Dampness in an extractor fan.

[stedon1]

Hi, I installed a manrose in line centrifugal fan in a bathroom 7 months ago. I got a call last week to say it was making a strange noise and wouldn't switch off. On inspection there was an inch and a half of water lying in the fan unit itself and some dampness in the compartment that houses the connections even though there isn't really any way for water to get in. The fan is ducted to an outside soffit. Has anyone seen this before or have any idea what is causing it. Many thanks.

 

[ban-all-sheds]

Does the ducting run uphill through anywhere which is colder than the bathroom?

 

[riveralt]

I assume that the inline fan is located in the attic.
Also is the fan is shifting the steam the correct way and there is
no backdraft film on the fan or if fitted it moves when the fan is operated.

If so is it level?

If there is a kink in the hose before and or after the fan?
Is the soffit exit blocked?

 

[JohnD]

1) tilt the horizontal part of duct so water runs towards the outside

2) wrap the duct in loft insulation to keep it warm and combat condensation

 

[stedon1]

The fan is located in an attic and is pulling the steam in the right direction. There is a backdraft shutter which i think has been opening correctly. There is a slight kink in the ducting between the fan and the soffit but not very much. Not all of the ducting is going downhill after the fan, some of it is level at best. The total length of the ducting between ceiling and soffit is roughly 4 metres.

 

[mointainwalker]

From the way you write, it would seem that you are providing a ( presumably paid-for ) service but you are unaware of the certainty of condensation occuring when ducting steam through an un-heated void.

Even when it occurs you need help to diagnose it and suggestions for solving the problem.

This is pure incompetence and I think you should fit f.o.c. a new fan ( after insulating and optimising the pipe-run ) as the existing unit has surely had its operating-life impaired.

Are you a qualified electrician ?

 

[securespark]

I'm a big believer in condensation traps.

 

[electronicsuk]

I'm a big believer in condensation traps.

Trouble is that you need to have access to a drain, which isn't always going to be that easy in a loft. As a minimum it would be sensible to use solid wall ducting such that there aren't any areas for the water to pool, and insulate it to prevent so much condensation occurring when the warm water vapour contacts the cool duct walls. If it's not running downhill away from the extractor and you can't adjust that in any way, you'll definitely need to fit a condensation trip.