Domestic extractor fan problem/question

[Kate]

hey,

Hoping someone may know more on this than I do. Extractor fan above a shower in an en-suite, in-line fan so unit is up in the loft.
I know you can get condensation and "dripping" from the unit. How bad can this get?

Had a customer ask me to look at why their fan had stopped working. It was only 2 or 3 months old. Jumped up in the loft, removed the duct, could have easily filled up 2 buckets with the amount of water that came out. Travelled from the roof tile, right through the duct (had a drop point here) through the fan unit itself, into the duct on the other side. There was another drop point here which had stopped it from entering back into the shower room!

I may be completely wrong, and tell me if I am. But to me, that's far too much water for condensation surely? I was thinking faulty roof tile as this was existing and many many years old.

 

[marc8]

if the flexi duct is not stretched out it will cause system pressure which means the fan will have to work harder, air travels along the edge if smooth it will not get much resistance & the air will be pushed further.
if the ridges in the flexi duct are closed up the air will not roll along the smooth edge & it will start to fold back on itself creating system pressure this then means the fan unit will have to over come the folding air coming back onto itself, if you can shorten the length of tube by stretching it out that will help. cover in insulation as the hot air & vapour will hit the cold air in loft creating more condense in the pipe work.
best way use as much rigid pipe as you can to replace the flexi duct.