Bathroom extractor fan-to switch live or not to switch live.

[Drible79]

Hi,

I am currently considering replacing my bathroom extractor with one of the humidistat ones. However, my question is this...

I currently have to switch the light on every time I want the extractor to come on but in the summer/during the day when light is pouring in through the window I don't want the light on I just want the extractor on.

The extractor has a three pole isolator switch which is above the door frame (outside).

Do I have to have it working through the light switch or can it be wired to run straight from the isolator given the humidistat will control the on/off function of the fan when it needs too?

Thanks.

 

[EFLImpudence]

Yes, you can do what you want.

It will need to have the wiring reconfigured...

but does the humidistat not already work the fan when the light is off?

 

[Drible79]

I haven't actually bought it yet. The one I have is just a timer one. I've never used one of the humidistat ones before. Does it require two permanent lives instead to work independently from the light?

 

[ban-all-sheds]

I imagine it just requires the one. It switches itself on when it detects the need.

 

[Drible79]

The instructions (as such) on the web site state that it needs the standard three but there must be a way of installing one without it being dependant on the light being on.

 

[ban-all-sheds]

Is there a wiring diagram?

 

[Drible79]

No, not on the site. I will wait for the unit to arrive and then check. Worst case I'll have to continue with the light on but its a waste of leky given todays climate!

 

[EFLImpudence]

The instructions (as such) on the web site state that it needs the standard three but there must be a way of installing one without it being dependant on the light being on.

There is.

You can have it dependent on the humidistat alone and/or -

from its own separate (from light) switch and/or -

it may have a pull-chord to turn it on permanently or off permanently (not both) when you want.