High Frequency noise coming from Maxxair fan

**screamineagle** · 06-21-2020, 07:05 AM

This is driving us nuts. We have a 2020 momentum 395. The ceiling fan motor in the main area is giving off a high frequency whine on slow and intermediate speed. We have contact Lippert on the problem and we have been sent new motors to fix the problem. All the motors do the same thing. It is not the hardware or the housing the motor sits in. I have held these motors in my hand to put my ear right to it and you can clearly hear the issue. My wife has better hearing than myself and it is driving her nuts rendering the fan useless. Has anybody else had this issue and has it been resolved? I am running out of ideas.

**jkwilson** · 06-21-2020, 08:08 AM

My first thought is an issue with the speed control. I don’t know how they control speed, but my guess would be pulse width modulation. PWM controls can cause motor acoustic noise when the drive pulse isn’t smoothed properly. This would either be a result of bad design or a failed part within the fan electronics.

**screamineagle** · 06-21-2020, 08:47 AM

Googling it I have seen other people with the same issues. I also had an issue with my slide hydraulics not having the correct fuse setting in the one control system. Can a fuse setting cause this sort of thing?

**jkwilson** · 06-21-2020, 01:20 PM

Originally Posted by screamineagle

Googling it I have seen other people with the same issues. I also had an issue with my slide hydraulics not having the correct fuse setting in the one control system. Can a fuse setting cause this sort of thing?

Not a fuse.

Do you have another Maxxair you can try the motor in? I think it’s a problem with the fan electronics, but I’m not sure they’ll buy it unless you can demonstrate the motor is quiet in another fan.

**bcdiesel** · 06-21-2020, 11:19 PM

Same issue with my kitchen Maxxair fan. High pitched squealing on the first 3 speeds... only disappears on max speed. I tried “burning in” the motor as suggested on forums for 24 hours at high speed but no change. I gave up and just use it as a roof vent now without the fan.

**screamineagle** · 06-23-2020, 04:03 PM

Well, I am on my third fan motor. New circuit board sent to me. Same thing. I guess I'm booting it to Grand design

**DaveMatthewsBand** · 06-23-2020, 07:41 PM

Originally Posted by screamineagle

This is driving us nuts. We have a 2020 momentum 395. The ceiling fan motor in the main area is giving off a high frequency whine on slow and intermediate speed. We have contact Lippert on the problem and we have been sent new motors to fix the problem. All the motors do the same thing. It is not the hardware or the housing the motor sits in. I have held these motors in my hand to put my ear right to it and you can clearly hear the issue. My wife has better hearing than myself and it is driving her nuts rendering the fan useless. Has anybody else had this issue and has it been resolved? I am running out of ideas.

As I understand it, those motors are NOT brushless, so what you are hearing is dust buildup on the rotor shaft thingamajig.

It’s a 30-minute fix with some compressed air and it’s good as new.

Here’s the video I followed to fix mine.

https://youtu.be/7Z18GcgNj5Y

Sent from my iPhone using Tapatalk

**screamineagle** · 06-24-2020, 04:13 AM

Thanks, I am familiar with that issue and yes it is common over time. All the motors were brand new, I did take one apart to check, spotless. This is a very high frequency scream that virtually only certain ears can hear. And it only does it on low and medium speeds.

**screamineagle** · 06-24-2020, 04:18 AM

Don't you feel that with numerous people complaining about the same thing that giving up caves to the manufacturer. I don't know about you but all said and done I've got 80K invested in this unit and another 70 to pull it. Its nonsense. And really starting to upset me.

**Tigger1** · 06-24-2020, 04:45 AM

Originally Posted by screamineagle

Don't you feel that with numerous people complaining about the same thing that giving up caves to the manufacturer. I don't know about you but all said and done I've got 80K invested in this unit and another 70 to pull it. Its nonsense. And really starting to upset me.

Oh boy, after reading your thread I’m keeping my fingers crossed. Today I’m installing a MaxxFan Deluxe to replace the crappy small roof computer fan that came with it. I’ll be listening.......