Wiring Problem in Bathroom Ask questions and find answers to many subjects relating to electrics and electrical work

[notasparky]

I have decided to simply remove an existing bathroom light and fit a new light in its place. There is no new or additional wiring involved just changing the light fitting itself. However, I have taken down the old light and revealed wiring that I don't fully understand. I now have bare wires hanging from the ceiling and a new light to fit without knowing which goes where. I have taken photos if it helps but here is the set-up - I just hope somebody can please help me so I can put the new light up.

1. I have 2 sets of what appear to be red and black.
2. I have 1 set of what appears to be 3 red and 1 black.
3. I have 1 green (earth) wire.

The set-up in the bathroom is:
Dual light switch outside the bathroom wall which operates the landing light, the bathroom light and the extractor fan which comes on when I turn on the bathroom light.

Any help would be appreciated.

[IMG]http://i429.photobucket.com/albums/qq12/notasparky/STA60045.jpg[/IMG]
[IMG]http://i429.photobucket.com/albums/qq12/notasparky/STA60047.jpg[/IMG]
[IMG]http://i429.photobucket.com/albums/qq12/notasparky/STA60048.jpg[/IMG][/img]

PS Forgot to mention that there is also a switch in the entrance hallway for the landing which obviously doesn't work now....

[ericmark]

You are lucky correct colours used.
All earth's have been put together with one single sleeve on them all.
The cable with two red wires goes to the switch and at the lamp end one red goes to new lamp and the other goes with all the other red wires.
I think of the remaining cables:-
1) Is main feed
2) Is feed to next lamp
3) Is feed to fan
But also you may have no feed to next lamp and two wires both go to fan one feed at all times and one feed only when lamp is on.
If two wires go to fan then connecting all blacks together and all but one of pair of reds together (The odd one goes to lamp) will cause the fan to run at all the time. If this is the case one of the group of three reds needs to go with the red going to lamp instead. As to which one unless you noted it when you removed old rose then trial and error. Or meters out and ring out cables.
So on completion you will have 4 connections.
Earth
Loop
Neutral
Feed to lamp
So you will need a 4 way junction block not the 2 way shown in picture.
Eric

[notasparky]

[quote="ericmark"]You are lucky correct colours used.
All earth's have been put together with one single sleeve on them all.
The cable with two red wires goes to the switch and at the lamp end one red goes to new lamp and the other goes with all the other red wires.
I think of the remaining cables:-
1) Is main feed
2) Is feed to next lamp
3) Is feed to fan
But also you may have no feed to next lamp and two wires both go to fan one feed at all times and one feed only when lamp is on.
If two wires go to fan then connecting all blacks together and all but one of pair of reds together (The odd one goes to lamp) will cause the fan to run at all the time. If this is the case one of the group of three reds needs to go with the red going to lamp instead. As to which one unless you noted it when you removed old rose then trial and error. Or meters out and ring out cables.
So on completion you will have 4 connections.
Earth
Loop
Neutral
Feed to lamp
So you will need a 4 way junction block not the 2 way shown in picture.
Eric[/quote]


Hi ericmark

I had hoped that you would pick this up as you always appear to be very helpful and knowledgeable.

I will give it a go shortly - of course soon to be in darkness as I need to isolate the mains (don't trust pulling fuses as none are marked up).

Hopefully this will work with trial and error - any pitfalls to watch out for - don't want to blow fuses or me for that matter???

Regards

[notasparky]

[quote="ericmark"]You are lucky correct colours used.
All earth's have been put together with one single sleeve on them all.
The cable with two red wires goes to the switch and at the lamp end one red goes to new lamp and the other goes with all the other red wires.
I think of the remaining cables:-
1) Is main feed
2) Is feed to next lamp
3) Is feed to fan
But also you may have no feed to next lamp and two wires both go to fan one feed at all times and one feed only when lamp is on.
If two wires go to fan then connecting all blacks together and all but one of pair of reds together (The odd one goes to lamp) will cause the fan to run at all the time. If this is the case one of the group of three reds needs to go with the red going to lamp instead. As to which one unless you noted it when you removed old rose then trial and error. Or meters out and ring out cables.
So on completion you will have 4 connections.
Earth
Loop
Neutral
Feed to lamp
So you will need a 4 way junction block not the 2 way shown in picture.
Eric[/quote]


Hi - Thanks for taking the time to respond. As you may have guessed, I am a complete novice so I think it will be trial and error and best in daylight tomorrow morning.

Are there any DANGEROUS pitfalls (of course I will switch off the mains before I start) but want to avoid blowing fuses etc. when switching back on. The main problem being that I do not know which cables run to which items i.e which go to the fan etc.

I have two single blocks spare that I will incorporate to make a 4 block as you suggest....

[ericmark]

If you don't feel you are able to do the work then get someone in to do it not worth taking chances and I have that feeling you may have to do it in the end anyway if your going to get fan working correct.
Eric