Multiple ceiling fans on one switch

[steve_p]

I am looking a job where 6 ceiling fans in two areas are required.

The owner wants to switch 3 at a time, basically two zones, two switches.

An EC I was talking to mentioned he had problems with more then one fan on a switch, stating that the fans failed prematurely.

There will not be speed controls involved, simply an on/off switch.

Has anyone experienced this?

Steve

 

[infinity]

An EC I was talking to mentioned he had problems with more then one fan on a switch, stating that the fans failed prematurely.

There will not be speed controls involved, simply an on/off switch.

I'd be curious to know how could this have anything to do with premature fan failure?

 

[steve_p]

I was curious myself. The EC also stated another EC he new had the same experience.

Well, I could not figure out why this would happen and thought I should ask here.

Thanks

 

[Dennis Alwon]

I could see problems with fan controls but what difference does it make if you are installing standard switches. It would be like saying you cannot have 3 fans on one breaker with no switch.

I have seen issues with remote controlled fans. If you try and use one remote for 3 fans on the same frequency the fans can get out of sink but not with a switch and no remotes or fan controls.

 

[mivey]

I agree with Rob & Dennis. I think the EC is getting his story mixed up or he drew the wrong conclusion about a particular incident.

 

[kwired]

Too many fans on a controller is ususally harder on the controller than the fans.

 

[normbac]

i put three on a patio with one switch 2 years ago no complaints if using a fan switch check watt allowance on switch legs the switch can burn up, tried remote, receivers all on same frequency with one control but the problem is that when turning one off, the other goes on etc pain in the ##$#@ for the owner but it does work just need to be exact when pointing remote.

 

[Jraef]

I'd be curious to know how could this have anything to do with premature fan failure?

Maybe he wired them in series? Don't laugh, I've seen it, although it was by a DIY guy, not an EC.

More likely he didn't pay attention to the switch rating, maybe looking at the Amp load alone. You have to look at the HP rating of the switch and add up all of the fans from a HP standpoint, converting Watts to HP if that's all they give you.

For example: a typical 15A rated toggle switch is rated for 1/2HP max. A basic residential ceiling fan is usually under 100W, but can be that high. If it is, 3 of them is 300W, which is .4HP, no problem. But if the EC had installed 300W industrial or commercial fans, then that's 900W. At first glance it's only 7-1/2A on a 15A switch, but that 900W is also 1.2HP and the switch will start to burn up when switching on and off. Over time, the switch damage causes a voltage drop, the fans overload and if they have a thermal cutout, they trip off. If not, they fail quicker.

Just do the math properly.

 

[readydave8]

Is it true that it's better to start a fan on high speed? So if a fan is controlled by a standard wall switch, and the pullchain on the fan is pulled to low speed, turning it on at the wall switch will shorten life of fan? Or is this another electrician's myth?

 

[Dennis Alwon]

Is it true that it's better to start a fan on high speed? So if a fan is controlled by a standard wall switch, and the pullchain on the fan is pulled to low speed, turning it on at the wall switch will shorten life of fan? Or is this another electrician's myth?

I don't believe that however, if you look at the variable fan rheostats they always start at high speed first just the opposite of a dimmer. Where the speed is set as a fan with individual speeds to select, I don't think it matters.

 

[Tom C]

I have had the same fan in the family room for about 20 years all winter it is set on low and controlled by wall s/w. Did have to oil it this year to get it turning.