water in ducting from shower extractor fan

[bernardgreen]

An urban based eco warrier aquaintance of mine did make a "system" by dissecting the works out of a domestic fridge and re-packaging them with a fan to blow the damp air over the ice box. He said it worked but the small amount of "distilled water" that dripped of the ice box suggested it was not up to the task.

 

[JohnD]

I once had a Dimplex ventilation unit that extracted heat from the outgoing air to warm the same amount of incoming air.

probably not worth the trouble though. An extractor creates a slight vacuum in the room and prevents steam and smells diffusing through the house.

 

[Ackoman]

Necro......

Where do you route the water collected by the condensation trap to?

 

[crystal ball]

8 years later ?

 

[Ackoman]

8 years later ?

Your maths is impeccable

 

[mwatsonxx]

Necro......

Where do you route the water collected by the condensation trap to?

Slope the duct to wards the vent and ensure it is totally wrapped in insulation, condensation traps are unnecessary.

 

[Ackoman]

Slope the duct to wards the vent and ensure it is totally wrapped in insulation, condensation traps are unnecessary.

What if the vent is in the roof, rather than in the soffit board? Another thread suggested that venting through the soffit boards is potentially problematic due to the wet air simply being blown back into the loft.

 

[John D v2.0]

Epic zombie thread revival!!

And use rigid duct, keep it as flat and short as possible so no vertical, insulate it as a above posters say and even get a fan with a constant trickle extract if possible to keep the duct warm and dry.

 

[Ackoman]

Epic zombie thread revival!!

And use rigid duct, keep it as flat and short as possible so no vertical, insulate it as a above posters say and even get a fan with a constant trickle extract if possible to keep the duct warm and dry.

But I've been advised to extract through the roof, rather than through the soffit boards - so there will have to be some vertical

 

[JohnD]

a hole in a roof can leak.

 

[John D v2.0]

But I've been advised to extract through the roof, rather than through the soffit boards - so there will have to be some vertical

Conflicting advice then! Maybe there's no ideal solution, just make the best

 

[DrPhil]

This seems to be the place for epic bumping so I'll join in rather than start a new one.

Similar situation, I've got an extractor fan in the ceiling of the ensuite in an apartment. Since winter I've been getting water dripping back down through the fan. I climbed into the roofspace (it's a top floor apartment) and found that the ducting (flexible, sorry) wasn't even connected. It came out of the fan, over a beam and then draped into a big U bend which unsurprisingly was full of stale water, and then was just draped over another beam! So whatever steam was making it beyond the U bend was just wafting out into the roofspace!

Anyway I got a guy to connect the end of the ducting up to the connection in the external roof, (couldn't do it myself at the time as it's about a 15ft gap from the ceiling to the external roof) so now the duct is vertical, but I'm still getting drips. Not as much, but still there.

Should I just pull the lot down and replace it with insulated flexible duct? It's not quite a vertical run but I suppose I could just put the last metre flexible. Or would I be better to put in a condensation trap in the lower part of the duct, it is solid for the first foot or so out of the fan.

I'll try to add some pictures in a minute.

 

[SFK]

Dr Phil,
For me the dew point - where my shower vapour was converted into water - was at the point where the pipe went through the roof (the pipe was cold there from the cold tiles and the cold air outside).
So for me changing to an insulated pipe inside the loft space did help a little, but almost the same amount of water was forming at the same location as always and dripping back down.
I then fited a condensation trap with the water piped to go out through the soffit.
So to answer your question, I feel you will still need a condensation trap and suggest you start by fitting a condensation trap in the lower section.

And in general I would now always recommend exiting through the soffit boards.

SFK

 

[DrPhil]

This is how I found it, just above the picture the duct was hung over another beam.

And this is it now where it exits the roof.

 

[Leofric]

Regarding a current post on problems with vertical ducting from extract fans in bathrooms , looks like people have been having trouble with condensation going back several years on here
Repeating another's comments but ' warm moist air going through cold duct in loft = condensation '