Bathroom extractor

[Namechanger1404]

Can anyone recommend a really good fan with humidistat, bathroom has no windows and has suffered from damp in the past.

If it has no windows, where does the fan go? Wall, ceiling? There are some very good ducted ones that are usually fitted in the ceiling because they are bigger (and more powerful) than ordinary wall ones. It is easiest if you have access to the loft above.

How long is the duct? Is it 100mm diameter?

Some photos would help.

Is it wired to the light switch?

Hi piglet it’s a flat. Fan in the ceiling above the bath, has a permanent live, 100mm. Was looking at the envirovent silent 100T with humidistat?

so you can't see the duct?

and it isn't wired to the light switch?

where do you think it goes?

is there an old fan up in the ceiling?

Hmmm..I will ask those questions piglet

The Envirovent Silent 100T with humidistat is excellent. We put in a new bathroom with crap extractor and started getting mold very quickly. We replaced it with the one above, and haven’t had an issue in 3 years. We also put a timer one in an under stairs, windowless toilet, and it stops any smells etc.

piglet I think it will be 4 inch duct size and yes there is a switched live from the lights as well as a permanent live.

magic great..thanks for the feedback

it's one of the modern fans that uses very little electricity, and has a noise of about 25db, and a nominal throughput of about 80cu.m/hr.
100mm is the usual duct size, though some are bigger. If the duct is long it needs a more powerful fan.

I'm not too keen on humidstat extractors; some of the extraction requirements in a bathroom are not humidity related. I can't see any that have both a humidstat, and a switch-on from the light switch each time the bathroom is used, which is my preference. I just looked and could only see the Airflow Icon, which has an optional add-on module with a pull cord to override the humidstat, which is not quite the same thing but may be useful after curry night.

It would be useful to know how much space you have available in the ceiling. There are ducted inline fans which can have two or three times the power, and would be more suitable in a shower room.

People who dislike extractor fans usually say it's because if noise (but modern ones can be extremely quiet) or cost of electricity (but they will typically run for more than a hundred hours on 14p worth of electricity).

update

by burrowing into the installation instructions, I found a Soler & Palau extractor that allows switched override of a humidstat fan type CHZ(see case 2 on page 10) you you could use the light switch to start it while also having the humidstat start it if the room becomes damp.

It retails at about £88

It's possible that other humidstat fans also have this facility, but it was hard to find it.

S&P is another very good maker of modern quiet fans. I have no connection with the maker or supplier, though I have used them.

I find these modern fans very quiet, and inaudible when the door is closed (for best noise reduction I recommend an automatic closer and a heavy fire door, even though this is not required on a bathroom by fire regulations. Modern cheap hollow doors offer negligible sound reduction). Parp!

p.s

I just looked at the installation instructions for the [[https://www.envirovent.com/product-downloads/9023003902_SILENT-100_Envirovent26-03-14_1.pdf Envirovent 100}} and as soon as I saw the first pictures I noticed something curious.

Can you spot it?

See Case 2 on page 9.

Mine works both from the light switch and the humidistat. It comes on itself if DH is in the bath without the main light on so I know it defintely works.

sounds ideal

piglet I don’t think there is a lot of room above the fan, it’s a first floor flat in a 3 storey high block. The envirovent link you sent isn’t highlighted so can’t access. I’m concerned that, as there is no window it would get very steamy in there, none of the walls are exterior if that’s of any interest? You are very knowledgeable..thanks a million

magic that’s just what I’m looking for

Hi @Namechanger1404

We just got this Xpelair CV4S from the aircon centre www.airconcentre.co.uk/products/Shop+By+Brand/Xpelair+Store/Bathroom%2C+Shower+%26+Toilet+Fans/Xpelair+Simply+Silent+Range/Xpelair+Simply+Silent+CV4S+Square+Extract+Fan/3273955046

You may need the wall kit www.airconcentre.co.uk/products/Shop+By+Brand/Xpelair+Store/Xpelair+Accessories/Xpelair+Grille+Accessories/Xpelair+The+Simply+Silent+Contour+-+Wall+Kit+Square+%28Brown%29/3916401115

without some photos, I don't know how your fan is fitted or how much room there might be.

I will try and get a photo piglet

piglet here are the photos

I see two holes. Are they both extractor? Or is one a downighter?

I think I see a duct, is it rigid plastic 100mm? (Some are flexible hose.)

It looks like the fan will be fixed to the ceiling, although (you will need a torch and steps) there might be a false, or suspended, ceiling, with a gap under the floor of the flat above. In this case there may be a metal grid hung on threaded steel rods. There might be sound-muffling mineral wool. A gap means it is possible to fit a more powerful extractor.

Has the old fan been thrown away? What did it look like?

We have 3 envirovent silent 100s. All are both switched with the light and have humidity sensors and switch on independently of the light/stay on as long as is necessary. No mould problems.

P.s.

I can see your work is already underway, so if you want to get on with it without delay, I think your suggested fan will be fiñe, but have it wired as "case 2"

I have an almost identical one (without humidstat) and even the mirror doesn't steam up.

piglet as you say I think it’s needed quite quickly now so as it seems it’s quire a reliable fan, I shall go with this. Can you just clarify ‘case B’ please?

it's the method of connecting shown in the installation instructions page 9 or 10, so that it will come on with the light switch, and also with the humidity detector.

click "installation guide" on the product page
www.envirovent.com/home-ventilation/products/bathroom-extractor-fans/silent-100/

and it should open the instructions as a pdf

www.envirovent.com/product-downloads/9023003902_SILENT-100_Envirovent26-03-14_1.pdf

Look for "case 2" on page 9

Figure 8 is on page 6

On the terminal block inside the fan case, "Ls" means "switched live" i.e. the wire from the light. It is usually taken from the ceiling rose (might be the light switch) and I understand is already present in your ceiling.

"L" means "permanent live" which is usually also taken from the ceiling rose.

"N" is for neutral.

All need to be connected for it to work.

There may also be an earthwire, which this fan does not need. It should not be cut off, but terminated neatly.