shower extraction fan query??

[unclebuck001]

i need to install and extraction fan above my shower bath its a water-mains shower not electric,
im thinking to wire it from the light pull switch to a double pole pull switch and then to the fan. would this be correct as far as regs go?

do i need a triple pole islator out side the bathroom as well?

also what size bonding dose the fan need if any? thanks paul

 

[comms]

Use one of these in line extractors no bonding (4mm) required then.

http://www.tlc-direct.co.uk/Main_Index/Ventilation_Index/4_Inch_Fans_Duct/index.html

Supply taken from lighting (L / N / SL / E) into 2x 3 amp fuse for SL & L (I use grid system fuses + 3 pole switch in a dual back box) then into triple pole isolation switch then onto the fan.
Or
Supply taken from lighting (L / N / E) into grid system fuse for L, then onto double pole switch (no timer over run)

 

[philrosenberg]

For my fan with overrun requiring, live, switched live, neutral (no earth as double insulated) I took a feed from the lighting circuit to a FCU then a double pole switch for isolation (these are in the airing cupboard adjacent to the bathroom), then from here I ran twin+E to a single switch by the bathroom door for turning it on and off day to day (you could use a pullcord inside the bathroom). This meant that I had at the double pole switch a live terminal, a neutral terminal and a switched live loose wire to which I connected a terminal block this could then be connected to three and earth to go to the fan. This all means the fan has one fuse rather than having to have two fuses, one on the live and one on the switched live, which somehow didn't seeem right. Diagram below

If you want the fan to come on with your light then replace your single pole light switch with a double pole one an use one pole for the lights and the other for the fan.