Extractor fan recommendation?

[SunnyUpNorth]

One of the most boring threads! But following on from the bathroom thread could anyone recommend an extractor fan that is:
Powerful
Silent
Humidity detector
Can have an isolator switch

Any good brands? Roughly how much should this sort of thing cost? Thanks.

If you want quiet and you're fitting it yourself I'd get a centrifugal one with a balanced impeller and 100mm rigid ducting, and fit it outside the room eg loft space. Not sure of the cost, but it should basically be silent if done properly.
I've got a balanced air supply/extract system and when it's doing 30l/s each way which is double the amount needed for the bathroom, all you can hear is a bit of wind noise.

We put a new one in the downstairs bathroom, the fan part is actually under the floorboards in the landing upstairs and it vents out at the back of the house. It's very noisy from inside the bathroom, can;t hear anything upstairs. The noise isn't the actual fan, it's the air being sucked through that makes all the noise. We got one of these fan

have you got access to the space above the ceiling, for example in a loft? Or does it go straight through an external wall?

JohnD - sounds like good recommendation. Can you share any links?

The one I got was on eBay a duplexvent dv72, but it cost 300 pounds and does supply and extract with heat recovery. I'd expect you can get extract only for 100. The point is not to go for whatever homebase sell cheap, but get a well designed unit designed to be ducted out. Hope that helps!

I might, if you can answer my questions.

Sorry been on a long train journey with no wifi or 3G!

Thanks for the replies.

It would be going directly out of an external wall, can't access anything above it.

no need for a ducted fan then, which would look unsightly (they are rather big)

If you have not made the hole yet, a 125mm or 150mm will enable you to fit a larger fan, which can be quieter and more powerful than the typical 100mm.

Unless it is directly above a bath or shower and within 2250mm of the floor, you do not need an extra-low voltage fan. If it is liable to be splashed or squirted, you will need a water-resistant fan, which is more expensive.

A cheap builder's fan typically has a throughout of 80 cu.m/hr, which is not enough.

This one is a good maker, three times as powerful, quieter, and has a ball-bearing motor so it runs quietly and will not wear out quickly.

It has an overrun timer, so that, assuming you turn it on when you enter the bathroom and it runs during and after your shower while you brush your teeth and cut your toenails, there will not be much damp, and it will finish off during the adjustable run-on time. It has a backdraught shutter.

It needs a 6-inch hole in the wall, lined with plastic duct. I recommend a cowl vent on the outside to keep the weather out.

I recommend you have it wired to come on with the light switch. Otherwise people will forget to turn it on. It is quiet and cheap to run, so no need to worry about using it.

If you feel the need for increased cost and complexity, and reduced effectiveness and reliability, you can get a humidistat version.

Thanks for the detailed advice PigletJohn. We had cheap useless version in old house so don't want to make same mistake.

Not got any fan at mo, do you think they are a must? We tend to have doors open when shower or bath in use. Is outside or loft venting better? We had almighty draught blowing through before do reluctant to replicate outside vent.

Great thanks PigletJohn, I will have a look into that one. We have one in place already so there is a hole but presumably that could be made bigger if necessary.

Oo thanks for this thread. I had the exact same question but ours will be going into the loft. I assume the advice/recommendations are fairly similar?

If you're going into the loft you also have the option of a ducted fan meaning the whole motor can be outside the room. All the rest applies, although 150mm seems huge, but indeed it would be quieter.
Regarding the humidistat thing, clearly piglet John doesn't like them, but they might suit you if people don't use the light for showering, or if you don't want to lose heat if you spend time in the bathroom doing other things.
Having said that, a rare but clever option would be to have a flow sensor on the hot water inlet of the shower!I don't think any do that as standard though.

If yoh have loft access, a ducted inline fan is better.

On phone just niw but if yoh use Advanced search, loft fan, PigletJohn you will find similar threads.

here are a few

Some say the vent-axia is more reliable than the xpelair.

The Manrose is attractively priced.

Compare the air throughput (cubic metres per hour) and the noise (db).

The dual-speed fans can usually be wired as fast or slow, but not controlled by switch, unless their is a compatible speed control sold separately (may be surprisingly expensive)

Use rigid duct, not flexible, and insulate it to prevent excessive condensation. Slope it slightly so any water runs outside.

another good make

lots more on this site. Avoid the cheap ones.

Thanks ever so much!

Timely thread, I was just about to start one!
Taken on board the above re bathroom fans but Piglet John could you suggest a fan for a kitchen and utility room. These are both in the (semi) basement of a four storey town house. That is full basement one end of the house but open to the garden at the other. The utility in particular gets a bit musty smelling although we have improved it a lot by stripping back to the lime plaster. I was researching how to improve the situation and was wondering about a fan triggered by humidity? But you are not keen? Can I ask why?
Thanks

you could get a ducted fan to suck from both rooms, and leave it constantly running at low speed.

Probably listed as "mixed flow" fans

They are not used much in domestic homes

have a browse on www.tlc-direct.co.uk/Technical/DataSheets/SolerPalou/TDsilentTIMERS.pdf

A large slow one will be quieter than a small fast one.

Have a good look for waterpipe and drainage leaks. Observe your water meter if you have one.

Thanks Piglet John I'll check that out.