Water in Loft Inline Extractor Fan

[steveoelliott]

Hi all,

 

We have a loft  inline extractor from a small en-suite that was installed just over a year ago. In fairness we have only actually used the extractor / shower once several months ago but today I turned it on and noticed a strange noise that sounded like the fan was coming into contact with something and from the en suite it sounded like water.

 

Upon further inspection in the loft, when the fan is on, I can hear water that has accumulated within the fan unit. I have deduced this must be condensation from the very cold temperatures we have had recently. The extractor is ceiling mounted in a bedroom with the flexi ducting going up into the loft, the inline extractor fan unit is mounted on a piece of OSB in the loft and then more flexi ducting to a sofit vent.

 

Wondering how best to tackle this... I will of course ask my electrician to take a look but I was thinking about raising the extractor fan perhaps a few inches so water can't collect here but then I read about condensation traps.

 

This must be a common issue with inline loft extractors but not one I considered prior.

 

Thanks...

[ETC]

Change the flexi to solid and insulate the pipe.

[MJNewton]

What sort of flexi pipe is it? The thin single-walled white stuff? If so, insulated flexi pipe is far better and it's also a lot smoother internally resulting in better airflow. 

[steveoelliott]

It’s the thin white flexi pipe currently.

[MJNewton]

This will be much better. 

[ProDave]

Yes poor install detail.  the extract pipe must run straight and flat with a gentle fall to where it exits the building.  I bet your fan sits in a dip with the pipe risong either side of it, a perfect "sump" for the condensation to form in.

[steveoelliott]

2 minutes ago, ProDave said:

Yes poor install detail.  the extract pipe must run straight and flat with a gentle fall to where it exits the building.  I bet your fan sits in a dip with the pipe risong either side of it, a perfect "sump" for the condensation to form in.

Seems to rise slightly to the extractor and then slightly down after to the soffit vent. However, I am thinking that a change to insulated ducting and just elevating the extractor a little will prevent water collecting in it.