ECN Forum Forums General Topics of the Trade Non-US Electrical Systems & Trades Bathroom Exhaust Fans

If you Install an exhaust fan with timer, & use the 5A Lighting supply Circuit, do you have to install a 3 Pole isolating Switch?

Under Irish regs, you do thesedays.

Have to be able to isolate the permanent live, the switched live and the neutral for maintenence.

If you've fans with humidistats the fan isolation switch can be very useful. We have them and on very humid days the fans can start to run constantly!

[This message has been edited by djk (edited 10-17-2005).]

Thanks DJK

Here in NZ you would not require a 3-pole isolator.
Depending upon your type of fan, the phase coming in would be fed to the light switch and then on to the fan isolator, as in continuously live.
The fan isolator would have a switch that looks like this:



The fan supply needs to stay energised so that the timer works.
There is no need to break the Neutral.

The 3-pole isolator has become the norm here for timed fans:



MK is now making a version with a lock out provision, although from the pictures I can't quite figure out how the padlock is supposed to work:



I'm trying to think when these isolators first appeared. I think it might have been with the 15th edition (1981).

Thanks for that Lads!
Is the Isolator allowed by law to be mounted in the bathroom, or does it need to be mounted outside the bathroom?
Can it be mounted in the loft above the bathroom? (Trumpy..do you play for the All Blacks? if you do I'll see you in Cardiff on Bonfire-night!!!)

Well, by law you can put it almost anywhere you like in a private house, since there is nothing legally enforcable about BS7671.

However, as far as the Regs. are concerned it can go inside the bathroom, subject to being located outside the appropriate zones as for any other switch.

I wouldn't locate the isolator in the roof space unless the fan itself is mounted there (i.e. an "in line" unit with ducting to the grill over the tub/shower).


[This message has been edited by pauluk (edited 10-19-2005).]

Thanks Paul, very helpful. (AS usual)!

U/Dog,
Hehe,
At one time I probably could have, however these days, it's called Middle Age Spread and we all know what that means.
I wouldn't even get in as an Assistant Deputy Understudy to the Orange Boy.

You could probably get a game easy for the Lions then!!!!