Timed extractor fan advice needed

[flameport]

Is that not one of the 3 cables going into the back of the light switch?

Possibly - if the single brown into the switch is the supply and the two in the same terminal are for the fan and the light.
Could also be a loop in/loop out and the single brown is for both the light and the fan, with a connection somewhere else, such as the isolator.

 

[EFLImpudence]

Part F Table 5.2a
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/468871/ADF_LOCKED.pdfView attachment 200836

Approved Documents are merely guidance and what someone thinks you should do.

The only actual Building Regulations In them are in shaded green boxes.

 

[EFLImpudence]

THE Building Regulation Part F:

That's it; there is no more.

 

[YouTarzanMeJane]

Need to see wiring in that as well.

Isolator switch wiring (2 cables from wall, each with blue, brown, earth. Both brown into live on switch, both blues into neutral on switch, both earths in end block)

 

[YouTarzanMeJane]

Approved Documents are merely guidance and what someone thinks you should do.

The only actual Building Regulations In them are in shaded green boxes.

Ah yes. So it is. My mistake.