Wiring in a an extractor fan (toilet)

[dinger541]

Hi folks,

Just need a wee bit of help here!
Im about to put an extractor fan in the toilet/ shower room and before you shout i know about all the roolz, ive been a good boy and planned it..... but i have a small dilema. I dont want the extractor fan to be on all the time, only when the shower is on ( and with the help of the timer after the shower has finished) but i have a prob with selecting which power to take the FCu and fan off of. Either the original light (and it'll go on with the light) or off the power to the shower (which is already FCU'd by pull switch) i have the facility to place the FCU outside the room so thats ok. the only other way i can think is independant power via FCU and seperate pull switch inside or light/fan switch outside.....either of which will be an eyesore but safe.........ALWAYS WITH THE SAFETY...yes i know breezer i have listened..... And ive drawn a diagram.... in fact several.

any sugestions will be gratefully received.......... as usual

Thanx

Dinger

 

[breezer]

...yes i know breezer i have listened..... And ive drawn a diagram.... in fact several.

any sugestions will be gratefully received.......... as usual

Thanx

Dinger

if you take the feed off the lights no FCU required (isolation switch yes)

 

[dinger541]

Breezer

As usual, succinct and to the point....thanx m8

Been away for a while, jus getting back to doing the house so expect more questions in due time.

Thanx again

Dinger

 

[securespark]

I knew it was a toilet when you said you needed a "wee bit of help".....

I'll get my coat...

 

[securespark]

Breezer

Some fan manufacturers do ask for fuse even if taken off lighting. Crazy, I know, but there you are.

 

[ban-all-sheds]

The fact that you say the shower circuit has an FCU must mean it's a powered shower pump, rather than an electric shower. If the total load of the fan and the shower is too great for the fuse value specified for either item, then regrettably you'll need to either ignore the product advice, or have the switch before the bank of 3 FCUs that you'll need (2 for the fan, 1 for the shower pump) - bit of a cr@ppy solution, or fit a second switch.

But then you just know, don't you, that people will either forget to turn the fan on, or forget to turn it off.

Powering it from the lighting circuit would be better in some ways, but then it'll come on when it often isn't needed.

2 other possibilities.

1) You could use a DP switch for the shower pump & fan to switch the fan live and the pump live simultaneously but independently. Depending on fusing requirements you might still need separate FCUs, but only two of them, and if you use switched ones, and put them before the DP pullswitch they would also provide the all-pole isolation function for each appliance.

2) You could use an IPx5 rated PIR in the ceiling over the shower to switch the fan.

Piece of ****, really...

Anyway, flushed with my success at coming up with some ideas I'll take a seat now.

Hope it pans out alright for you, and that sorting it doesn't drive you round the bend.

And even though I'm on a roll, I'll put a lid on the jokes.

 

[dinger541]

Well,

I didnt realise you could put so many loo jokes in one answer boys....thanx for that....

I'll go away and look at the prob and the possible solutions and i'll tell you wot ive decided later...

Thanx again for the help ..much appreciated

Dinger.

p.s. The jokes were ****.........****....get it???...... i'll get my coat

 

[securespark]

Ban. Surely there's an easier answer?

Wire the timer fan as normal through a triple pole iso, triggered via the room light(s).

If you want the fan on with the lighting just pull light switch. If you want lights on without the fan, just switch the triple pole iso. off.

Work?

 

[ban-all-sheds]

He doesn't want it triggered by the lights, he wants it triggered by the shower, and that means that there may be fusing issues.

 

[breezer]

Well,

I didnt realise you could put so many loo jokes in one answer boys....

are you taking the P***?

(no, its another loo joke)

 

[nstreet]

Why not use a humidty triggered fan. Shower on - lots of humidity, shower off - fan runs until humidity normal again. See here, another 'beastly' fan from Plumbworld http://www.plumbworld.co.uk/666-10145

 

[ban-all-sheds]

I've always wondered how well those work - woudn't you already have got condensation on the walls by the time they kick in?

 

[nstreet]

I think you will always suffer from some condensation, especially if you have tiled floors and walls, unless the fan as an extremely high extract rate.

In which case your ears will probably pop due to the depressurisation.

 

[securespark]

In my experience, they work OK