Bathroom extractor fan only works when light is off! (pictures and video included)

[seasickstevie]

I have noticed that your isolator switch looks like it has a metal face in the photos. If so, you need to connect the earth wires into the earth connection on the switch face. The screw is missing, but you may be able to use a screw from one of the unused connections of the switch.

Good point from huggybear, particularly associated with the bathroom wiring.

However I don't see a chance of there being an unused spare screw, as all six terminals are in use.

 

[nescafe37]

I have just wired in a fan same as the OP and I'm having the same issue. The only difference is that my grey wire is blue sleeved which indicates neutral doesn't it?

 

[Taylortwocities]

Sleeved in blue should mean neutral, assuming it’s actually connected to neutral.

What does your two probe voltage tester tell you?

 

[nescafe37]

Was getting 240v between grey and black with switch on. 240v between grey and brown all the time.?

 

[nescafe37]

I also wired in the fan exactly the same as the one I took out although the original fan wasn't working either lol...

 

[ericmark]

You need to start a new thread, 2020 is a bit old, and also any answers are not only aimed at @nescafe37 but also @jonnythedent although not seen since Oct 2021.

It does seem with @nescafe37 grey is neutral, brown permanent line, and black switched line, but I would wonder about if a true neutral, or being grounded by something. These were so good to test with as they actually used some power, but you need to find the other end of the triple and earth and see what it is connected to.