Extractor Fan and Switch

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alexpuk2002

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Hi,

Looking for a bit of help regarding my extractor fan which was wired up recently. It all works but it works in a way that doesn't turn the fan on when turning the light switch on. If I turn on the Isolator switch for the fan above the door then the fan works, whether the light is on or off. To turn the fan off I have to turn the isolator fan off.

I was wondering if this could be changed to work when the light switch is turned on and then turns off when the light switch is turned off. I'll outline below how the wiring is connected from what I can see in the loft and when taking the isolator switch off the wall.

From the isolator switch there are 3 wires. There is a 4 core (think thats the right term - it has brown, grey, earth and black wire) which goes to the fan in the loft, a 3 core cable going to the light switch and another 3 core cable which goes into a junction box. Coming out of the junction box is another 3 core cable which goes to one of the spotlights. I have taken a photo from the loft of the wires, but it won't let me upload it from a file on here.

Any advice would be great.

Thanks,

Alex
 
No 1, whoever "wired it up recently" get them back, they have wired it wrong.

Otherwise post pictures of the wiring inside the light switch, the fan isolator switch and the fan itself.
 
looks like too many browns in the one terminal, I would guess that the black is the switch line from the spot lights

the cable from the switch is unneeded / or connected in the wrong terminal,
 
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looks like too many browns in the one terminal, I would guess that the black is the switch line from the spot lights
I think the black is from the extractor fan. Think it is the 4 core cable that has the grey, black brown and earth which connects the isolator switch to the fan
 
I think the black is from the extractor fan. Think it is the 4 core cable that has the grey, black brown and earth which connects the isolator switch to the fan
if that is the case, then there should be a brown cable in with it,
but there seems to a total mess-up of the wiring , you will need to start again
 
if that is the case, then there should be a brown cable in with it,
but there seems to a total mess-up of the wiring , you will need to start again
Yeah I thought I might need to start again, just not sure where to start with it or how it's supposed to be wired up.
 
So at the isolator, only ONE, the black actually passes through one pole of the switch (it is a 3 pole switch)

Assuming the convention of brown = permanent L. Grey = N and Black = switched L, then the fan will indeed only be controlled by the fan isolator switch.

Call the installer back and tell him to do it properly.

All 3 of the cores going to the fan should pass through the 3 pole switch. I am not convinces you actually have a switched live (one that turns on with the light) going into that isolator switch?
 
So at the isolator, only ONE, the black actually passes through one pole of the switch (it is a 3 pole switch)

Assuming the convention of brown = permanent L. Grey = N and Black = switched L, then the fan will indeed only be controlled by the fan isolator switch.

Call the installer back and tell him to do it properly.

All 3 of the cores going to the fan should pass through the 3 pole switch. I am not convinces you actually have a switched live (one that turns on with the light) going into that isolator switch?
Maybe not. I have done a bit of research about how to wire up an extractor fan and it looks like you have the 3 core and earth cable (the one that has black and grey cables) coming from the fan connected into the top of the isolator fan, another 3 core and earth cable connected to the bottom of the isolator fan going to the spotlights.

The thing that I am wondering about is why there is a cable coming from the switch that turns on the spotlights and wall lights connected to the isolator fan.
 
The person who wired that up is an incompetent idjut in my opinion...

Obviously they didn't test it?
Did you get any minor works electrical certificate for this alteration?

You are now caught between the devil & the deep-blue-sea... where...

(a) they should come back and put it right free of charge...
(b) but if they couldn't get it right first time I personally wouldn't want them back!
(c) getting a proper electrician who knows what they are doing to rectify this bodge-up will cost you more money..

Was this by any chance installed by a "bathroom fitting company"...
Who can do everything.. plumbing / electrics / tiling etc...?

Or as is generally known... "Jack of all trades & master of none!"?

A fan isolator has three poles switched:- permanent live (in/out), switched live (in/out), neutral (in/out).
Which requires SIX terminals to be used! Your photo only has THREE in use... Never Ever Going To Work!!!

The actual colours used can be dependant upon the personal preferences of who did the work..
Providing suitable cable sleeve is used any colour could be used for any function...
(excluding the bare CPC, earth conductor that must only be used a earth, not a live conductor!)

Are you sure they have fitted a timer fan?
 
The person who wired that up is an incompetent idjut in my opinion...

Obviously they didn't test it?
Did you get any minor works electrical certificate for this alteration?

You are now caught between the devil & the deep-blue-sea... where...

(a) they should come back and put it right free of charge...
(b) but if they couldn't get it right first time I personally wouldn't want them back!
(c) getting a proper electrician who knows what they are doing to rectify this bodge-up will cost you more money..

Was this by any chance installed by a "bathroom fitting company"...
Who can do everything.. plumbing / electrics / tiling etc...?

Or as is generally known... "Jack of all trades & master of none!"?

A fan isolator has three poles switched:- permanent live (in/out), switched live (in/out), neutral (in/out).
Which requires SIX terminals to be used! Your photo only has THREE in use... Never Ever Going To Work!!!

The actual colours used can be dependant upon the personal preferences of who did the work..
Providing suitable cable sleeve is used any colour could be used for any function...
(excluding the bare CPC, earth conductor that must only be used a earth, not a live conductor!)

Are you sure they have fitted a timer fan?
It was fitted by an electrical company. We were moving the bathroom upstairs and this room used to be a bedroom so only had a light and plug sockets in there.

They can and fitted the wiring for the spotlights and the wall lights and the fan. Everything works just not the fan in the way it should work when turning the lights on and off.

The extractor fan is a Manrose SCF200TN that is fitted in the loft.

The house does need a rewire at some point so it will get sorted, but just wanted to know if there was a way to get this working properly without chasing out the walls and replacing cables really.
 
It was fitted by an electrical company. We were moving the bathroom upstairs and this room used to be a bedroom so only had a light and plug sockets in there.
I hope the removed the sockets ??
You should have a certificate for the electrical work carried out and it is notifiable to building control. If you don't have any of this I would either get them back to do a proper job or (ideally) get another competent person to come and check it out (if you don't know any look on Napit or NICEIC etc website to find one in your area). Bathrooms are classed as "special locations" due to the reduces electrical resistance of the human body when wet and thus require different considerations to a normal room. If they can't get an extractor fan right I personally would want to be satisfied that the rest of the work is safe.
good luck
 
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but just wanted to know if there was a way to get this working properly without chasing out the walls and replacing cables really.
I would say yes it is possible, but the guy that wired that up was no electrician, if you want it to work in the way it should then you will need to get an electrician.
 
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