bathroom extractor fan

[gavin.sibley]

Hello all,

Just a quick one, I think I know the answer anyway but it's one of those I'm doubting myself haha

I wired up a extractor fan In a customers bathroom, taking a feed from the light via a 3 pole isolator and onto the fan.

The fan went faulty so I went back to test and power was still getting to the fan on both live and switched love conductors, and all connections were right, so told customer it was a faulty fan.

At this point we introduce the plumber, who supplied the fan In the first place.

He is now saying that the fan has bed wired up wrong and isn't allowed to be wired in this way.

Just wondering if anyone can tell me whether this is right or wrong, as I said I think I know what's coming but he's making me doubt myself.

Cheers,
Gavin

 

[SJD]

I installed a couple of Xpelair fans earlier this week, instead of requiring the usual 3A fuse, the instructions said "the protective fuse for the appliance must not exceed 5A". I think there are one or two other brands that don't need 3A, but can't recall them.

 

[dazza1981]

OTT in my opinion..... you would hope under normal circumstances there's a 6 amp protective device for the lighting circuit you have supplied the fan from which would probably trip way before the fan causes a fire hazard

 

[SJD]

That's my point, Xpelair are almost saying just that - with a 5A fused lighting circuit, you're covered, with a 6A MCB lighting circuit then technically no but in practice yes?

 

[dazza1981]

So you still got to install a fcu anyway!!!! wnkers

 

[MDJ]

At the end of the day you read the instructions with the fan, if it calls for a 3 amp fuse then legally you may have trouble if one isn't fitted, in reality it is rarely carried out haha

 

[davethsparky]

was that aimed at moi?

Nope, twas aimed at post #26

 

[dazza1981]

I have always put a fcu in if the instructions say so just to cover my aris but as sjd says,if they state the fuse must not exceed 5 amp and you on a 6 amp mcb then its just more of an annoyance...... why not just make the integral wiring of the fan able to withstand say...........6 AMPS!!!!! LOL

 

[EastAnglian]

if they state the fuse must not exceed 5 amp and you on a 6 amp mcb then its just more of an annoyance..

If you feel its a justifiable exception to BS7671 then simply record it as such (with your reasoning) on the MWC or EIC.

 

[decolad69]

How long can fanny go on .........

 

[Geoffsd]

And where on earth did you learn that? I don't see anything in this thread to suggest that.

Not sure to what this refers.

I did say that if the fuse operates but is connected in such a way that the fan remains live despite the operation of the fuse then it may lead to the false assumption that the fan is not live.

I don't see the difference between this and other situations where appliances contain more than one line but which will be isolated by one switch or indeed a landing light switch which contains two separate circuits.
Would someone assume the fan is not live when it just packs up without blowing a fuse?

As you say a fuse is there to protect the cable, which of course raises the question of how it can be acceptable for the fuse to leave part of the cable live if it is there to protect the cable when all of the conductors in the circuit are part of the same circuit?

Protection against overload does not necessarily ensure isolation - as above.
Test for dead.

And of course you have missed the point of the discussion which is concerned with the use of said fuse to protect the equipment not the cable.

I have not missed the point - one of the live conductors is not associated with any overload which may occur.

Please do take the time to read the posts and understand the things you have read before posting unhelpful sarcastic comments.

You seem to disapprove of sarcasm but not patronisation.

 

[decolad69]

Not sure to what this refers.


I don't see the difference between this and other situations where appliances contain more than one line but which will be isolated by one switch or indeed a landing light switch which contains two separate circuits.
Would someone assume the fan is not live when it just packs up without blowing a fuse?


Protection against overload does not necessarily ensure isolation - as above.
Test for dead.


I have not missed the point - one of the live conductors is not associated with any overload which may occur.


You seem to disapprove of sarcasm but not patronisation.

Fanny by gas light ....... it's easier .