bathroom extractor fan always running

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chamsters
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bathroom extractor fan always running

Post by chamsters » Fri Oct 20, 2017 4:29 pm

Hi there,

I've been having an issue with my bathroom extractor fan - quite sure I know what the issue is but thought I'd check with you good folks before electrocuting myself!

To sum up:
* Fan always runs, whether lights are on or off
* Definitely a switched fan - there's a live and a switched live input for wiring, both are connected
* There's a LED power light on fan. It goes off after a while when the lights are off, but fan continues to operate. When i switch lights on, the LED turns back on

My guess here is that the live and the switched live are swapped. Would that make sense and result in above behavior?

Happy to take photos as required!

Thanks
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someone-else
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Re: bathroom extractor fan always running

Post by someone-else » Fri Oct 20, 2017 4:33 pm

More information is required.

Has the fan recently been changed?
Has any wiring recently been changed?
Is this a brand new installation?

Anything else you would like to tell us?
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Re: bathroom extractor fan always running

Post by chamsters » Fri Oct 20, 2017 4:35 pm

someone-else wrote:More information is required.

Has the fan recently been changed?
Has any wiring recently been changed?
Is this a brand new installation?

Anything else you would like to tell us?
Moved into this place 6 months ago. Fan doesn't look new. No idea of history re: changed wiring.
Identical fan in another bathroom works as intended - stays on for 5-10 mins after you switch off lights, then turns off. This one just remains on.
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Re: bathroom extractor fan always running

Post by wine~o » Fri Oct 20, 2017 4:36 pm

I'd hazard a guess that you are correct. Lecky off and swap live/permanent live.

If that doesn't work then the timing circuit has probably failed... not normally a replaceable part so time for a replacement fan.

(could also be a humidity stat failure, but you don't mention a humidistat)
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Re: bathroom extractor fan always running

Post by chamsters » Fri Oct 20, 2017 4:38 pm

wine~o wrote:I'd hazard a guess that you are correct. Lecky off and swap live/permanent live.

If that doesn't work then the timing circuit has probably failed... not normally a replaceable part so time for a replacement fan.

(could also be a humidity stat failure, but you don't mention a humidistat)
what's worst that could happen if i swap permi live + switched live? Fan just wouldn't turn on right?
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Re: bathroom extractor fan always running

Post by someone-else » Fri Oct 20, 2017 4:42 pm

I am thinking the timer has given up, but swapping Live and switched live will do no harm.
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Fret not, a forum is a collection of opinions. Above, are mine.

Which is correct? Metre or Meter? Click the link to find out more.

Working on anything electrical? have you got a multi meter? why not? Would you hit a nail with a shoe?

If gloom had a voice, it would be me. :mrgreen:

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Re: bathroom extractor fan always running

Post by wine~o » Fri Oct 20, 2017 5:40 pm

chamsters wrote:
wine~o wrote:I'd hazard a guess that you are correct. Lecky off and swap live/permanent live.

If that doesn't work then the timing circuit has probably failed... not normally a replaceable part so time for a replacement fan.

(could also be a humidity stat failure, but you don't mention a humidistat)
what's worst that could happen if i swap permi live + switched live? Fan just wouldn't turn on right?
exactly. or the fan would still constantly run as it already does.
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Re: bathroom extractor fan always running

Post by OnlyMe » Fri Oct 20, 2017 6:04 pm

someone-else wrote:I am thinking the timer has given up, but swapping Live and switched live will do no harm.
Doing that should make the fan act a non timed fan ie it will only switch on with the lights (works with 99% of timed fans).

So unless the wiring to the fan is incorrect, that should prove that the timer is faulty.
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Re: bathroom extractor fan always running

Post by OnlyMe » Fri Oct 20, 2017 6:10 pm

wine~o wrote:(could also be a humidity stat failure, but you don't mention a humidistat)
Very possible. Or an incorrectly set stat.
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Re: bathroom extractor fan always running

Post by multiman » Sat Oct 21, 2017 8:00 am

A model may help if you can see a humidistat will have a small sensor on board to sense air levels and have an adjustable screw or knob on it normally with a + - on there.

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Re: bathroom extractor fan always running

Post by Morbius » Sun Oct 22, 2017 9:49 am

Surely the fan has been running fine up till now, have the wires magically swapped over on their own? I would say it is either a faulty pcb causing the timer fault, or the timer needs turning down, or the fan has a humidistat and that needs turning up.
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Re: bathroom extractor fan always running

Post by chamsters » Sun Oct 22, 2017 9:52 am

Hi folks,

OK so there was no impact turning up the timer. Could not find humidistat. Ended up getting replacement fan on amazon for £15, installed last night and it works great with same wiring set up.

So - was definitely an issue somewhere on the old fan, likely a shot timer.

Thanks for the help!
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Re: bathroom extractor fan always running

Post by multiman » Sun Oct 22, 2017 9:54 am

Great glad all sorted

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