Bathroom extractor fans

Rather than Google, I’m turning straight to the vast knowledge base that is STW.

Our current extractor fan is a Vent-Axia, and to be frank it isn’t cutting the mustard in terms of whipping away the steam. Someone did recommend another brand of fan that performs better for a given size/power: problem is, I can’t remember what it was.

It’s a straight ceiling mounted fan, not a remote fan or anything. Like this, more or less

Is it not working?
Perhaps it is now an ex tractor fan….

It no longer obsesses about agricultural machinery?

Does it just need cleaning perhaps? They accumulate an amazing amount of crud over the years.

They don’t last for long so I just buy the cheap ones from screwfix use it for 5-8 years then replace.

No vast experience but having just done two bathrooms over the last couple years, the more recent one has this in:

http://www.screwfix.com/p/vent-axia-vasf100t-4-3-6-8w-silent-axial-bathroom-timer-extractor-fan/6468h#product_additional_details_container

It seems good. Steam clears, isn’t too noisy, doesn’t seem to let a draft in. In a wall rather than ceiling, but claims to do both. Maybe not as quiet as it implies, but it is quiet enough you can listen to the radio/podcasts in the bath ok…

ive had 2 since being in this house, neither have moved any steam, come to think of them as useless.

happy to hear about success stories tho.

Look at the specs! Extraction rate I changed ours cos it wasn’t doing a particular good job, think the new one is 150 m3/hr and the old one were 70m3/hr, big difference

http://www.manrose.com/specifications/showerinlinefanrange.pdf

The middle one

Check how much air it shifts vs the size of your room. also makes a massive difference if you let air in at the point furthest from the extractor.

I think the idea is to fully replace the air 8 times an hour.

I think the idea is to fully replace the air 8 times an hour.

Last time I saw any technical literature (a long while ago) it claimed 15 air changes an hour. This was an old Vortice Tech manual. Things may have moved on since then. When I bought the fan for our bath/shower it shifts about 300? per hour.

mine shifts 1m? per day……

Current requirement for a bathroom fan is for it to extract at a minimum rate of 15l/s. Trouble is with these crappy axial fans is that they’ll only just exceed that when fitted through a wall. Put one in a ceiling, most likely with copious loops of flexi ducting connecting it to the outside world and you’ll find the extract rate drops to little more than bugger all.

Options:

1. Check the ducting and replace with rigid if possible. Fan performance will probably still be pants though, depending on length of run, number of bends etc.

2. Replace fan with a centrifugal unit – much more power to overcome duct restrictions but generally bulkier and, to be honest, ugly. Nuaire Cyfan is one of the best available.

3. Replace fan with a ‘constant flow’ dMEV unit (current favoured option for retrofit condensation control). Check out the Greenwood CV2GIP. Supply to the fan needs a permanent and (optionally) a switched live. Fan runs all the time at low speed (extract around 5l/s) and boosts to 8l/s or more (either from light switch trigger on switched live or from inbuilt humidity sensor).

4. Replace fan with a grille and insert an inline mixed-flow fan in the loft. Airflow Aventa range are very good, powerful and cheap.

Hope this helps.

Not hijacking, but dudie, do you recommend the Greenwood CV2GIP over something like the Vent Axia Tempra?

Only ask as the wife has just told me we’ve got a bathroom man coming tomorrow for a chat about a refit. And I want something!

The Tempra is a single room heat recovery unit, whereas the CV2GIP is simple a continuously running extractor (no heat recovery) so not directly comparable. You pays yer money and all that….Personally not a fan of single room heat recovery (expensive, questionable benefit, not very efficient). The Tempra’s as good as any though, if you want one.

We’ve got a Tempra in our utility room for drying clothes. It’s great as a single room extractor where it’s just a bit humid, it does really well in keeping the room dry without chucking all the warmth outside, but I don’t think it’s what you want in a bathroom; it doesn’t shift that much even in high, and when in high mode it’s really rather loud!

In the bathroom I’m surprised no-one has mentioned one of these mounted in the loft, the good ol’ MF100T:

We’re just getting quotes for re-doing our bathroom and we were recommended these bad boys as being ICON Fans pretty efficient as well as very quiet. The 15 was suggested as being perfectly adequate for the standard bathroom

bookmarked

I’ve just replaced a useless ceiling fan with the Manrose MF100T and it’s superb. Combined with some new aluminium ducting the difference is substantial.

Slight hijack – is it relatively simple to fit a ceiling fan to a bathroom with a flat roof? Currently have to shower with the window wide open just to shift a tiny amount of steam.

Have you got a void? You can get shielded vent covers for use on flat roofs – don’t know how weatherproof or efficent they are.

I’ve also recently put in a Manrose inline fan and while it’s better than the wall fan it replaced, I reckon I can make it more efficient by sorted out the ducting a little better.

