test resistance but afraid the capacitor is too low to use with my multimeter.

Just replaced motor and capacitor. There was a loud rumble when fan was running. I thought maybe motor/bearings were going bad. New motor was cross referenced from Grainger Industrial. Put new motor in. Better but still a rumble on start up. Could the blower wheel somehow be bad and or the housing it is in? All wires on motor were same except one. There was an orange one on old and a yellow one on new. When running, air flow from vents doesn't seem as forceful. Where do I go with that?

bro, i love you. ty

I have this problem right now. Is there a video on how to discharge the capacitor? Thanks

are the "two prongs" in this capacitor interchangeable? Mine doesn't label the common terminal.

Because of covid I can't get mine replaced right now. Do you think I should still use it?

Replaced blower motor and tested the capacitor and it tested good. Not sure if I trust it, so I went ahead and bought one. Replaced the capacitor, and still the new motor and new capacitor will not start makes a much more silent hum than the old motor but still will not turn. Next step I am going to replace the control board UNLESS you think it could be something else I am not seeing. Help Please!

You can also check the other speed taps to see if the motor is really bad. That is a 4 speed motor. You might luck out and be able to run on a slower speed.

Adam, did you discharge the cap before testing it with the mutli-meter? I saw the annotation about discharging. I understand you were measuring the capacitance (impedance) of the old capacitor; but not the current. I am just wondering about the discharge instructions in text, versus your actions (on the video) for clarity's sake. Great video!

Need help!!! I have 2 A/C units in my house, I just notice a homming like noice coming from the upper floor unit inside de attic. You can hear it clear were the A/C filter goes. And I smell like something got burn.

So the capacitor can cause the loud noise too? I just thought it was a power source for starting the fan? Sorry, if the question seems redundant. I can't hear and want to make sure nothing is lost in translation through tje closed captioning.

Is that capacitor a run or start capacitor?

I changed my capacitor. Didn't change anything. Here's my situation. The blower stars OK the first time it is needed each day. However a few minutes later, when it needs to come on again, it just hums. Bad motor? Doesn't want to start after it is warm? Help please. Would you simply assume the motor needs to be replaced? Thanks for your great videos!

can a capacitor not work just sometimes? mine is 20yrs old & I pulled the fan-inside unit - to clean. It was very dirty. A few times last week the fan didn't come on with the heater but when I kicked the fan cover a couple times it did come on. The motor is shockingly clean & spins freely. I will oil it anyway. can the fan fail to come on just from 20yrs of heavy caked dirt? I wanted to change the capacitor as long as it is out but can't read a lot of the info. It has 2 poles. I can see that it is a - Cambridge 621___4A, 7.5_____10%, 370V_50/60Hz, __4_/70'C, TYP___NS1P_, _L_ No E128031, MO7C10N0, MADE IN UK. With this info can you tell what I need to get to replace it?

If my old motor didn't have a capacitor and I need one for the new motor how do I know where to brown wires go on a capacitor

I saved this buzzing sound as into a musical bass for my music 🎵

Thanks for the great video... it's funny your work bench looks like mine, right down to the Gorilla glue. LOL

My house has a 50 year old motor and has NO problems at all!

Caps are made, big news. They are graded, on a +- scale. Lower the number the better the cap. Means it will be closer to the initial rating. A 10% cap is inferior to a 5% or a 3% cap. The cap you tested needs replaced. OEM installed a 12.5uf. It if isnt' that replace it.

What if the motor is outside of the blower, it's running it with a belt. There is no capacitor that I can see. Its making the same noise. Thanks

Ok, motor is bad, but it would be nice to hear about what might have gone bad inside the motor? Bearings shot? or did electric coils develop a problem.

How can i cross reference my old blower motor to something new

That cap is out of range buddy anything under 11.25 is less than ten percent go by the capacitor nameplate not just that what is close enough

My blower motor wont start unless I tap it or gently hit it please 😢help south texas heat

This is a great video, however I can't find the capacitor. I recently changed the one outside, so I know more or less what it looks like. I don't see it attached to the motor. There is a panel board directly on the motor that has the cables for different speeds, as well as black, brown, yellow, and green/yellow cables. Please help! My unit is Carrier fx4dnf025

Where do I lube

Thank you so much, I have the same loud noise on my heater, I call almost Heater company here in Town and when they come, They told me that THEY don't know where the noise come from and they charge lots of money. This Loud noise comes and go any time, At mid night or early morning or any time in the day..My Heater is a PRESTIGE HEATER. Please Help thank you.

I would just try to spin it by hand as fast as I could to get it going

Here’s a way to test if it’s the cap. Give the blower a good spin then turn it on. If it spins up to full speed, it’s the cap.

Usually what does first is the bearings I bet

What if it only makes a similar noise not quite the same and only once a day and it's cooling the house fine...? I already called a guy to come out her will be here tomorrow but I am always worried about these techs ripping me off.

This is what is happening right now on my motor

22 dislikes? HVAC repair dudes maybe? 😆

Is this from an ac unit? Everyone is saying furnace. But ac is making that noise

My Motor seems to run, but the wheel makes noise like its rubbing. wheel has play side to side. but motor shaft does not. capacitor lists 10uf but goes past 20 and didn't stop when metered. does the wheel have a bushing? capacitor issue a coincidence?

11.13 uf is lower than 12.5 uf -10% but I guess it doesn't matter?

the style of bearings that those blower motors is a joke.thats the whole issue

Capacitor does not have extra juice (1:02). You need to learn how it works before you teach others.

This person has no idea what a capacitor is and you should not pay any attention to him.

Thanks this is a very good video