Bathroom extractor fan dilemma

[Carnmore]

I'm renovating the bathroom in a central (no window) mid-floor apartment with flat channel ducting and a long duct span (6-7 metres) to the external wall vent. I've removed the original centrifugal fan c.25 years old) and need to decide on a replacement.

Inline fans seem to be the most effective but there is no room above ceiling level to install it. I'm considering installing the fan below ceiling level mid-way along the duct-which would be in a bedroom-with the existing flat channel ducting above ceiling level and boxing-in the fan.

Other options I'm considering are a modern centrifugal fan or a dMEV (continuous running) fan.

Obviously having a fan boxed-in below ceiling level is not ideal!

Can anyone advise on the most suitable and effective option?

Thank you in advance.

 

[brig001]

In the same situation, I used one of these:

Airflow iCON 30 Low Profile Extractor Fan - White | Aidelle_Airflow (72687257)

It’s a bit noisy until it’s open, the pretty much like any other extractor. Keeps our bathroom steam free and we have 8m of 100mm ducting
Brian

 

[ericmark]

I have found main problem is replacement air. It needs dry air to replace what is pumped out, and well fitting doors can mean can't get that replacement air.

So little to do with fan, all about general air circulation.

 

[Carnmore]

In the same situation, I used one of these:

Airflow iCON 30 Low Profile Extractor Fan - White | Aidelle_Airflow (72687257)

It’s a bit noisy until it’s open, the pretty much like any other extractor. Keeps our bathroom steam free and we have 8m of 100mm ducting
Brian

Is it Continuous Running and could you explain the "noisy until it's open" Brian?

Is your duct the circular flexi-hose or flan channel type?

 

[Carnmore]

I have found main problem is replacement air. It needs dry air to replace what is pumped out, and well fitting doors can mean can't get that replacement air.

So little to do with fan, all about general air circulation.

Mine has two wall open wall vents in three rooms with a hallway separating them from the bathroom so my thinking is if the doors are left open there will be a sufficient crossflow of air?

Can I ask which make/model of fan you have?

 

[Wayners]

I have a centrifugal surface mounted ceiling fan with pan connector into solid soil pipe, that's going over my kitchen between ceiling and upstairs floor and out.
10mm gap under bathroom door to let air in.

 

[ericmark]

Moved house since then, no fan in new house, and no problems so not going to fit one, think main reason for no problem is shower cubical seals at bottom so no air circulates when in use.

 

[Wayners]

Moved house since then, no fan in new house, and no problems so not going to fit one, think main reason for no problem is shower cubical seals at bottom so no air circulates when in use.

I had a 25mm gap above our old sealed shower cubicle door. Air came in above head height and out with the cubicle ceiling exstractor. Worked well

 

[Carnmore]

Moved house since then, no fan in new house, and no problems so not going to fit one, think main reason for no problem is shower cubical seals at bottom so no air circulates when in use.

Is no air circulation when is use a good thing?

 

[Carnmore]

Addendum: The 1500mm x 700mm shower tray is fitted in the old bath recess with a fixed glass panel open at the end so shower tray not enclosed

 

[JohnD]

Moved house since then, no fan in new house, and no problems so not going to fit one, think main reason for no problem is shower cubical seals at bottom so no air circulates when in use.

So where does the steam go?

Holes in the ceiling?

 

[ericmark]

We have no problems with air circulation, my only worry is door opens into shower so if one fell then getting one out would need to smash the glass door.

 

[brig001]

Is it Continuous Running and could you explain the "noisy until it's open" Brian?

Is your duct the circular flexi-hose or flan channel type?

I have a timer set to about 10 minutes, which seems to be plenty. Like others have said, getting air in is important and we have plenty

The noise is part rattle from the flaps when it is partially open, and the air noise is louder, presumably because a lot of air is moving through a small hole

The duct is mostly round and metal, with a short flexi where it connects to the back of the fan

Brian

 

[JohnD]

The noise is part rattle from the flaps when it is partially open,

Do you mean you have the rattly flaps type of vent? Like a badly made venetian blind?

It will stop rattling when the flaps fall off in a strong wind.

Get a cowl vent.

 

[RandomGrinch]

Do you mean you have the rattly flaps type of vent? Like a badly made venetian blind?

It will stop rattling when the flaps fall off in a strong wind.

Get a cowl vent.

No, the Icons have wax motor powered flaps on the front...