rtcosic
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- Warwickshire
If a fan discharges vertically through an unheated roof void like that it needs a condensate drain (and a cap).
See NHBC requirements below:
The installation instructions from Expelair say the same thing:
:
I had incorrectly installed fans in my new build and the ceiling failed within 6 months of moving in due to condensation running back down the exhaust duct:
You will note the superb workmanship on the fan mounting - one plasterboard screw into a cheap wall plug and 'hope & pray'.
The electrical contractor replaced the fan twice due to condensate running over the circuit board.
They 'declined' to correct the problem because the exhaust didn't run vertically upwards as in the NHBC drawing - it was at a jaunty 85 degree angle!
I have replaced the extract system in its entirety with an MVHR unit. The volume of condensate discharged is quite remarkable.
See NHBC requirements below:
The installation instructions from Expelair say the same thing:
I had incorrectly installed fans in my new build and the ceiling failed within 6 months of moving in due to condensation running back down the exhaust duct:
You will note the superb workmanship on the fan mounting - one plasterboard screw into a cheap wall plug and 'hope & pray'.
The electrical contractor replaced the fan twice due to condensate running over the circuit board.
They 'declined' to correct the problem because the exhaust didn't run vertically upwards as in the NHBC drawing - it was at a jaunty 85 degree angle!
I have replaced the extract system in its entirety with an MVHR unit. The volume of condensate discharged is quite remarkable.