In our old house, we had a Manrose centrifugal fan that worked pretty well – even with around 2m of ducting in the loft.
When it failed, my father-in-law said he’d replace it. He stuck in a really cheap axial fan that just did nothing at all. Not the right tool for the job & within weeks we were getting mould forming on the ceiling.
I replaced it with another Manrose centrifugal one & back to decent performance – bit ugly though, as the box protrudes into the bathroom space.

It was this one:

https://www.electricaldirect.co.uk/product/manrose-4-inch-centrifugal-standard-fan-179726?vat=1&gclid=CPCHl-iHwdACFQsR0wodWV8KyQ

When we moved, the new house didn’t have any extractor. An electrican was doing a few jobs so I asked him to put in an extractor for the bathroom. Again, he put in a crappy axial fan, so not long after I replaced it with something more substantial. I bought an Aventa in-line axial fan, similar to the Manrose one that seems to be the go-to choice.

This one:

https://www.voltelectrical.co.uk/products/Ventilation/Extractor+Fans/Airflow+Aventa+100T+-+White/2689944809?gclid=CNjdpaOIwdACFccp0wod0PwNqQ

It works well. Admittedly, if I was doing it again, I’d have gone up to the 5″ version, rather than the 4″ just because, but it’s fine as it is.

In general – centrifugal fans are good at low(er) volumes with a higher pressure difference; So, they can’t push as much, but they can push harder. Good if you have lots of ducting.
Axial fans are good at high volumes with a low pressure difference; so they push a lot of air, but not very hard.

But, then if you can squirrel the actual pump unit away in the loft an inline axial fan is a good choice….

To be honest, the idea behind the Tempra was just to have it running continuously. The bathroom door is generally open (bloody kids…) and we live in a damp wooded valley. It would just help move some of the damp air around the house

When the their shower is going, that would use the normal fan that it always does.

Ideally I’d like a PIV, but we’re a chalet bungalow…

In the bathroom I’m surprised no-one has mentioned one of these mounted in the loft, the good ol’ MF100T:

I just read through the posts to see if anyone had – we have two of these monsters (en-suite and main bathroom) and they are great. My wife has *very* long showers in the en-suite and it clears the steam away almost as quickly as it is created – the mirror will be free from condensation within a couple of minutes of the shower being switched off and the fully tiled room is almost dry. It has been fitted for three years, we both shower daily and there is absolutely no sign of mould starting.

Please note though – look for one like the one posted above and not the one below – it is the replacement version and isn’t meant to be as reliable or effective.

Original still appears to be available

thanks all. Can’t use an inline fan, there’s no access to the space above the bathoom other than pulling up the roof tiles – but to be fair the fan goes in to a duct that just arches over the external wall and out under the soffits, it’s only 24 inches long at the most. Will check out Manrose stuff thanks.

the power to the fan appears to have been run from the lights – if the lights are on we can switch the fan on, but if the lights are off the fan won’t work, so can’t use a timer

the power to the fan appears to have been run from the lights – if the lights are on we can switch the fan on, but if the lights are off the fan won’t work, so can’t use a timer

That sounds like a shonky installation!

Watching!

Whilst we are on the subject – anyone got a solution for draughts blowing back in, or just cold air?

The flappy hooded job I fitted doesn’t seem to make a lot of difference.

I’ve just fitted this 150mm fan into our bathroom. It fits into a hole in the wall and exits via ducting that’s only about 300mm long. It works very well if a little bit loud. Plenty of flow (78 L/sec) for a 3M x 3M x 2.5M bathroom.

I wired it off the Bathroom light switch and it goes off a couple of minutes after the lights are turned off.

Bought from CEF for about £110

The flappy hooded job I fitted doesn’t seem to make a lot of difference.

If you have an inline extractor… (we have one fitted to each of our fans and get zero blowback).

Our bathroom extractor has two of those ^^^ things in, to keep the noise from outside down. I’ve stuck a few tiny bits of sticky backed sponge stuff where the flaps sit to stop them clonking when it’s really windy.

They are much better than the outside louvred things.

I’ve got one of these, it has a built in humistat, not cheap though.
https://www.amazon.co.uk/Xpelair-Bathroom-Centrifugal-Extractor-Humidistat/dp/B004TQ0Q82

There are no fans in my bathroom and I want to install one/ get one installed. Small bathroom but black mould in the corner above the shower so want a powerful fan.

I can drill through the wall near the shower or go up into the loft- which is best?

Any recomendations?

Cheers

If you can go through the loft with a decent inline axial fan without having a long duct run, I would do that.

Depends on your individual set-up though, really.

With the loft option, you can site the vent right above the shower so you are removing more of the steam ‘at source’

As above, I went for an Aventa 100t. It’s works well, but if I was doing it from scratch again I would go for the next size up – the 5″ – just because it’s biggerer….

Thanks I’ll have a look up in the loft to see if its possible. The shower is on an exterior wall so there shouldn’t be much of a run.