hi-flow bathroom fan

[steptoe]

looking for a high flow bathroom fan, something that will flow a lot of steam/air fairly quickly,

anybody got any recommendations?

room is about 3m square, 2.5m high, and customer wants something a lot better than the standard vent axia they have at present,

wall mounted 4" .

its out of zone 1 so can get away with most variations.

thanks.

 

[Andy™]

what about a centrifugal

 

[Sidewinder]

Steps,

Look at the calcs in the Building Regs and come up with a clearance time/extract volume and go from there?

I don't have the info to hand & I'm working on an EICR write up that is over 40 pages at the moment and about to grow!!!

 

[wozz]

What about one with a trickle option always liked the idea of the room being constanly dried out instead of trying to remove it all at once.

 

[Sidewinder]

Trickle & boost is a good idea wozz.

---------- Post Auto-Merged at 20:48 ---------- Previous post was made at 20:37 ----------

Steps,

BTW tell me where to look & I'll help you with the calcs etc. just not got time to find the info, sorry!

 

[steptoe]

they dont want to go that option, they just dont want any steam in the room while they are in there,

anyone got a decent centrifugal they could recommend?

personally I have a vent axia humidistat and I think its fine, but Ive only got a small bathroom mind.

SW, the vent axia they have exceeds the times required, Im thinking that maybe what they want cleared in the time expected is going to be a tall order for a 4" fan

I dont have much experience of centrifugal in domestics.

---------- Post Auto-Merged at 20:50 ---------- Previous post was made at 20:48 ----------

[quote name='Andy

 

[Sidewinder]

What are the make up air vents like?

 

[batty]

I find the manrose gold ones quite good. I fitted a manrose centrifugal one on a ceiling once that was a big mistake it was very noisy.

 

[steptoe]

gaps below the door,! albeit fairly big.

I did mention this, but he seemed to disregard it,

then I tried to explain that if air doesnt come in you cant take it out, seemed to go above him somewhat,

 

[Sidewinder]

The incoming air needs to come through the gaps at about the same volume as the outgoing air leaves the room.

There is a calc for basic vents at ambient and static flow wrt an energetic exhaust, again not to hand it will be in my BOHS LEV course notes.

Not quite the same level of importance, but, the principles of fluid mechanics still apply.

 

[NozSpark]

I have used centrifugal ones in the past and whenever I fit a ceiling vented one it's always centrifugal

They have near enough twice the flow rate to axial fans and near enough the same as 6" axial ones,,,, however if there's no air getting in the room then no fan is going to work very well

 

[steptoe]

somewhat above me SW,

Im a bit more basic in my calcs as in if I have a 4" fan fitted then I need 16" of air coming in, this means a 1/2" gap below a normal door at least, 1/2"x32"=16" [?]

most draughty doors wont have near this large a gap.! but try explaining that to Mr Homeowner.

I know a 4" fan isnt 4x4, but its not a bad rule of thumb IMHO, maybe? Im not starting 4piR2 at this time of night!

---------- Post Auto-Merged at 21:10 ---------- Previous post was made at 21:09 ----------

centrifugal it is then.

 

[betty swollocks]

I used one of these recently

http://www.ebay.co.uk/itm/High-Power-Line-Loft-Mounted-Extractor-Fan-Bathroom-Wet-Room-Shower-6-/130586278525?pt=UK_Home_Garden_Hearing_Cooling_Air&var=&hash=item642004dbe3#ht_740wt_922

it's not the exact one because I got it at wholesalers and it was a 5" fan not 6 but the extraction figures were the same

Customer already had two standard fans in wet room that were not upto the job so we tried this and it was built like a jet engine but surprisingly quiet for its size

It totally cleared the room in ten minutes flat even clearing the mirrors of steam and if ran whilst in the shower, steam didn't build up, vented through roof tile approx 5m away

 

[Sidewinder]

Area is Pi x r^2, or (Pi x d^2) / 4!

 

[davetheglitz]

Is this a bit basic - but there is an on line calculator on the TLC site which is a good start. I'm often surprised how much air flow is needed and how inadequate a lot of installations are.Suitable Fans

 

[steptoe]

Area is Pi x r^2, or (Pi x d^2) / 4!

pi55 off.!

 

[Evans Electric]

Stepps , how about an in-line fan fitted in the roof space and ducted out . If they want it over efficient try a 6" ACM150T from Denmans.

They can't get that performance for nothing and these are

 

[steptoe]

hole already in wall Deke for 4" and just wanting something more efficient,

they are refurbing the bathroom, heated mirror, UF heating, new LED DL, shaver point etc.

---------- Post Auto-Merged at 21:46 ---------- Previous post was made at 21:45 ----------

Jeezus Betty, these people have small children,!

we wouldnt want to lose one of them!!!!!!!!

High Power In Line Loft Mounted Extractor Fan - Bathroom, Wet Room, Shower - 6" (4823016238160) | eBay &var=&hash=item642004dbe3#ht_740wt_922it's not the exact one because I got it at wholesalers and it was a 5" fan not 6 but the extraction figures were the same

Customer already had two standard fans in wet room that were not upto the job so we tried this and it was built like a jet engine but surprisingly quiet for its size

It totally cleared the room in ten minutes flat even clearing the mirrors of steam and if ran whilst in the shower, steam didn't build up, vented through roof tile approx 5m away

 

[batty]

If the bathroom is cold you will have condensation problems. We have refurbished ours and knocked the toilet and bathroom into one. We now have a towel rail and a radiator and since doing this have not had condensation problems. I have put cabling in ready for a fan but haven't fitted it yet.

 

[Evans Electric]

If you're stuck with the 4" hole then the only way is to go with a cetrifugal . Trouble is they are fairly functional looking but more efficient . They can't have it both ways . I went down this road once with a customer in their bathroom / sauna , loads of steam he wanted shifting . We achieved that but he then complained that the all the heat was being drawn out .