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HappyHippyDad

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Evening all....

My son is 14, he seems to be taking ultra long baths and showers and the bath/shower room is drenched afterwards.

I have just bought a pretty good inline fan and was planning on fitting it on its own switch as the existing lights are on a dimmer. I would love the fan to come on with the lights so that it is guaranteed it comes on when he is bathing.

Is there any way of doing this on a dimmer? The dimmer will be staying as it's too bright at night when on full.

I thought I could install a standard plate switch which switches power to both the fan and the dimmer switch. in other words the dimmer switch doesn't get power unless the fan is on. However, this is too cumbersome. Is there any way the fan can work with a dimmer switch?

A few more questions..

What actually happens to a fan if you install it on a dimmer switch? I'm guessing it would work fine if the dimmer is on full, but problems occur if the dimmer is lowered? Would this be dangerous or would the fan just cease to work as it doesn't have the required voltage?
 
Evening all....

My son is 14, he seems to be taking ultra long baths and showers and the bath/shower room is drenched afterwards.

I have just bought a pretty good inline fan and was planning on fitting it on its own switch as the existing lights are on a dimmer. I would love the fan to come on with the lights so that it is guaranteed it comes on when he is bathing.

Is there any way of doing this on a dimmer? The dimmer will be staying as it's too bright at night when on full.

I thought I could install a standard plate switch which switches power to both the fan and the dimmer switch. in other words the dimmer switch doesn't get power unless the fan is on. However, this is too cumbersome. Is there any way the fan can work with a dimmer switch?

A few more questions..

What actually happens to a fan if you install it on a dimmer switch? I'm guessing it would work fine if the dimmer is on full, but problems occur if the dimmer is lowered? Would this be dangerous or would the fan just cease to work as it doesn't have the required voltage?
Could you put a motion sensor in . Then it would work any time you enter the bathroom
 
I thought I could install a standard plate switch which switches power to both the fan and the dimmer switch. in other words the dimmer switch doesn't get power unless the fan is on. However, this is too cumbersome.
You can obtain single plate switches with a rotary dimmer and a rocker switch side by side, with independent connections, so that is a viable method - is it cumbersome because of having two 'knobs'? Or is it because of having to add/re-route cables?
Is there any way the fan can work with a dimmer switch?
What actually happens to a fan if you install it on a dimmer switch? I'm guessing it would work fine if the dimmer is on full, but problems occur if the dimmer is lowered? Would this be dangerous or would the fan just cease to work as it doesn't have the required voltage?

Edit - assuming it's a timed overrun fan, the dimmed connection will act as the trigger for the fan to come on, but surely the motor will be powered from permanent live, so will either work properly, or not come on at all? I suspect the dimmed feed to the fan might trigger it more or less at any setting?
 
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Yes, it can be done, but the dimmer module will need modification.

I initially tried to do this using the dimmed switch live from the dimmer to the SL of the fan. It sort of worked, but the fan took ages to be triggered, about a minute or more IIRC. Back to the drawing board.

The modification to the was easy enough to do, and worked perfectly. John Ward has a video on how to do it on old leading edge module, but the way I did it on a V-pro module was less faff. I'll PM you details.
 
Could you not use a current detector switch on the light, that switches the fan, through a timer relay?
Sounds expensive though..
 
Haven't fitted a dimmer switch since the rise of cfls and now LEDs, so a bit out of touch with what's on the market, but if your dimmer has a physical mechanical on/off switch incorporated into it's design, and is dismantlable, you should be able to solder a fly lead onto the switch output, before it feeds the dimmer.
Wouldn't be acceptable for a customer, but if it's for your own house...
 
Really appreciate all the answers, thanks all.

Umming and arghing between PM's idea of playing with the V-Pro or just putting in a sensor.
 
Yes, it can be done, but the dimmer module will need modification.

I initially tried to do this using the dimmed switch live from the dimmer to the SL of the fan. It sort of worked, but the fan took ages to be triggered, about a minute or more IIRC. Back to the drawing board.

The modification to the was easy enough to do, and worked perfectly. John Ward has a video on how to do it on old leading edge module, but the way I did it on a V-pro module was less faff. I'll PM you details.
I'd be very interested in this 'hack' too...
 
As mentioned by someone else above - just fit a humidistat fan and let the embedded controller do the hassle for you! Probably end up cheaper, too.
 
Yes, it can be done, but the dimmer module will need modification.

I initially tried to do this using the dimmed switch live from the dimmer to the SL of the fan. It sort of worked, but the fan took ages to be triggered, about a minute or more IIRC. Back to the drawing board.

The modification to the was easy enough to do, and worked perfectly. John Ward has a video on how to do it on old leading edge module, but the way I did it on a V-pro module was less faff. I'll PM you details.
Yes, it can be done, but the dimmer module will need modification.

I initially tried to do this using the dimmed switch live from the dimmer to the SL of the fan. It sort of worked, but the fan took ages to be triggered, about a minute or more IIRC. Back to the drawing board.

The modification to the was easy enough to do, and worked perfectly. John Ward has a video on how to do it on old leading edge module, but the way I did it on a V-pro module was less faff. I'll PM you details.
Hi can you please pm me how to do this with a v pro dimmer to control a vent axia inline fan. Thanks
 
Hi, I have a similar issue in that I want to be able to dim the lights but make sure teh fan comes on. It is a timer fan so I assume it has its own power supply as it runs for a while after the light goes off. The switch is a pull cord one. I was wondering if something like this would work as it monitors a traditional switch input. I would then set the dimmer intensity in the software. Quinetic 1 Amp WiFi Mini Wireless Switch/Dimmer Receiver | Quinetic (QURWM1) - https://www.tlc-direct.co.uk/Products/QURWM1.html
 
Hi, I have a similar issue in that I want to be able to dim the lights but make sure teh fan comes on. It is a timer fan so I assume it has its own power supply as it runs for a while after the light goes off. The switch is a pull cord one. I was wondering if something like this would work as it monitors a traditional switch input. I would then set the dimmer intensity in the software. Quinetic 1 Amp WiFi Mini Wireless Switch/Dimmer Receiver | Quinetic (QURWM1) - https://www.tlc-direct.co.uk/Products/QURWM1.html
You mean put it in the lighting circuit at the light (so not affecting the existing wiring to the fan)?
Yes I think that will work. The receiver needs neutral and permanent live as well as the feed from the switch - worth checking those are present at the light fitting (with a traditional ceiling rose arrangement they should be, otherwise you will need to get permanent L there)
 
Update....

I have fitted the fan. It works just fine with the dimmer. As long as the lights are are least half full strength when you initially switch it on then the fan comes on. You can then dim the lights as much as you want as the PL keeps the fan going.

I guess if you dimmed them below half, the fan would switch off after the overrun, but the boy always has the lights full on and I only dim them that low when I need a quick visit to the loo in the night. In fact, it works perfectly as I don't want the fan to come on in the middle of the night.

I probably wouldn't suggest it to a customer though.
 
Much simpler method is to change the light switch to a rocker and install bulbs you can dim from your phone (wifi) or a remote. This is what I had to do in a basement gym that didn't have a switch live to the fan, and they wanted to work-out with mood lighting.
 

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