Replacing bathroom extractor fan pull-cord switch

[chil]

I have an RDL 4 inch extractor fan in the ceiling of my bathroom. It was built into my house in 1995 when my house was erected. The problem I had was that although the pull cord always turned the fan on straight away, when it was pulled to turn it off, it often would not stop the fan. Sometimes it would take an hour of repeated pulling before the fan would stop. As a result, I decided to change the switch at the top of the pull cord. I bought a 2-way ceiling switch from Wilkinson, but cannot work out how to wire it in. There are too many wires to attach. 2 bundles of wires come down from the ceiling. The first has red, green/yellow and black wires; the other red, green/yellow, blue and yellow. My switch only has 4 screwing-in points, labeled L1, L2, Com and Earth. Can you please help me? I do not understand what the blue and yellow wires represent - they are not the pre-2004 colours for neutral, earth or live! I would put back the old switch but I cannot work out how to put it together again - it has lots of loose pieces. I have searched the internet but cannot find any useful guidance, and I do not want to short-circuit the house! Please help!

 

[sparkyspike]

It sounds like your fan has a built in run-on timer. It will be adjustable between a few seconds and about 10 minutes. This may be why it doesn't turn off. Every time you turn the light back on, the fan timer resets itself.

So you need to put the switch back on (or the new one if you've destroyed the old one).

Have a look inside the fan. This will show you which colour cable goes where. And you can also turn down the timer so it goes off quicker (it's a small potentiometer about 8mm across).

It's not possible to tell exactly how it is wired, as there is more than one possible way. The usual way would be: Both Reds to COM. Yellow to L1. Ignore L2. Black and Blue joined in a terminal block. All the green and yellos in the earth terminal.