inline extractor fan

[davebwithane]

Hello

http://www.tlc-direct.co.uk/Products/SLTD160T.html

We bought the fan above and had it installed by a third party. The room we bought it for is approx 2m x 2m x 2m. It is installed in our loft and the duct stretches over a maximum of 3.5 metres. Our bathroom has quite a powerful shower which is connected to a pump for performance purposes. When we are finished in the shower the walls of the bathroom are completely soaked with water and it feels like the fan is not doing it's job. We were not expecting the walls to be wet at all, which is the reason we bought such a powerful extractor fan. Any ideas on how we could improve the situation please ?

Thanks for any help provided
Dave

 

[pbar]

If you hold a piece of paper or card up to the inlet in the room when the fan is on, does it 'grab' it off you and stay there. Just trying to determine if the system is removing air at a reasonable rate, as there are a number of things which might restrict it.

 

[davebwithane]

it does grab the paper, but just about hangs on. I would have thought the suction should have been a lot better. The fan itself is about a metre from the inlet in the bathroom ceiling and from there it is 2.5 metres of ducting to the outlet. I stood outside and watched the outlet while the shower was running, I was expecting to see some steam coming out, but saw nothing. I think you are right about the duct length. The bloke who put it in is coming back today to have a look. Thanks for the advice.

 

[pbar]

it does grab the paper, but just about hangs on. I would have thought the suction should have been a lot better. The fan itself is about a metre from the inlet in the bathroom ceiling and from there it is 2.5 metres of ducting to the outlet. I stood outside and watched the outlet while the shower was running, I was expecting to see some steam coming out, but saw nothing. I think you are right about the duct length. The bloke who put it in is coming back today to have a look. Thanks for the advice.

Yes, with ducting, the shorter the better if possible. The suction should be better than 'just about hanging on'. I have the standard fans which take around 85 cubic metres/per hour at most, although that's in a perfect situation, but they easily hold onto a piece of card. Yours is a lot more powerful than that.
Some things to look out for as regards to restricting the suction -
duct lengths, ducting not held securely around the inlet/outlet and fan, kinks and sharp bends, ducting (if it's flexible) not extended enough.
Let me know how you get on.

 

[sm1thson]

also ensure there is a sufficient gap under the door to allow airflow.

 

[davebwithane]

thanks for the advice chaps. I will update you next week.

 

[davebwithane]

Hello, I eventually got the guy who installed it back in. He changed the duct direction to make it shorter and it hasn't made much difference. I was up in the loft the other day and there is water pooling in the fan itself and I presume this is because of the hot air going through the cold loft, still I don't think that should happen ! It sounds dangerous to me. I got a couple more sparkies to have a look and they both suggested getting an icon60 axial fan, but the ducting for these can only be stretched 1.5m if using flexible ducting (which we have to). Putting a fan through the wall is not an option for us because of window position and overhanging eaves. Any ideas out there for a powerful fan that can be 'flexible ducted' over 4 metres ? Our mould problems are increasing

 

[pbar]

Hello, I eventually got the guy who installed it back in. He changed the duct direction to make it shorter and it hasn't made much difference. I was up in the loft the other day and there is water pooling in the fan itself and I presume this is because of the hot air going through the cold loft, still I don't think that should happen ! It sounds dangerous to me. I got a couple more sparkies to have a look and they both suggested getting an icon60 axial fan, but the ducting for these can only be stretched 1.5m if using flexible ducting (which we have to). Putting a fan through the wall is not an option for us because of window position and overhanging eaves. Any ideas out there for a powerful fan that can be 'flexible ducted' over 4 metres ? Our mould problems are increasing

I'm unsure about a more powerful fan, but as regards to the water you've found, if it's a sizeable amount I think it's unlikely to be condensation. Could it be rainwater coming in from the ducting outlet? Also, leaving the fan to overrun longer will clear condensation forming if you think it is that, might be worth a try leaving it to run on longer.
Some people fit condensation traps and some lag the ducting, don't know how necessary those things are though.

 

[davebwithane]

Thanks pbar. It is definitely not rain water. It's not a huge amount of water, but enough to concern me if you know what I mean.

I might go for this one instead
http://www.tlc-direct.co.uk/Products/SLTD350T.html
350m3/hr as opposed to the one I have now which does 160m3/hr,
that should do the job surely !! It's all 5 inch ducting though which means I will have to change everything .. hope it works

 

[pbar]

Thanks pbar. It is definitely not rain water. It's not a huge amount of water, but enough to concern me if you know what I mean.

I might go for this one instead
http://www.tlc-direct.co.uk/Products/SLTD350T.html
350m3/hr as opposed to the one I have now which does 160m3/hr,
that should do the job surely !! It's all 5 inch ducting though which means I will have to change everything .. hope it works

That sure is a beast you'll have there!
Definitely leave the fan on longer then, if you think it's condensation. If you don't, the fan stops whilst leaving loads of vapour within the ducting, which then pools. Leaving it on for longer after the vapour has left the room, dries it out totally.