Bathroom extractor fans

[jcsteve]

Having low voltage downlights in a new bathroom which had to be shower rated has made me think I ought to check on what the rules are for extractor fans......can anyone help answer a couple of qs?

1. What is the rating required for zone 2 (>2.3m above shower)?

2. I need to install an isolating switch outside the bathroom......what sort and where should it be sited?

3. How powerful would it need to be? room is 2.5 X 1.5

4. Anything else I need to know?

NB This will be inspected by proper electrician for building regs approval.

thanks....

 

[RF Lighting]

1. What is the rating required for zone 2 (>2.3m above shower)?

Zone 2 requires electrical products to be IPX4 or better, or SELV with the transformer located in zone 3 or beyond

2. I need to install an isolating switch outside the bathroom......what sort and where should it be sited?

You should install a three pole fan isolator switch like this. This should be installed outside the bathroom and be readily accesible. The normal mounting place is above the bathroom door, with the fan transformer mounted adjacent.

3. How powerful would it need to be? room is 2.5 X 1.5

Depends how high your ceiling is

4. Anything else I need to know?

Don't know, but feel free to ask more questions

 

[ebee]

RF, Does SELV exclude the need for IPX4 in zone 1 or 2 ?

 

[jcsteve]

thanks for the info.....ceiling is 2.4m

also....do you normally run them off the lighting circuit?

I was plannning to use one with a humidistat so doesn't need to be triggered by the light.

 

[RF Lighting]

RF, Does SELV exclude the need for IPX4 in zone 1 or 2 ?

Not entirely sure, but it does read like that. I lifted the quote from here (the bottom section of the page)

 

[securespark]

See here:

 

[ebee]

I`m afraid that drawing is wrong although it`s been repeated al over the place (I wonder where it originated) it shows the Lavatory Hand Basin as influencing the zone boundaries yet the regs & guides do not.
The use of SELV does not preclude the use of IPX4 in zones 1 & 2 in fact guidance note 1 contains a table 8.1 simplifying it

 

[jcsteve]

Thanks for the info guys.....one further question.....are there any similar rules for kitchen or utility room extractors?

Kitchen has typical over the cooker hood couple of metres from the sink.

Utility is a small windowless room with w/m, drier and sink.

thanks.

 

[ban-all-sheds]

3. How powerful would it need to be? room is 2.5 X 1.5

Put it this way - unless it's so powerful that you cannot close the bathroom door while it's running, and pets and small children are lifted from their feet, you can't really have one that's too big...

 

[Job_n_knock]

A 4" fan would be fit for purpose.

 

[ban-all-sheds]

6" would be even fitter.

Manrose do a neat SELV one, with a variety of transformer options (plain, timed, humidistat etc),