Using a dimmer switch for bathroom light, with a fan.

[HappyHippyDad]

My customer would like a dimmer switch for the bathroom lights. The light switch also switches on the fan.

They are not worried that the fan will not work if the dimmer switch is switched on when on low. However, I wanted to get some opinions on whether there is any realistic danger involved?

Thanks.

 

[westward10]

The fan motor could over heat.

 

[HappyHippyDad]

The fan motor could over heat.

Thanks westward.
Is that because of the increased current?

 

[brianmoooore]

Does the fan have an over run timer?

 

[HappyHippyDad]

Does the fan have an over run timer?

Yes...
I'm trying to fathom your thinking, but cant.
Perhaps you're thinking its safe(r) because the lower voltage is only being used to switch the fan on, and then the PL (at 230V) keeps the fan going?
I 'think' that's how a timer fan works.

 

[mickegh]

Not sure if fan would operate safely but I would split them

 

[westward10]

If it is a run over fan then the dimmer will not affect the permanent live.

 

[brianmoooore]

If it is a run over fan then the dimmer will not affect the permanent live.

Conversely, if it wasn't an over run fan, then I'd expect the fan to be damaged by the dimmer if (when?) it stalls at low dimmer settings.
With an over run fan, I'd expect the fan too work normally, except possibly at low dimmer settings, when the pulses from the dimmer may not be enough to trigger the timer.

 

[Pretty Mouth]

With an over run fan, I'd expect the fan too work normally, except possibly at low dimmer settings, when the pulses from the dimmer may not be enough to trigger the timer.

That was my experience of wiring an overrun fan through a dimmer. With the SL dimmed down low, it took about a minute for the fan to wake up.