timmed bathroom extractor fan

[paulcarter]

Hi

I am fitting a timed extractor fan and would like it to come on with the light. There are down lights and we only have access to the last light on the circuit. It is going in the loft space so we can put all switches up there. We can get to the lighting ring for other rooms but not to the switch cable for the bathroom. Any one know what we can do please

 

[EFLImpudence]

Assuming a normal wiring arrangement, you will have to access the light connections which connect to the supply and the switch otherwise you cannot do as you wish.

This will normally be at one of the lights (original position) but could be in a junction box anywhere.
It may be at the switch but this is not likely.

Why do you not have access if the fan is going in the loft? Boarded?

You will have Switched live and Neutral and hopefully Earth at the 'last light' meaning a Permanent live will have to be brought from another point on the same circuit.

 

[paulcarter]

Assuming a normal wiring arrangement, you will have to access the light connections which connect to the supply and the switch otherwise you cannot do as you wish.

This will normally be at one of the lights (original position) but could be in a junction box anywhere.
It may be at the switch but this is not likely.

Why do you not have access if the fan is going in the loft? Boarded?

You will have Switched live and Neutral and hopefully Earth at the 'last light' meaning a Permanent live will have to be brought from another point on the same circuit.

It is all boarded and we can't get to the junction box, we can only get to the lighting circuit that goes above the bathroom next door. The light was the last 1 one the loop of 5 down lighters. If we can't do it this way what will be the best way to do it.

 

[EFLImpudence]

I'm unsure exactly what the situation is.

If you wire the fan from the 'last light' the fan will operate with the lights (as long as they are 240V) but the timer won't work.

Can you not access the supply by removing the appropriate light and feed a 3core+e cable between the joists to the fan (do they run the right way?).

 

[sparkwright]

As said above, the normal way is to fish a cable under the floorboards or whatever the obstruction is.

It will be the permanent live you are missing; you should get the switched live, neutral and earth from that last light fitting.

Though not the most orthodox way, I see no reason why you can't obtain the permanent live from another point of the SAME lighting circuit.

6241y cable is good for this.