Shower Room Extractor Fans

[Thomas]

Hello

Planning on installing an extractor fan in the en-suite to reduce condensation - currently looking at:

about how to activate/deactivate the fan. Options seem to be:

(1) dedicated on/off switch (2) wired to light circuit with 2 min delay (3) wired to light circuit with in-line isolator switch

I tend to favour (3) since it allows the light to be on without the fan - good for those occasions when lighting only is needed. What are the regs concerning switches, fuses etc?

Also wondering about best place to install - currently favouring ceiling mount near door rather than directly above shower cubicle.

Any comments?

Thanks Thomas

[Owain]

I fyou mount near the door you will have a 'short circuit' of air from the door to the fan, you really need the airflow to cross the room and for condensatione xtracting above the shower or close to it would be best.

Owain

[geraldthehamster]

at:

> Wondering about how to activate/deactivate the fan. Options seem to be: >

Why not get one with an inbuilt humidistat, that comes on when it detects a certain level of humidity, and turns itself off?

cheers Richard

[newshound]

at:

>>> Wondering about how to activate/deactivate the fan. Options seem to be: >>

That's best, but I find one just wired in parallel with the shower light is OK (single pull cord for light + fan). Best to extract from inside the cubicle, though.

[YAPH]

BES does 100mm humidistat fans cheap

[Jules Richardson]

Are they reliable? As in, does the humidistat bit last as long as the fan?

[rbel]

About to have a shower extract fan fitted. I have gone for an in-line Soler & Palau TD160

is exceptionally quiet and moves a reasonable volume of air at its low power setting. The extract grille is being sited directly over the shower enclosure. I was thinking of a separate (Vent-Axia) humidistat with a discreet pull cord over-ride given the cost I am considering a pre-set timer switch such as

[Toby]

> Wondering about how to activate/deactivate the fan. Options seem to be: >

You have to install an isolator switch for it, these are generally installed outside the bathroom - If you have a fan that has a built in timer and is activated by the lights, then you need a three pole isolator like this

will switch Neutral, permanent and switched live.

With this, you can simply install a timed fan (an/or a humidistat) and turn this switch off when you just want lights and no fan, for the midnight relief.

If the fan is just a simple fan without a timer, or their PIR model (assuming this doesn't need a connection to the light switch as well as a permanent supply) and you want intendant control, then you just need a normal switched fuse spur like this

fan instructions will specify what fuse rating it requires, if that matches what your lighting circuit is protected with, then you won't need to install an extra fused spur like this if you choose the timed type with a fan isolator switch.

[Thomas]

Thanks for the very useful replies

Thomas

[Thomas]

Many Thanks Thomas

[David WE Roberts]

Going down much the same route (TD250) but I think I will pay up for the Vent-Axia humidistat. Had one before and liked it. Will probably get a run on timer - could get the fan with timer but I suspect that changing the delay time will require access to the fan body - the one in the loft is fine but the one in the ceiling downstairs may be more of an issue.

Cheers

Dave R

[rbel]

I have had a chat with the sparks about the humidistat and he mentioned that they can be prone to switching on when the shower is not in use but the bathroom temperature falls/humidity increases when the CH switches off or goes to night set back. Have you any experience of this? I see that Vent-Axia now do a 'stat which can cope with this problem

[David WE Roberts]

Interesting - the looks like an alternative to the one I found on the Vent-Axia site a few days back. This

was the one I was about to order. No explanation about the two switches.

I have heard loads of stories about nuisance switching on humid nights. All I can say is that we didn't have this problem in our previous bathroom where we had an older Xpelair. I suspect that it may happen on a few very warm and humid summer nights but we haven't had any of those for a few years :-( Nice technology - not sure I would pay extra for it.

Thanks for the VentAxia link - I was focussed on Xpelair products.

Cheers

Dave R

[Thomas]

This is precisely the problem that we are experiencing with our recently installed AirFlow humidistat fan. The blasted thing seems to come on when there would appear to be no reason for it - though I don't have a separate hygrometer to hand to verify that. I'm wondering if external humidity or coldness could be creeping back along my extract ducting and activating the unit?

Unfortunately the problem persists even if I set the unit to its least sensitive humitidy settings (on at 90% off at 80% RH). I should say that the unit does switch off eventually and you can speed it up by directing a hairdryer at it. Even more unfortunately the unit cannot be configured to ignore the humidistat and switch off on the timer or on/off switch. We've had to resort to isolating the unit some nights. Will probably swap it for a simple timer or on/off model.

Thanks Thomas

[David WE Roberts]

Makes me wonder if this depends on the part of the country you are in. We are close to the sea but it doesn't seem to get overly humid (at least not according to the humidity meters in the indoor/outdoor thermometer thingies).