Hi,

We're currently having a shower put into our 2.2x2.5m bathroom, and I
understand we need to upgrade the extractor fan. Currently we have a
ceiling-mounted centrifugal model, which has solid plastic ducting
that takes it up from the bathroom false ceiling, and then lengfhways
through around 4-5m to an exterior wall.

I've worked out that 20x the volume of the bathroom, as recommended
when there's a shower fitted, would need 180m^2/hr flow rate. Also,
that it'd have to be a centrifugal to force the air along the 5m duct.

Trouble is - they're quite hard to find. I've come close (Manrose Pro
Showerlite Centrifugal Chrome 35W Shower Fan Kit on Screwfix), but
these require the fan itself to be fitted inside the ceiiing. Do-able,
but expensive.

Can anyone suggest any other suitable fans? Do I really need a 20x
flow rate, and will an axial fan do?

Thanks!


Damian

"dskeeles" wrote in message
...
Hi,

We're currently having a shower put into our 2.2x2.5m bathroom, and I
understand we need to upgrade the extractor fan. Currently we have a
ceiling-mounted centrifugal model, which has solid plastic ducting
that takes it up from the bathroom false ceiling, and then lengfhways
through around 4-5m to an exterior wall.

I've worked out that 20x the volume of the bathroom, as recommended
when there's a shower fitted, would need 180m^2/hr flow rate. Also,
that it'd have to be a centrifugal to force the air along the 5m duct.

Trouble is - they're quite hard to find. I've come close (Manrose Pro
Showerlite Centrifugal Chrome 35W Shower Fan Kit on Screwfix), but
these require the fan itself to be fitted inside the ceiiing. Do-able,
but expensive.

Can anyone suggest any other suitable fans? Do I really need a 20x
flow rate, and will an axial fan do?

Thanks!


Damian


Leave the original in place and search for an inline extractor to supplement
the push through the longish run of ducting. Like one of these
http://www.plumbworld.co.uk/greenwoo...ine-1949-17149 installed
into the center of the duct in the loft. This solution keeps the existing
fan to push the moist air into the duct and uses the second fan to drag and
push it through the final part of the vent. It's a technique used on many
industrial extraction systems, to keep the weight and noise to a minimum.
Many smaller fans just keep the air moving through the system, instead of
one big fan doing all the work and creating noise and being bulky.

Simple installation that minimises damage to surrounding decoration in the
bathroom. Connects in to the existing wiring scheme. I've also seen them
connected individually for use on different situations in bathrooms with
loos. The inline extractor is used for just air change when there are
smellies, and both fans used when the room is filling with moist air.

There are many to choose from, so have a search for yourself. You may even
find a better solution to match the new decor' you are going to have.

Have fun, and good luck with it.

On Nov 23, 8:25 pm, "BigWallop"
wrote:

Leave the original in place and search for an inline extractor to supplement
the push through the longish run of ducting. Like one of thesehttp://www.plumbworld.co.uk/greenwood-efb100-inline-1949-17149 installed
into the center of the duct in the loft. This solution keeps the existing
fan to push the moist air into the duct and uses the second fan to drag and
push it through the final part of the vent. It's a technique used on many
industrial extraction systems, to keep the weight and noise to a minimum.
Many smaller fans just keep the air moving through the system, instead of
one big fan doing all the work and creating noise and being bulky.

Thanks - I did see one that had a solo inline fan - it is appealing,
but the trouble is we're in a flat, and the ducting is boxed and
painted in along the top corner of the corridor and kitchen. Hence
there's no space for a fan, along with a fair bit of drama in keeping
it tidy and getting power to it.

Half of this DIY malarkey involves wishing for an alternative house to
build it into.... :-(

"dskeeles" wrote in message
...
On Nov 23, 8:25 pm, "BigWallop"
wrote:

Leave the original in place and search for an inline extractor to
supplement
the push through the longish run of ducting. Like one of
thesehttp://www.plumbworld.co.uk/greenwood-efb100-inline-1949-17149
installed
into the center of the duct in the loft. This solution keeps the
existing
fan to push the moist air into the duct and uses the second fan to drag
and
push it through the final part of the vent. It's a technique used on
many
industrial extraction systems, to keep the weight and noise to a
minimum.
Many smaller fans just keep the air moving through the system, instead
of
one big fan doing all the work and creating noise and being bulky.

Thanks - I did see one that had a solo inline fan - it is appealing,
but the trouble is we're in a flat, and the ducting is boxed and
painted in along the top corner of the corridor and kitchen. Hence
there's no space for a fan, along with a fair bit of drama in keeping
it tidy and getting power to it.

Half of this DIY malarkey involves wishing for an alternative house to
build it into.... :-(


The size of these inline extractors is suitable for inside the boxing.
Remove one face board outside the bathroom and fit the fan. Pull the cable
over to the fan in the bathroom and connect it in.

These fans are meant to fit inside a 110 mm pipe.

On 23 Nov, 21:22, "BigWallop" wrote:
"dskeeles" wrote in message

... On Nov 23, 8:25 pm, "BigWallop"
wrote:

Leave the original in place and search for an inlineextractorto
supplement
the push through the longish run of ducting. *Like one of

thesehttp://www.plumbworld.co.uk/greenwood-efb100-inline-1949-17149
installed


The size of these inline extractors is suitable for inside the boxing.
Remove one face board outside the bathroom and fit thefan. *Pull the cable
over to thefanin the bathroom and connect it in.

These fans are meant to fit inside a 110 mm pipe.

Thanks!

I had a look, and thought I might be able to place one just inside the
kitchen, around 2m along the duct, and feed the power cable down the
duct to the grille.

However - my wife regards it as 'scope creep', so I've had to continue
with a 'bolt-on' solution for now. I've ended up choosing an XpelAir
DX200 (http://www.justfans.co.uk/xpelair-dx200-p-231.html) - on the
basis that we can just replace the old fan with it, maybe even recess
it in the ceiling space without having to open it up entirely, and
then play with the speed and timer adjustments until we find the right
combination of noise, duration and extraction rate. Even this is only
rated for 107m3/hr, against my 180 requirement, but I suspect from the
scarcity of high-flow fans that this isn't always followed. Even if
the room over-steams up during a shower, we can set the timer to run a
bit longer to make up for the low rate.

Also - if this proves not to be enough, then I could always add the
inline fan as well later on - and the two together should permit a
quieter flow setting on the first.

An in-duct fan would be a nicer engineering decision, but a less
comfortable decorating one in this case....


D