Set screw broke in motor shaft
#1
Member
Thread Starter
Set screw broke in motor shaft
Hi everyone,
We have a central AC unit in the house. The heat is a separate unit which is hot water base board heat (gas).
The AC was making a loud noise from the air handler in the attic. I opened it up, pulled the blower motor / blower wheel assembly out and it looks like the set screw that holds the blower wheel onto the motor shaft broke. Part of the set screw is inside the shaft (like the screw snapped off). Before replacing the whole assembly (looks like the motor is $760 and fan is $124 ), do you think I have any options here? Is it possible to get that broken piece out of the shaft? Maybe with one of those "broken screw removal tools"? Or possibly drill through it and use a nut and bolt instead of a set screw? Or perhaps you can't drill through that shaft? Just thinking out loud.
Hopefully you can see the picture of what I'm talking about attached.
Thanks!
We have a central AC unit in the house. The heat is a separate unit which is hot water base board heat (gas).
The AC was making a loud noise from the air handler in the attic. I opened it up, pulled the blower motor / blower wheel assembly out and it looks like the set screw that holds the blower wheel onto the motor shaft broke. Part of the set screw is inside the shaft (like the screw snapped off). Before replacing the whole assembly (looks like the motor is $760 and fan is $124 ), do you think I have any options here? Is it possible to get that broken piece out of the shaft? Maybe with one of those "broken screw removal tools"? Or possibly drill through it and use a nut and bolt instead of a set screw? Or perhaps you can't drill through that shaft? Just thinking out loud.
Hopefully you can see the picture of what I'm talking about attached.
Thanks!
Top Answer
06-01-20, 08:16 AM
Group Moderator
I do not see anything broken. That is how items are held on a shaft. The flat spot on the shaft is where the set screw goes. When you tighten a set screw onto a shaft it creates a burr (the circle you think is broken set screw) which can make the part hard to remove, it's just the imprint of the end of the set screw. The flat spot on the shaft is there so there is clearance above the burr so it doesn't bind the part on the shaft.
#2
Hard to tell from the picture!
Sort of looks like the motor shaft is square but it would then not align to the set screw.
Plus whatever that is int the shaft doesn't look broken and the dia is different from the screw, usually there is a keyway between the shaft and wheel!
Sort of looks like the motor shaft is square but it would then not align to the set screw.
Plus whatever that is int the shaft doesn't look broken and the dia is different from the screw, usually there is a keyway between the shaft and wheel!
#3
Group Moderator
I do not see anything broken. That is how items are held on a shaft. The flat spot on the shaft is where the set screw goes. When you tighten a set screw onto a shaft it creates a burr (the circle you think is broken set screw) which can make the part hard to remove, it's just the imprint of the end of the set screw. The flat spot on the shaft is there so there is clearance above the burr so it doesn't bind the part on the shaft.
#4
Member
Thread Starter
Thanks for the replies guys.
@Pilot Dane - I can't figure out how to quote your reply, but "in theory" should I just be able to screw that set screw into that same spot then? Or do you think it's more likely that the blower wheel has failed and needs to be replaced? Sorry, I know you don't have a crystal ball.
@Pilot Dane - I can't figure out how to quote your reply, but "in theory" should I just be able to screw that set screw into that same spot then? Or do you think it's more likely that the blower wheel has failed and needs to be replaced? Sorry, I know you don't have a crystal ball.
#5
Group Moderator
That flat on the shaft is there so you can easily put things on or off of the shaft. If the blower wheel is in good shape you should be able to put it back on. It's possible the set screw worked loose over time and allowed the blower wheel to slide out and rub. You can use blue Loctite on the set screw to help prevent it from vibrating free. Do not use other stronger types of Loctite (red) as it can make it impossible to disassemble without a torch.
#6
It's possible the set screw worked loose over time and allowed the blower wheel to slide out and rub.
#7
Member
Thread Starter
Do you think the motor is still ok then? The contractor implied that the motor shaft probably now has a problem and we need to replace the motor along with the blower.
Here's a video of the awesome sound it was making if you're interested (disregard my socks) :-
https://youtu.be/uz6eO1b9AGk
Here's a video of the awesome sound it was making if you're interested (disregard my socks) :-
https://youtu.be/uz6eO1b9AGk
#8
Nice socks.
Sounds like a loose wheel on the shaft. Put the setscrew back in place. Slide the wheel where it's centered in the opening and tighten the setscrew.
Sounds like a loose wheel on the shaft. Put the setscrew back in place. Slide the wheel where it's centered in the opening and tighten the setscrew.
#9
Member
Thread Starter
So I tightened the set screw to hold the blower wheel onto the shaft. When I turned The unit back on, the blower wheel spins, but it’s very loud and wobbly. So I think it’s just a blower wheel, and probably not the motor. I took the blower wheel and motor out of the unit and ran the motor just on its own to see if it wobbled at all, and it looks completely fine to me. Trying to see if I can just buy the blower wheel from somebody local to Denville New Jersey. So far I called Universal Supply in Wharton, and they don’t sell parts for Heil. I tried Sid Harvey in Wharton, but they don’t sell to consumers. I also tried Mr. Appliance in Rockaway but they don’t sell parts for that brand either. Know any other places that would sell to a consumer in the Denville area?
