Bathroom lighting and fan query...!!

[mgzr]

ok so any help would be greatly received..!

just finished a rewire on a bungalow...

the new owners of the property are planning to do the kitchen and bathroom in the summer, so i've reused the old shower and cooker supplies and kitchen ring and put them away in the new board for the time being...

the bathroom had an existing 2 gang switch on the outside (fed with a 3 core twin and earth) which separately switched the lighting and inline fan... fully aware there is no triple pole isolator for the fan, but will certainly be fitting one further down the line...

i rewired the feed to the bathroom, to an adaptable box (fitted with din rail) and connected the feed to the red core of the 3 core down to the switch and used the blue as the switch wire for the fan and yellow for the switch wire for the lights....

a fairly straight forward switching set up etc....

when the circuit is energised the lighting switches correctly on and off, but as soon as i switch on the fan, the lights go out..?!?

oh and the fan was fed with an existing 2 core twin and earth, so no permanent feed just a switch wire and neutral....

any ideas anyone..!!

thanks in advance....

 

[Octopus]

Without seeing it first hand it's not really possible to say. Did you do any dead tests before energizing?

 

[mgzr]

carried out r1+r2 and insulation resistance...
everything came back ok...!

the bathroom feed is an end of line....

come the summer, when the customer decides to rip the old bathroom out, i fully intend to install a fan isolator and will keep the light switch in the original place (hall side of the bathroom door) and fit a 1 gang purely for the lighting.

just seems bizarre......

thanks for the input..!!

 

[Leesparkykent]

ok so any help would be greatly received..!

just finished a rewire on a bungalow...

the new owners of the property are planning to do the kitchen and bathroom in the summer, so i've reused the old shower and cooker supplies and kitchen ring and put them away in the new board for the time being...

the bathroom had an existing 2 gang switch on the outside (fed with a 3 core twin and earth) which separately switched the lighting and inline fan... fully aware there is no triple pole isolator for the fan, but will certainly be fitting one further down the line...

i rewired the feed to the bathroom, to an adaptable box (fitted with din rail) and connected the feed to the red core of the 3 core down to the switch and used the blue as the switch wire for the fan and yellow for the switch wire for the lights....

a fairly straight forward switching set up etc....

when the circuit is energised the lighting switches correctly on and off, but as soon as i switch on the fan, the lights go out..?!?

oh and the fan was fed with an existing 2 core twin and earth, so no permanent feed just a switch wire and neutral....

any ideas anyone..!!

thanks in advance....

Have you got a photo of the connections in the switch and your connections you made in the adaptable box you can post up?

 

[mgzr]

unfortunately not....

the feed to the switch (red core) is linked out across the 2 commons of the 2 gang switch...
and the switch wires (blue and yellow) are connected to the out going lives (in the adaptable box) for the lighting and fan respectively....

i'm pretty dam sure the connections are correct...

 

[westward10]

Where does the live feed at the two gang switch go to first, the light side or the fan side.

 

[mgzr]

the fan side and linked across to the light side...

 

[Midwest]

Have you got live & neutrals mixed up somehow, switching on the fan presents 230v at the lights neutral? Just a thought.

 

[mgzr]

initially thought something very similar, however i checked my connections and everything was ok...

the neutral connection at my adaptable box, contains the neutral in, and both the neutral for the lights and neutral for the fan....

 

[Midwest]

Back to basics then, and check wiring & connections. Perhaps draw out your design, make sure your not making a mistake. Can only think it's something simple?

 

[mgzr]

the yellow switch wire (for the lighting) remains live when i throw the switch for the fan....

but lights go out...?!?! so initially i also thought perhaps it was loosing its neutral somewhere...

 

[mgzr]

crude wiring diagram.....
but this is an 'as fitted' drawing...

View attachment 35540

(CPC emitted for clarity)

View attachment 35541

 

[Des 56]

Remote possibility and clutching at straws but we are all capable of silly things on occasion
Is it possible that you have assumed each gang is oriented as you believe and one of them is the other way

 

[mgzr]

so you're saying potentially the live feed goes into one of the switches on the common and links across to the other switch on the 'L1' terminal...?!

shouldn't make a difference......?!?!

 

[westward10]

It is odd the light turns on with one switch but goes off when the fan is switched especially when you have a solid link at the live feed.

 

[mgzr]

out of interest, i doubled up both switch wires (blue and yellow) on one switch, and re engergised the circuit. this time around, the lights didn't work at all but the fan operated with the switch....

 

[Des 56]

so you're saying potentially the live feed goes into one of the switches on the common and links across to the other switch on the 'L1' terminal...?!

shouldn't make a difference......?!?!

No,if you have your link in L2 instead of off the feed in the common , you have a simple changeover
I was just suggesting that silly mistakes can and do occur,it seems to me this thread almost definitely suggests a changeover and there is only one place that is going to occur

 

[Wilko]

If the wiring was as per dwg then there wouldn't be this problem, I think.

 

[mgzr]

i can see your thinking....

however, i can throw the light switch and the yellow become live (230v - and lights come on) then throw the fan switch and the blue becomes live and fan starts up but yellow switch wire remains live but lights go out......

 

[westward10]

If the wiring was as per dwg then there wouldn't be this problem, I think.

This is what I don't understand the live feed is solid between the switches and as long as one is in common and the other L1 or L2 the other switch should have no affect on it. Effect or affect, I never know

 

[Wilko]

Ha ha, my fav is :

A is different from B
Or
A is different to B

Good thing I can add up ok

 

[Midwest]

Still think somehow, you are introducing a voltage at the lights neutral, when turning on the fan. Think you just need to check all your connections are correct.

 

[westward10]

Connect them to the same switch and see what happens.

 

[buzzlightyear]

to an adaptable box (fitted with din rail

loop in from the switchs is better .

 

[mgzr]

Connect them to the same switch and see what happens.

i have double up both switch wires and the fan turns on and off with the switch, but the lighting does nothing....

 

[Wilko]

Guessing from afar, what should be the light neutral is actually connected to the incoming unswitched live.

 

[Richard Burns]

If your connections are correctly positioned then the only thing I can think is to check is that neutral connections on the DIN rail are correctly connected, if one (probably the incoming) were only just in contact then it may not be able to carry the current of both items, however this would be an extraordinarily precise partial disconnection.
I woudl tend to go for a wiring error myself, check continuity when the circuit is dead to see what you get in different switch positions and see if you have continuity along cores between points.