Lobster wrote:

"Owain" wrote in message ...

"Lobster" wrote
| Bathroom is fully internal, so the fan needs an
| overrun timer.
| Having just googled through the archives here, there seem to be
| different schools of thought as to whether I can wire my fan directly
| into the lighting circuit, ie in parallel with the bathroom light, or
| whether it needs to go through an FCU or indeed a separate three-pole
| switch (I'd rather not but want t to be legal). Can anybody enlighten
| me with The Truth? (The lighting circuit will be wired to an MCB in
| the consumer unit by the way.)

1. As the bathroom is internal, the fan must be linked with the light and as
you say an over-run will be required.

2. Item 1 means the fan and the light must be on the same circuit.

3. If you wire it off the lighting circuit you don't need an FCU, as the
lighting circuit MCB at 6A will provide sufficient protection.

4. You do require 3-pole isolator for mechanical maintenance (so you can
clean the inside of the fan with the room light on and without mashing your
fingers). The isolator doesn't have to be in the bathroom or 'under the
control' of anybody working on the fan provided it can be locked off. The MK
one from TLC IIRC is supplied with the lock-off adapter enabling it to be
padlocked off preventing inadvertent reengergisation.
http://www.tlc-direct.co.uk/Products/MKK4857.html


Thanks for both the highly enlightening - and Stefek, entertaining! -
replies! All clear now.

One point - where is it usual to position the isolator switch?
Presumably not within the bathroom? Just inside the loft access hatch
maybe? Or perhaps at ceiling height out on the landing?


The latter, conventionally. For some reason its th only switch in the
house not statutorally placed withing wheelchair access height.



Thanks
David