bathroom fan ducting

[kath74]

We had a new bathroom fitted last year with an extractor fan, but it doesn't seem to be very effective. The fan motor is in the loft and ducted to the inlet and outlet (in the soffit) with soft concertina type ducting (as used for a tumble dryer).
Would replacing this with rigid ducting improve the performance?

 

[mikej2005]

That's a fairly typical set-up for a bathroom extractor.

The only way you're going to get a more powerful airflow is with a more powerful fan - I wouldn't have thought that changing the ducting would make much difference.

 

[daytona]

it will improve it a little but i suspect in this case not enough to warrant all the work.


how long is the duct run?
how many bends in the pipe?
its not been squashed somewhere has it?


btw,how many litres per minute can the fan extract?

it might not be on overrun for long enough,how long does it stay on for after you turn the light off

 

[kath74]

Thanks for your help with this.

Over the weekend we got the info from the fan, a Manrose PFE4321 shifting 85m3/hr.

I emailed Manrose this morning & they've phoned me within an hour. Seems like the length of the ducting may be where the problem lies.

Just wanted to put in a good word for them, very prompt & helpful service.

Thanks all.