Help With Wiring Home Air Extractor!

14 May 2007
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United Kingdom
Just moved into a new property.
It has a air exhaust Fan, controlling both the cooker hood & Bathroom, but none of the wires are connected up.
It has a fused switch box, a cable from the the unit that goes into the box, with 4 wires : Brown, Black, Blue, Green/Yellow, and a cable that comes through the wall in the top of the box, with 4 wires : Red, Yellow ,Blue ,Green/Yellow (sleeved/bare).
The fused switch looks like this, and the box itself has a isolated earth connection :


E N L | N L E

e=earth sign

Any help in wiring this up would be appreciated.

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Ummmm . . . Why do we have some

Red, Yellow ,Blue (old 3ph colours)

in a switch drop in our house, which was wired early 90's then?

Surely the new colours are brown black and GREY (OP error?)
brown, black and blue were the old 3 phase FLEX colours.. or 4core flex ( 3 phase and earth )

since the cable is from "the unit" i would guess that it's a pre-wired fan..
Christ - theres so many variations of old colours etc! I shouldn't have got involved lol! :LOL:
No it's not new build. 60's I think.

The Fan is a A.B.B JBDC/CPAV, I think it's swedish, just make it more complicated. The fan is already wired with flex coming out bottom of it's housing.

I expect this was wired in ages ago, pre 90's. But switch is fairly new.

someone screwed up there then..

it is most likely to be fed from the lighting circuit.

it should be a 3 pole fan isolator, not a fused spur I think

a picture of the fan and FCU would be of great use to us to help with this..
Photos of the installation as requested:






Thanks For any help.

Jimmi D

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