Bathroom extract isolator

[Firehanger]

Hey peeps,

I have a movement sensor in my en suite which turns on the extract fan. Trouble is, it's been installed so that it only triggers the fan when the light switch is on.

I want to rewire it so that the fan comes on irrespective of whether the light is on or off (but obviously still controlled overall by the isolator switch).

I've added pictures of the back of the isolator switch and light switch, but cannot get to the movement sensor as its a spring mounted flush design and I can't work out how to remove it from the wall without damaging the plasterboard.

In order to rewire it for the above configuration, will I need to gain access to the movement sensor, or should it be a case of rewiring either the light or isolator switch?

I've got a multimeter, and have had a go figuring out the circuitry by checking the continuity of various wires, but to no avail.

Can anyone suggest how I can go about this please? I'm at a loss!

Thanks

Chris

 

[littlespark]

On the fan isolator, one of the3 cores goes to the fan, but where does the other 3 core come from?

The terminals on the sensor have to be accessible somehow. Send a photo of that and someone might know how to remove the cover without damaging the decor

 

[suffolkspark]

I would "guess" one of the browns in the top terminal of that switch just needs movibg in with the others in the bottom, one will likely go to the sensor and the other to the light so try one at a time.... Be sure to follow safe isolation procedures each time

 

[littlespark]

You won’t get 4 wires into one terminal on an MK switch. Go into a connector first, then single brown into terminal.

Mark every cable before disconnecting. 5 browns, it’ll be easy to lose track

 

[Michael Sands]

If you could test at isolator to make sure you have permanent live plus a switched live and not two switched lives but a look at terminations at fan would help because a lot op people mess that up just as much as the the switch and isolator
Also it’s refreshing to see proper cable identification at switches

 

[Wilko]

... In order to rewire it for the above configuration, will I need to gain access to the movement sensor, or should it be a case of rewiring either the light or isolator switch?
Can anyone suggest how I can go about this please?

His Chris and welcome to the Forum.
I start by drawing out the circuit, both as it is now and what you want it to be. Post them up here and we'll comment. Spelling and Neatness will likely get comments too, sorry in advance .

 

[Wilko]

Perhaps a JW video might get you started :

 

[buzzlightyear]

dont pratt about with it, get a spark in.

 

[Firehanger]

You won’t get 4 wires into one terminal on an MK switch. Go into a connector first, then single brown into terminal.

Mark every cable before disconnecting. 5 browns, it’ll be easy to lose track

Thanks, sound advice. Problem is I don't know what wires need to go to what terminals to make it work the way I want to. Annoyingly, when it was first installed it was configured the correct way, but it annoyed me that the fan would come on in the middle of the night if we used the bathroom, so I asked him to switch it so it only worked when the light came on. What I'd forgotten was that this bathroom has windows, unlike our others, so I actually need the fan to work with the light off, e.g. During the lighter months.

Any suggestions for how to resolve which wires I need to got to which terminals to do that?

 

[buzzlightyear]

Any suggestions for how to resolve which wires I need to got to which terminals to do that?

fishmonger ,that wire
configuration is beyond you .do you self a faver get some body in.

 

[Firehanger]

fishmonger ,that wire
configuration is beyond you .do you self a faver get some body in.

Lol, I hear ya. Just don't wanna pay a call out fee for 5 mins work is all....

 

[buzzlightyear]

how do you know its 5 mins to do that ?and a call out .it is not fault .but alterations.

 

[Midwest]

Lol, I hear ya. Just don't wanna pay a call out fee for 5 mins work is all....

On another forum I've given some advice, but ultimately said get in an electrician. Forum rules do not allow a step by step by guide, and its starting to go that way Firehanger. That 5min job would take up an hour of someone's time.

Do you not know of someone who can recommend you an electrician, apart from the one you don't want to use again?

 

[Firehanger]

On another forum I've given some advice, but ultimately said get in an electrician. Forum rules do not allow a step by step by guide, and its starting to go that way Firehanger. That 5min job would take up an hour of someone's time.

Do you not know of someone who can recommend you an electrician, apart from the one you don't want to use again?

Ah, fair play. I didn't realise that. Soz.
Will have a think and see who I can get in then!
Cheers all

 

[Dunc N]

You need a permanent live to the sensor and a switched live to the fan. Not sure if the fan you have can do this. No detail.