Bathroom fan control.

[Benway]

I'm part way through a bathroom upgrade and I'm installing a fan. The Fan will come on with the lights. I'd also like to have control over the fan independently of the light.

I'd like to be able to turn the fan off while the lights are on if I'm using the bath, I'd also like to be able to turn the fan on while the lights are off to clear any steam after the shower has been used.

Is this possible using 2 way switching? I've had a quick think about it but it's been a long day and my brain melted.

L/S F/S Light Fan
ON ON ON ON
ON OFF ON OFF
OFF ON OFF ON
OFF OFF OFF OFF

L/s Light Switch
F?S Fan Switch

Cheers

 

[OwainDIYer]

Use 2 single-way switches and treat the fan as a second, independent, light

//www.diynot.com/wiki/electrics:lighting:lighting_circuit_layouts

 

[Benway]

The fan wouldn't come on automatically with the light though would it?

Cheers.

 

[ban-all-sheds]

You have quite clearly said that you don't want it to come on automatically with the light....

 

[PrenticeBoyofDerry]

Why don't you use the standard set up of overrun/timer fan with a 3 pole isolator switch.
This would allow overrun when light is off to clear humidity and also isolation of fan when you would like to have light on but fan not.
This of course will require the light to be used to allow for overrun but you could also consider humidistat fan, that will function when humidity is high, regardless of light operation.

//www.diynot.com/wiki/electrics:lighting:fan
timed fans
humidistat

 

[ericmark]

You may be able to buy 2 pole 2 way grid switched which then would allow a second two way switch to also work the fan but you could easy have the fan switched on when some one leaves the bathroom and switches off the light so just can't see how it would work!

The standard pneumatic timed push switch would likely be best option and have no connection with the lights.

 

[Scoby_Beasley]

Flow switch in the shower/boiler cold feed?

 

[bernardgreen]

Use a two gang two way switch

One gang controls the light
Common to Live , L1 to Switched Live to lamp

Second gang controls fan

Common to the fan's Switched Live
L1 to the L1 on the first gang ( switched live to the lamp )
L2 to Live

Fan's Llive to Permanent Live

In one position of gang 2 the fan follows the lamp and it the other position it stays on.

 

[EFLImpudence]

L/S F/S Light Fan
ON ON ON ON
ON OFF ON OFF
OFF ON OFF ON
OFF OFF OFF OFF

L/s Light Switch
F?S Fan Switch

Isn't that just being switched independently.

I realise you said you wanted the fan to come on with the lights - but you don't.
Even if you did that - every time you left the room you would have to switch the fan to the next required method.
So you had just as well switch on the fan when you want it to run.

 

[17thman]

You have quite clearly said that you don't want it to come on automatically with the light....

He quite clearly said that he did.

 

[EFLImpudence]

You have quite clearly said that you don't want it to come on automatically with the light....

He quite clearly said that he did.

He quite clearly said that he did but then went on to describe a number of scenarios when he did not.

So, sometimes he does, if the person, at the last visit, left the switch(es) in the correct position.

 

[17thman]

You have quite clearly said that you don't want it to come on automatically with the light....

He quite clearly said that he did.

He quite clearly said that he did but then went on to describe a number of scenarios when he did not.

So, sometimes he does, if the person, at the last visit, left the switch(es) in the correct position.

"The fan will come on with the light" is what he said.

sounds automatic to me. there maybe variables to include. Prentice boy gave the ideal solution.

 

[EFLImpudence]

Agreed.

However -

The Fan will come on with the lights.

I'd like to be able to turn the fan off while the lights are on

I'd also like to be able to turn the fan on while the lights are off

 

[Simon35]

Flow switch in the shower/boiler cold feed?

Exactly what I've done in mine...works a treat, £40 for the flowswitch, fan with built-in timed overrun.

I did think about adding a humidistat in parallel with the flowswitch, still might.

 

[Benway]

Heh, maybe I should have been a little more clear....

I was after the fan coming on with the light, and then having further control after.

Either way, cheers for the answers.