Wiring a bathroom extractor fan.

[Unklian]

Hi There.

My new bathroom steams up and I'm considering fitting / having an extractor fan fitted. I can do most of the fitting myself but would like to have final wiring done properly by an electrician.

There is easy access in the loft for wiring a timed extractor to the lighting circuit.

There is no easy access to ring mains for the main power.

There is access in the loft for taking the power from the feed to the shower.

I assume the extra 15w on top of a 9.8Kw shower would be no problem.

Could the electrician take the feed from the shower power?

Any suggestions advice please before I start / abandon the idea?

Cheers.

Ian.

EDIT:- Or can I simply use the lighting circuit alone and a pull cord?
Or, is it possible that in the lighting circuit there will be a permanent AND a switched live that he could use?

 

[holmslaw]

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[Unklian]

Not really wanting to cut into my new suspended ceiling......

I've been in the loft and had a look round......

Currently at the top of the stairs is a 2 gang switch.
One switch is the upstairs landing light......also switched from downstairs.
The 2nd switch is for the bathroom light.

If I could run a cable down alongside the existing wires,
could I install a 3 gang switch with a simple link wire from the bathroom light supply to the 3rd switch, then from there, up to the extractor fan?

This would mean that I could have the fan running in the summer
when I don't have the lights on in the bathroom.

Good / Bad idea?

Cheers.

Ian.

 

[ban-all-sheds]

You could post a photo, or a description, of the wires at the switch but your idea probably won't work as there's probably no neutral there.

You can have the fan triggered by the shower circuit, either as I did mine: //www.diynot.com/forums/viewtopic.php?t=20386, or by swapping the shower switch to the lighting circuit and using it to do the fan and a contactor for the shower (simpler than my system, but I didn't think of it at the time ), or by having the fan triggered by a flowswitch in the water supply to the shower.

Or, of course, a humidistat fan which will come on when required.

You should also think about where you'd like the fan isolator switch to go.

 

[Unklian]

Current switch is a 2 gang.
1st switch is the landing switch also switched from downstairs.

The 2nd switch......Just a switched live to the bathroom lights......I was hoping to take a link from the permanent live side of this to......

New 3rd switch......The switched live from this, I would run up the wall alongside the existing wires to the extractor fan.

The fan Neutral,......I was going to use a Neutral from the lighting ring above the bathroom. It currently has a junction box which powers 4 GU10 lights.

The 3 gang switch would then be......
1) Landing light.
2) Bathroom light.
3) Bathroom extractor fan.

I was going to use twin & earth cable with redundant conductors cut back and insulated.

Or......If I can find some, single core, double insulated cable.

Thanks for the help up to now.

Ian.

 

[holmslaw]

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[ban-all-sheds]

Care to provide a cogent and rational explanation as to why?

 

[holmslaw]

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[londonboy]

Care to provide a cogent and rational explanation as to why?

If you don't have an opening window then it contravenes Building Regulations.

 

[ban-all-sheds]

There is an opening window, but even if it didn't why would it contravene the BRs?

As for the contactor coil, I did look into that at the time and I couldn't find any requirement to protect the actual coil in its own right.

 

[holmslaw]

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[ban-all-sheds]

Thats not a solution it's a cock up.

Not according to Schneider, who say that it's not necessary to protect the coil with a fuse.