Bathroom Extractor Isolator

[SDES]

So, customer wants an old bathroom extractor fan replaced. Not sure how original was wired as it has already been removed and I haven't yet investigated. They want it to operate via a second pull cord in bathroom simply on/off. Not a problem if that's was they want and wont be swayed.

However, does the fan then need a separate isolator switch? 

Is there a Reg that states an isolator is required.
Any thoughts??

 

[Murdoch]

I am not aware of any regs about isolation switches for fans ...... willing to be proved wrong........

 

[ProDave]

We have had this debate before and nobody has ever shown me a reg in BS7671 that says a fan needs a local isolator switch.

 

[Murdoch]

Isn't there a reference somewhere about rooms with no windows and fan isolators (so that you can maintain a fan without turning off the circuit) 

I am clutching at straws though :B

 

[Evans Electric]

I 'm never sure either to be honest .  I put 'em in to save any comebacks .;

One assessor picked my up on using a spur , outside the room ,  3A fuse , which isolated the downlights and the fan  ...ensuring the trigger wire was dead.   However he maintained that to work on the fan  you'd want the lights on so a spur was wrong and 3 pole  should be fitted .  

I expostulated   :C   that I managed to  install cables , fit down lights  & fan ....all without  the lights on  .. but that wasn't good enough ...it had to be a 3 pole isol. 

However  if I remember correctly he found fault with virtually everything  I'd done ........looked at a small swa I'd run  and decided that ..yes ...he'd have fitted one extra cleat to what I'd done .  

Even the lady customer commented after he'd left  that there was no pleasing that guy ... bet you'd like a cuppa after that lot .  

 

[Hefferl]

Isn't there a reference somewhere about rooms with no windows and fan isolators (so that you can maintain a fan without turning off the circuit) 

I am clutching at straws though :B

The reference you mention is included in the Electrician's Guide To The Building Regulations (pg 65)

 

[ProDave]

I have a "thing" about NOT having a fan isolator in a rental property. You do not want to give the tenant the mechanism to disable the fan, then complain the bathroom is damp and mouldy.

I don't buy the maintenance argument. As mentioned, we have no problem changing a light fitting in a dark room with the circuit isolated. And lets be honest, the 5W motor in a bathroom fan is not powerful enough to cause any physical harm is you are daft enough to remove the cover with it running.

I am convinced people have picked up on the requirement for a big industrial ventilation fan to have a local isolator, so the guy changing the belt does not lose his arm when it starts under remote control, and applied that to a silly little bathroom fan.

 

[Murdoch]

The reference you mention is included in the Electrician's Guide To The Building Regulations (pg 65)

Thanks

But not many people have this!

I 'm never sure either to be honest .  I put 'em in to save any comebacks .;

One assessor picked my up on using a spur , outside the room ,  3A fuse , which isolated the downlights and the fan  ...ensuring the trigger wire was dead.   However he maintained that to work on the fan  you'd want the lights on so a spur was wrong and 3 pole  should be fitted .  

I expostulated   :C   that I managed to  install cables , fit down lights  & fan ....all without  the lights on  .. but that wasn't good enough ...it had to be a 3 pole isol. 

However  if I remember correctly he found fault with virtually everything  I'd done ........looked at a small swa I'd run  and decided that ..yes ...he'd have fitted one extra cleat to what I'd done .  

Even the lady customer commented after he'd left  that there was no pleasing that guy ... bet you'd like a cuppa after that lot .  

I'd be asking him for the reg number to back that up .................. then get my BYB book out.

The scams can't go around making up rules to suit themselves

 

[Evans Electric]

Murdo it was a 6 + 1/2 hour assessment  ...I' never wanted to see him again TBH   .         Mr  " Quoting Reg. numbers all day "  is NOT my bag I'm afraid .  

 

[Evans Electric]

Isn't there a reference somewhere about rooms with no windows and fan isolators (so that you can maintain a fan without turning off the circuit) 

I think it just comes in under local isolation .

There was a spate of coming across spur units that switched the L & N  to the timer fans but left the trigger wire  live .    Found quite a few myself , so I presume the 3 pole isolators appeared . 

Theres a recommendation  somewhere  for a local 3A fuse  so  a faulty fan doesn't take out the light circuit ....I don't think many bother with that.

 

[Murdoch]

Murdo it was a 6 + 1/2 hour assessment  ...I' never wanted to see him again TBH   .         Mr  " Quoting Reg. numbers all day "  is NOT my bag I'm afraid .  

You can ignore them if they make these stupid comments ............. it all gets difficult if the give you "improvements" to do before you pass - then I WOULD insist on them being very specific about which regs they think are contravened...

 

[SLIPSHOD & SLAPDASH]

As mentioned above, this has been discussed many times.

 The local isolator  is fitted due to the risk of injury by the mechanical movement  of the fan & not electric shock . This rule came about years  ago in relation to much bigger bits of kit than the puney 100mm bathroom fans that  could not do any damage even if you stuck your fingers in the rotating blades.

Saying that , we still always fit them to timer fans or 3 core wiring of fans.

Going back to the OP, for the reasons i stated above i have fitted a few bathroom fans with no timers and wired in 2 core & earth cable only direct to a pull cord or standard switch with no further isolator.

 

[mikep]

I take the lighting  loop feed for the bathroom to a 3a switched fuse spur then take the lights off of that then the extractor isolator switch, the fuse protects the fan and lights, some extractor manufacturers  say to wire them this way.