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Help Replacing Combined Light and Extractor Fan Pull Cord

Postby heljb » Thu Aug 27, 2015 3:22 pm

Help please I need to replace the bathroom pull cord switch which also switches the exhaust fan. I thought I had purchased the correct switch but the old wiring is confusing me. So the photo shows the old wiring it has two ports marked 'L' the back ones and two marked 'N'.

The switch I have bought is a 2 way switch with the typical 'L1, L2, COM' ports. So what do I put where? You will see in the photo there is a small piece of red wire that goes from one port to another but isn't coming from the ceiling, this is mainly what is throwing me off. All help appreciated. Thanks
photo(1).JPG
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Postby ericmark » Thu Aug 27, 2015 11:28 pm

Likely you can put the linked wire to com and combine the black with red tape and red on it's own together and fit in either L1 or L2 does not matter which leaving other one empty.

But it really depends if there is another switch? The rules say with a non opening window you must be able to switch on fan without the light. The two pole switch you have will allow a push switch to be used as well as the light switch if wired that way sorry need to get correct switch.
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Postby heljb » Fri Aug 28, 2015 12:17 pm

ok so the black and red wire that was in 'N' and the single red that was in 'L' should go in the 'L1' and the other red wire that was in 'N' with a link to 'L' should go in the 'COM'? Have i read that correctly?
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Postby ericmark » Sat Aug 29, 2015 8:58 am

As said likely that will do it. However it does depend on if there is a second switch for fan. I can't test your wires I can only guess what is likely.

I think it's Part F building regulations which gives the rules for extractor fans. Where there is no requirement for a fan or where there is no natural light you can run the fan from the light switch only.

However where the fan is required by building regulations i.e. no opening window and you have natural light then you need a switch to operate the fan without using the lights. However in real terms that means no one switches it on. Using a double pole switch is a standard way around the rules. It can be wired so either the stand alone switch or the light switch works the fan.

Unless a double pole light switch is used then switching on fan will also switch on lights.
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Postby Bajaffern » Sat Dec 07, 2019 3:24 pm

How do identify a double pole switch?
I just replaced my pull cord switch that switches on the fan and the extractor fan together. The fan has a timer that switches off after 3 minutes of the light being switched off.
After replacing the switch, i noticed that when the light is switched on, the fan starts up but its very slow and hardly rotating but as soon as the light is switched off, the fan rotates faster (normal). My guess is that its probably due to the new switch not having enough amps to rotate the fan when the light is on.
The old switch said MAX16A and the one I purchased is 6A (One way)
Do i need to find a 16A switch and does it need to be double pole?
Or is there something else Im missing?
The wiring on the new switch is done exactly the same way as it was on the old one.
Brown and red wire in COM port and yellow/green and blue wire in L1.
Thanks
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Postby Mr White » Sat Dec 07, 2019 9:55 pm

The Amp rating of a switch is how much current (Amps) the switch can safely control.

Please post a picture of what you have actually done.
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Postby ericmark » Sun Dec 08, 2019 12:48 am

[quote="Bajaffern"]How do identify a double pole switch?
I just replaced my pull cord switch that switches on the fan and the extractor fan together. The fan has a timer that switches off after 3 minutes of the light being switched off.
After replacing the switch, i noticed that when the light is switched on, the fan starts up but its very slow and hardly rotating but as soon as the light is switched off, the fan rotates faster (normal). My guess is that its probably due to the new switch not having enough amps to rotate the fan when the light is on.
The old switch said MAX16A and the one I purchased is 6A (One way)
Do i need to find a 16A switch and does it need to be double pole?
Or is there something else Im missing?
The wiring on the new switch is done exactly the same way as it was on the old one.
Brown and red wire in COM port and yellow/green and blue wire in L1.
Thanks[/quote]
You really should not hijack a 4 year old post, you should have started a new one.

However it is not normal to connect a yellow/green to anything but earth, I would suspect it was not wired that way to start with.
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