150mm timed extractor fan not working with timer function (photos of wiring)

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Vedb

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Hello all!

I've got a peculiar issue whereby the wiring of an extractor fan seems to be wrong (but working) however it doesn't allow for the timer function to work off the permanent live. Please take a look at the photos to show you the inputs, the wires and also the only configuration which allows the fan to come on with the switch. I'm confused as to why the inputs don't match in the conventional way and also why the permanent live won't keep the fan on after switching off the light. Any advice?

Much appreciated!
 
That's just it, the usual colouration doesn't apply here and I don't know why it was wired this way. However the only combination which works is the one I've shown on the photo, otherwise the fan doesn't power on.

You can see what they're labeled as on the fan so the assumption is that the wires then correspond to these with black being live, brown timer and grey neutral. I've tried them every which way to see if I can get it right but it always comes back to this.
 
An update,

It also works in this configuration. Which I've copied from the fan in the bathroom. However it also does not stay on when the light is switched off.

1000123717.jpg
 
you need to do some actual testing of the cables coming in to see which cable does what. winging it and randomly trying different combinations will either not work, or do damage and not work
 
Thank you. There's only so many combinations it can be so I wanted to do this without having to call someone in, who also may not be able to do it.

I've not had to test wires before, can someone recommend good gear for testing?
 
simple voltage tester will do

there is only so many combinations, however get them wrong, and chances are you've damaged the PCB so matter if you do then get the right combination afterwards, the damage is already done
 
Unfortunately there is no defined standard of which colours to use.

If there is a fan isolator switch have a look inside that, they are often labelled and that might give you a clue.
 
who also may not be able to do it.

Very unlikely they would not be able to do it!

An electrician with proper test would have identified the wires and confirmed if the fan timer itself is faulty or not probably quicker than it took you to post the question & photos.. 10mins work.

If it used to work, (from the photos it doesn't look like its a new fan?), and has now stopped working.. Then most likely its the timer circuit board that has failed....
As there would be no logical reason to assume the wiring was wrong..

I'm not sure how robust that timer PCB is..?
But as Andy said it is never a good idea to just randomly swap 230v wiring connections around when trying to get something working..
 
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