Hi,

Can you help ?
The overhead extractor fan that I've purchased to go over our hob has
a plastic adapter on it. This attaches to the extractor hood and goes
out on circular 125mm (~5"). Although there are parts an accessories
for 125mm there are far more for 100mm (~4") to build the ducting to
the outside world.

Do adapters exist that take 125mm circular to 100mm circular, or to
push my luck :-P 125mm circular with 90 degree bend to rectangular
100mm x 55mm ?
- If so where ?

I've already found my bodge solution and that is to use a 100mm
threaded hose connector with plenty of ducting sealing tape ! But I
thought we'd try and do the correct way first.

Cheers - Oliver.

Do you really want to do this? The kit will expect 125mm and by cutting that
down to 100mm you will be severely restricting the airflow. I have just
taken delivery of a new cooker hood with 125mm outlet and while I agree that
it's more difficult to get 125mm ducting stuff than 100mm - especially with
the ducting in aluminium which I wanted because it's going to be visible -
it is possible. Try:

http://www.domusventilation.com/

NB I found it astonishingly difficult to get hold of their stuff even when I
had identified the exact part numbers from the catalogue - nearly all the
stockists suggested by the manufacturer said they weren't (stockists that
is) or had a few bits only in stock and couldn't/wouldn't order the less
common stuff for me. Domus did eventually point me to Starkey Systems on
01905 611041 or http://www.centralvacuums.co.uk and after a couple of
failures the stuff arrived mail order.

rrh wrote:
Do you really want to do this? The kit will expect 125mm and by cutting that
down to 100mm you will be severely restricting the airflow. I have just
taken delivery of a new cooker hood with 125mm outlet and while I agree that
it's more difficult to get 125mm ducting stuff than 100mm - especially with
the ducting in aluminium which I wanted because it's going to be visible -
it is possible. Try:

It depends.
IIRC, the restriction is about 2.5 times for 100mm pipe.
So if you'r using 1m of 100mm pipe, it'll be similar to 2.5m of 125mm
pipe.

Not too sure of your layout, but better to go up in duct size than down!
That way you get 6" (150) stuff - readily available and (more importantly
perhaps) you decrease rather than increase the velocity for a given air
flow - therefore should be less noisy.

Phil

"TheScullster" wrote in message ...
Not too sure of your layout, but better to go up in duct size than down!
That way you get 6" (150) stuff - readily available and (more importantly
perhaps) you decrease rather than increase the velocity for a given air
flow - therefore should be less noisy.

Phil

Thanks to all that have replied, you've given me plenty to think
about. I should have provided some details of the ducting run I'm
thinking of doing. Some of the points made would be very valid on a
larger run, but I'll be sure to consider them in this run that is just
less than 2 meters. To give you an idea of where I up to on this
'do-er' up property, please see the URL below.

http://oli4uk.tripod.com/ducting01.htm

Again, Thanks to all that took the time to reply.

- Oliver.

On 25 Jun 2004 02:18:12 -0700, Oliver Brearley wrote:


Do adapters exist that take 125mm circular to 100mm circular, or to
push my luck :-P 125mm circular with 90 degree bend to rectangular
100mm x 55mm ?
- If so where ?

Screwfix part 10684