Variable speed control making ceiling fans noisy? - Electrician Talk - Professional Electrical Contractors Forum

Landmark · 05-31-2011, 08:02 PM

I replaced two old 3-speed 5 amp fan controls that controlled 5 ceiling fans each in a small retail store. My supply house ordered me infinitely variable speed switches ( 5 amp Lutron ). The old ones were slide switches with off-lo-med-hi.
Now when the fans are on high they work fine. When you adjust the speed a little lower the fans start to make a humming or slight buzzing sound.
Anyone else had this problem?

**Dennis Alwon** · 05-31-2011, 08:06 PM

Quote:

Originally Posted by Landmark

I replaced two old 3-speed 5 amp fan controls that controlled 5 ceiling fans each in a small retail store. My supply house ordered me infinitely variable speed switches ( 5 amp Lutron ). The old ones were slide switches with off-lo-med-hi.
Now when the fans are on high they work fine. When you adjust the speed a little lower the fans start to make a humming or slight buzzing sound.
Anyone else had this problem?

That will always be a problem with variable speed controls. They make the fans hum. I called Lutron and said they are used mostly in commercial applications where noise is not an issue. You need to go back to the selected speed control

InPhase277 · 05-31-2011, 08:09 PM

Quote:

Originally Posted by Landmark

I replaced two old 3-speed 5 amp fan controls that controlled 5 ceiling fans each in a small retail store. My supply house ordered me infinitely variable speed switches ( 5 amp Lutron ). The old ones were slide switches with off-lo-med-hi.
Now when the fans are on high they work fine. When you adjust the speed a little lower the fans start to make a humming or slight buzzing sound.
Anyone else had this problem?

Yeah but it isn't a problem, per se. It is the result of the PWM electronics that control the fan speed. The frequency that is used to regulate the motor speed is at the mid to high end of the sound spectrum, so instead of the regular 60 Hz hum, we can hear the higher pitched buzz from the motor. Kinda like a speaker.

**480sparky** · 05-31-2011, 08:09 PM

As Dennis says, those variable speed controls will always have a problem with noise. Get the 3-speed preset models and you'll eliminate 98% of the issue.

Landmark · 05-31-2011, 08:10 PM

Thanks Dennis!
Who makes a 5 amp control like this?

Smoke · 05-31-2011, 08:11 PM

Quote:

Originally Posted by Landmark

I replaced two old 3-speed 5 amp fan controls that controlled 5 ceiling fans each in a small retail store. My supply house ordered me infinitely variable speed switches ( 5 amp Lutron ). The old ones were slide switches with off-lo-med-hi.
Now when the fans are on high they work fine. When you adjust the speed a little lower the fans start to make a humming or slight buzzing sound.
Anyone else had this problem?

i came across this long ago, only way i found to fix it was to get the speed control from the fan manufacturer.

220/221 · 05-31-2011, 08:19 PM

Quote:

Originally Posted by Landmark

Anyone else had this problem?

Yes, once.

Don't use variable speed...problem solved.

**frenchelectrican** · 06-01-2011, 01:05 AM

Just make sure you get dehummed verison they will be little more quiet as well but get in tri speed verison not the vari speed at all.

I found out in hard way many years ago with the ceiling fans.

The cheap ceiling fans tend to be more noisier than well builted fans are.

The most recent one I work on was old school Hunter cast iron ceiling fan that thing you can not really hear it very well pretty quiet { I can able pick up the vibertions when it was running so I know it still running }

Merci,
Marc