bathroom extractor fans

[junglistmatty]

I have a really annoying double light switch for my bathroom light, which is really strange; I've never seen this before....

One switch controls the light,
The second switch is for the extractor fan and the fan will only turn on when the light is on, after the light is turned off, the fan will remain on for roughly 10mins. During the fan timer, it doesn't matter if you flick this switch, it doesn't do anything. The same applies when the fan and light are both turned off; flicking the fan switch doesn't do anything.


NOTE: There is also a fan isolator switch above the bathroom door.


Anyone seen this sort of thing before? I really would like to replace it with a single light switch, I'm thinking I may need a double pole switch or would a simple two way do the job? I've not yet taken the switch off the wall to check the wiring going into the switch.

 

[Taylortwocities]

I've not yet taken the switch off the wall to check the wiring going into the switch.

There are lots of ways of wiring this sort of thing up. How to reconfigure will depend on what you have there.

CAREFULLY take the switches off the wall (turn power off first) and then post a picture on here.

Here's how to post a photo //www.diynot.com/forums/viewtopic.php?t=129539

 

[ban-all-sheds]

I really would like to replace it with a single light switch

If you do that the fan will come on every time you turn on the lights, and carry on running until about 10 minutes after you turn them off.

Will that be OK?

 

[ban-all-sheds]

Here's how to post a photo //www.diynot.com/forums/viewtopic.php?t=129539[/QUOTE]
Matty - when you go there, please follow the link How to upload photos - you have to do all 11 steps.

If you use an iPhone to take the photos you may need to fix the orientation before you upload them http://www.google.co.uk/search?q=iphone+image+orientation

 

[junglistmatty]

I really would like to replace it with a single light switch

If you do that the fan will come on every time you turn on the lights, and carry on running until about 10 minutes after you turn them off.

Will that be OK?

Yes, that's fine as there is a fan isolator switch just above the door (the downstairs loo has the same but with a single light switch); this switch will shut off the fan or stop it coming on in the first place.

Thanks,

 

[ban-all-sheds]

So you'll still be using two switches to control the fan.

Except they won't be next to each other and one will be over the doorway.

 

[JohnW2]

So you'll still be using two switches to control the fan. Except they won't be next to each other and one will be over the doorway.

Indeed, but if I understand what is being said, the isolator (over the door) probably would not be used routinely. I think that (as is the usual situation when there is a fan isolator) it would normally be on, but could be used to prevent the fan coming on (with lights) if/when that was ever required. However, maybe I've misunderstood.

Kind Regards, John

 

[EFLImpudence]

That's what is there now.

 

[JohnW2]

That's what is there now.

Not quite. At present there are two switches (one for light and the other for fan) and also the 'fan isolator' above the door.

The present fan switch (as opposed to isolator) must be interrupting the S/L feed (from the adjacent light switch) to the fan, since we are told that switching it off during the timed run-on period does not cause the fan to go off (and that it cannot trigger the fan if the light is off). That is an arrangement I've never seen (have you?), and AFAICS the only point of it would be to enable one to prevent the fan being triggered by the light switch, if one wanted that functionality to be available. If the OP doesn't (want that functionality), then if he simply got rid of that switch (joining the wires currently going to it, or taking the S/L feed to the fan directly from the light switch) he would then have the 'usual' situation with a light switch and fan isolator. However, whether that's what he wants, I don't know for sure.

Kind Regards, John

 

[EFLImpudence]

The present fan switch (as opposed to isolator) must be interrupting the S/L feed (from the adjacent light switch) to the fan, since we are told that switching it off during the timed run-on period does not cause the fan to go off (and that it cannot trigger the fan if the light is off). That is an arrangement I've never seen (have you?),

Yes, I think that is the logical way for those who don't want the fan on at night when just cleaning teeth or peeing.

When the fan switch is left on it works 'normally' with the light.

 

[JohnW2]

The present fan switch (as opposed to isolator) must be interrupting the S/L feed (from the adjacent light switch) to the fan, since we are told that switching it off during the timed run-on period does not cause the fan to go off (and that it cannot trigger the fan if the light is off). That is an arrangement I've never seen (have you?),

Yes, I think that is the logical way for those who don't want the fan on at night when just cleaning teeth or peeing. When the fan switch is left on it works 'normally' with the light.

Yes, I suppose that makes sense - although, as I've said, I don't recall having seen such an arrangement. I suppose the main problems are (a) in finding the fan switch to operate it night before one switches the light on and (b) remembering to put the switch back into the 'on' position (again, if one can find it!) after switching the lights off at night.

I therefore wonder what the OP actually wants. If he wants the functionality you've described, he's got it. If he doesn't, he can either ignore the fan switch (leaving it permanently 'on') or remove it in the manner I described, leaving him with the 'usual' arrangement for a timer fan.

Kind Regards, John

 

[ban-all-sheds]

I would have thought that if you wanted to stop the fan from working as routinely as using the room for washing your hands, cleaning your teeth, or having a pee (unless after eating asparagus), then using an isolator above the door would be a PITA, and that the way the OP has it now would be much better.

 

[JohnW2]

I would have thought that if you wanted to stop the fan from working as routinely as using the room for washing your hands, cleaning your teeth, or having a pee (unless after eating asparagus), then using an isolator above the door would be a PITA, and that the way the OP has it now would be much better.

If it's going to be a 'routine' happening, then I would agree. I don't think we've really established what the OP wants to end up with it, or how 'routinely' he would want to disable the fan. However, I do think that if one frequently disables the fan, either with his existing switch or the isolator, switching it back on will often be forgotten, undermining the concept of a light-triggered fan ... so maybe he should be thinking of humidistat or water flow triggering (I won't suggest PIR!).

Kind Regards, John

 

[ban-all-sheds]

True, we don't know how often.

But this:

Yes, that's fine as there is a fan isolator switch just above the door (the downstairs loo has the same but with a single light switch); this switch will shut off the fan or stop it coming on in the first place.

leaves me, at least, in no doubt that it's more often than when the fan requires isolation for maintenance purposes.

 

[junglistmatty]

Hi guys, interesting read there

What I want is a single light switch by the bathroom door, and that this light switch will also turn on the fan any time I turn on the light.

It's for a downstairs toilet under the stairs right outside the kitchen/living room. The extractor fan's isolator switch (above the door) is switched off most of the time as we hardly ever require the fan as the toilet isn't used for anything other than having a quick pee (because of it's location in the house).

Therefore, it's suitable for us to only have one switch as the other switch doesn't really do anything (because the isolator has switched the fan off anyway). It's really annoying when you hit the wrong switch going into the toilet in a rush and the light doesn't come on.

Thanks