Problem with bathroom fan wired through light

[tom foster]

I have been swapping over a bathroom light fitting for a new one. It has a fan wired through it, which was done by the previous owners. I took a photo of the wiring before starting, and replicated the wiring in the new fitting. However, when I switch the light on now, the fan doesn't come on. Then, when I turn the light off, the fan comes on briefly. I'm wondering if it has got out of sync somehow, and if there's a way of resetting it?!

Here's a picture of the wiring - I don't know if it looks correct or not to an expert eye. The white wires on either side go to the light fitting.

Any advice would be appreciated![/img]

 

[EFLImpudence]

Firstly, well done for taking a picture before you started.

All I can say is that you have not replicated the wiring correctly and to check again.

There should also be four CPCs (earths) sleeved green+yellow and connected to the earth terminal.

 

[AndyPRK]

Where's the before pic?

Isn't there a black wire missing?

 

[EFLImpudence]

Ah. I missed that.

I thought that was the before picture.

 

[tom foster]

Yes, that is the before picture - it looks exactly the same now as I just re-used the plastic covered wiring block. There are no earth wires present - as I said, this was installed by a previous owner of the house. It worked fine previously, which is why I don't understand why it's not working now!

 

[Taylortwocities]

There are no earth wires present -

Well, there jolly well should be!

Although, that is not the answer to your problem!

However. There does not seem to be any copperat the end of that black wire (maybe its the camera angle) and as Andy says, there should be another black wire somewhere.
EDIT: Post a pic of the wiring how it is now.

 

[plugwash]

Here's a picture of the wiring - I don't know if it looks correct or not to an expert eye.

A few things I notice

1: No earths are visible. Of course they may be in a terminal block hidden behind the fitting.
2: You seem to be a black wire short. Given the red/blue/yellow cable to the fan and the fact you have a total of four red wires i'd have expected to see three black wires.

Can you get access from above? if you can it may be easier to see what is going on from there.

 

[tom foster]

Thanks for the helpful replies. There is copper at the end of that wire, it's just the camera angle!

It's interesting that there seems to be a black wire missing. There are definitely only two present. I can't get access from above, as it's located below an overhanging tiled porch roof (it's in a downstairs bathroom).

 

[Lectrician]

I can't see a pic...

 

[Taylortwocities]

Looks like he deleted it from his album

 

[tom foster]

No, I didn't delete it - don't know why it's disappeared. I have re-uploaded it here:

 

[plugwash]

The next thing I would do is take the fitting off and see if you can find out if the wires are part of cables and if there are hidden earths (and if so what has been done with them).

 

[leezer3]

Before taking the fitting off, try with a non-energy saving bulb and see if your results differ.

 

[pompeygit]

Strange like said before seems 1 black to few or 1 red too many. Really needs a tester on it to determine the function of each wire. 10 minute job if you've got the gear

 

[AndyPRK]

a few more pics wouldn't go a miss. before, after different angle.

or pulled down showing the grey/white cable covering