Power for extractor fan

Dec 07, 2004 11 Replies

Hi, I've bought a extractor fan which I'm installing in the bathroom. It's going to have its own on/off switch (pull cord). The instructions say that it should be installed via a 3amp FCU. On the specs, under Power, it says 20W.



To my mind this would mean it's acceptable to power it from a spur off the upstairs lighting circuit, which currently has the 4 first floor room lights and a couple of flourescent tubes in the loft. Am I correct in this assumption?



A spur off the ring main would be a bit of a pain as I have already taken a spur off the nearest handy socket for the power shower, and using other sockets in the area would probably involve lifting floorboards etc, so I'm keen to avoid this if possible.



Thanks for any advice. Andy


You can get special fan isolaters for this - they are often three pole.

Yes they are often wired from lighting circuits. This is also because many fans have the option of being triggered by the light switch. They have a permenent live and a switched live (hence the three pole switch). This allows for operations like "run on" (where it keeps running for a few mins after you turn the switch off).

"AndyP" wrote | I've bought a extractor fan which I'm installing in the bathroom. | It's going to have its own on/off switch (pull cord). | The instructions say that it should be installed via a 3amp FCU. | On the specs, under Power, it says 20W. | To my mind this would mean it's acceptable to power it from a spur | off the upstairs lighting circuit, which currently has the 4 first | floor room lights and a couple of flourescent tubes in the loft. | Am I correct in this assumption?

Yes. And whilst it would be irresponsible of me to urge you to ignore the manufacturer's instructions, if I was putting it in my own house I'd ignore the requirement for the FCU - if the lighting circuit is MCB'd at 6A.

Owain

You really should have a dedicated circuit for a power shower.

Why? Assuming it's a power shower, and not an electrically-heated shower? David

On Tue, 7 Dec 2004 11:05:59 +0000 (UTC), "AndyP" strung together this:

Yes, powering the fan from the lighting circuit is fine, I do it that way 99% of the time.

On Tue, 7 Dec 2004 15:18:40 -0000, "Phil Jones" strung together this:

No you shouldn't. It might be advisable if possible but not required.

It's a power shower, not an electric shower - the instructions stated that it could be powered from a spur off a ring main, via a 3amp FCU. Andy

I am fitting a similar one - wiring to the lighting circuit - decided to fit a 3 Amp FCU even though it does not really need it - that way everything is to the manufacturers instructions etc. By the way - I originally was going to get the fan and vent kit from one of the local sheds - but the outer vent there was white and did not match the brickwork. Made a good saving at a local electrical merchants - got a branded fan better than the "no -name" one at the sheds and a brown vent grill & FCU and pattress all a few pounds cheaper than just the fan kit at the sheds - worth shopping around.

Dave

it can be, doesnt mean it has to be done that way

NT

On 7 Dec 2004 15:06:15 -0800, snipped-for-privacy@meeow.co.uk strung together this:

What?

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