Here are a few videos that I took: This one shows that the motor seems to be ok (spins fine and doesn’t wobble):
https://youtu.be/YTkxIJJND4o
This one shows the blower wheel being “wobbly“:
https://youtu.be/9tXhYFJ29zk
This one shows that the shaft of the motor still spins, even though the blower wheel is tightened onto the shaft:
https://youtu.be/fdS0V5NQrLk
Here are a few videos that I took: This one shows that the motor seems to be ok (spins fine and doesn’t wobble):
https://youtu.be/YTkxIJJND4o
This one shows the blower wheel being “wobbly“:
https://youtu.be/9tXhYFJ29zk
This one shows that the shaft of the motor still spins, even though the blower wheel is tightened onto the shaft:
https://youtu.be/fdS0V5NQrLk
#10
Yes..... unfortunately the wheel has become loosened from the mounting hub.
I haven't seen any make or model posted in this thread.
I haven't seen any make or model posted in this thread.
#11
Member
Thread Starter
The air handler is a Heil. Attached is a picture of the manufacturing label. Looks like in the top left the model number is BA3036SKA1 if I’m reading that correctly.
#12
I see several possible substitutes.
Be sure to measure the length and diameter of the old one.
Measure shaft size.
When ordering have the full model number as well as the serial number.
blower wheel
Blower wheel
Blower wheel
Be sure to measure the length and diameter of the old one.
Measure shaft size.
When ordering have the full model number as well as the serial number.
blower wheel
Blower wheel
Blower wheel
#13
Member
Thread Starter
Thanks PJmax!!!
1. That first link has a bunch of Rheem wheels. Can you use a wheel that’s not a Heil as long as it’s the right size? Or is that a no-no?
2. You said to measure the shaft size. Is that the length, diameter, or circumference? :-)
3. These sites say “bore” size. Is that the size (diameter?) of the hole in the wheel for the motor shaft?
Thanks again!
1. That first link has a bunch of Rheem wheels. Can you use a wheel that’s not a Heil as long as it’s the right size? Or is that a no-no?
2. You said to measure the shaft size. Is that the length, diameter, or circumference? :-)
3. These sites say “bore” size. Is that the size (diameter?) of the hole in the wheel for the motor shaft?
Thanks again!
#14
Group Moderator
1. You can use most any wheel that's the proper size and rotation.
2, The shaft size is measured by it's diameter and length.
3. Bore size is the hole in the center to accept your motor's shaft. For example if your shaft measures 1/2" diameter you will need a wheel with a 1/2" bore. In actuality the bore in the wheel will be slightly oversized so you can slide it on the shaft.
When shopping for a wheel you'll need to know the wheel's outer diameter. The width of the wheel/blades. Also pay attention to any offset in the wheel's mounting hub. Some have the mounting hub flush with one end while others are offset so the fan wheel can be mounted closer (even up around a bit) to the motor. And, don't forget the rotation direction. Everything I can remember rotated in the same direction but I like to double check to make sure. You'll want the angle direction of the fan blades to be the same as your old wheel.
2, The shaft size is measured by it's diameter and length.
3. Bore size is the hole in the center to accept your motor's shaft. For example if your shaft measures 1/2" diameter you will need a wheel with a 1/2" bore. In actuality the bore in the wheel will be slightly oversized so you can slide it on the shaft.
When shopping for a wheel you'll need to know the wheel's outer diameter. The width of the wheel/blades. Also pay attention to any offset in the wheel's mounting hub. Some have the mounting hub flush with one end while others are offset so the fan wheel can be mounted closer (even up around a bit) to the motor. And, don't forget the rotation direction. Everything I can remember rotated in the same direction but I like to double check to make sure. You'll want the angle direction of the fan blades to be the same as your old wheel.
#15
Member
Hello from Denville also !!! Try contacting Johnstone Supply or Ferguson might also be a good local source.
#17
Member
Thread Starter
Thanks everyone for all of the help. I called about 10 places. Five of them wouldn’t sell to homeowners (you had to be a contractor), and the other five didn’t sell parts for Heil. I was able to find an original blower wheel at Fergusons plumbing (they would order it for me). Ultimately though, I called the contractor back to put the blower wheel in, which worked out fine. I was disappointed to see though, after he left, that he did not install a small piece of sheet metal that was there to direct the airflow a little more “directly”. So, I opened it back up, put the piece of metal in, and reinstalled it. Good to go. I’m also surprised that all of the stores that didn’t sell Heil didn’t think to just sell me an aftermarket brand blower wheel. That’s what the contractor brought with him. Anyways, thanks again for help!
#18
Nothing is broken.
The end of the setscrew is cupped so it digs into the shaft and leaves that telltale mark.
Just dress that spot with a file and you're good to go.
The end of the setscrew is cupped so it digs into the shaft and leaves that telltale mark.
Just dress that spot with a file and you're good to go.