Fan isolation

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I took an assessor   ( one of the more pedantic ones )    to a  ground floor  extension , creating a wash & shower room,  and bedroom for a disabled child .   Plus kitchen extension.

The shower room , quite big ,  was a bit dark  .....I'd fitted downlights  , linked to the fan with a light switch  outside in the corridor and a spur  that killed the lighting /fan.    

The 3 pole isolators were just becoming known at the time .

This guy was so pedantic , we were there from  lunchtime till about 5.30  after 2 hours in the office.     ( How long does it take to look at a regs book & some insurance docs.)

He homed in on the spur ,saying if it's off theres no light in the room ,  I said well  the builder & I  managed to  install electrics , plaster , tile , fit , all plumbing , fit toilet , shower , basin  ,  floor tiling , mirror, door etc  ..... by plugging in a stand up fluorescent light :C

But no ...the maintenance & cleaning of the fan  was of paramount importance    ( Like  every 10 years    :C )      Just to prove his point and I should be adopting 3 pole switches. 

The extension had a loft hatch  and I'd cross bonded the plumbing up there ....didn't like that much  .

I think because of my comments we had to have EVERY  light down , every switch off , every socket off ,  outside lights dropped off and a ALL my tests redone and compared to the test sheet .  

 
I would say  afan even with a pull cord is still a fan - the isolator isn't there to operate the fan, it's to isolate it for maintenance. If a lamp fails in a light, you are in the dark anyway.

 
I would say  afan even with a pull cord is still a fan - the isolator isn't there to operate the fan, it's to isolate it for maintenance. If a lamp fails in a light, you are in the dark anyway.
So if we need an isolator for a poxy bathroom fan, surely we also need an isolator next to each light fitting so we can maintain them ?

Nobody has yet quoted what reg or law says a bathroom fan must have an isolator.  It is turning onto one of those urban myths that we "must do it" but nobody has ever seen the rule that says we must.

 
So if we need an isolator for a poxy bathroom fan, surely we also need an isolator next to each light fitting so we can maintain them ?

Nobody has yet quoted what reg or law says a bathroom fan must have an isolator.  It is turning onto one of those urban myths that we "must do it" but nobody has ever seen the rule that says we must.


you will also need an isolaor next to the isolator so you can do any maintenance on the isolator

 
I think an isolator is a good idea for when the cheap, Chineseium POS spontaneously combusts you can stop your house from burning down.

Providing that you are at home to turn it off!

Perhaps the AFDD things are to compensate for a lack of quality standards in the appliance manufacturing industry?

 
I think the most compelling argument for an isolator is so that it can be switched off during the night, so it doesn't drone on for 20 minutes after you've had a number 1

 
In my opinion a means of isolation for a domestic fan has nothing to do with a competent person coming back later to repair, swap, or maintain it in any way. It is to allow a non skilled ordinary person to carry out the routine cleaning maintenance recommended in the manufactures instructions. I don't recall seeing any fans where in the small print they don't suggest removing the cover and cleaning the small plastic blades at regular intervals to prevent the build up of dust, dirt, grease etc that can clog the mechanism and reduce the air flow efficiency. The fact the 99% of homeowners probably never do this recommended maintenance is no reason not to provide an easy means to isolate the power, without having to used torches or candles to see what they are doing, whilst they undertake this task it if the so wish.

Industry standard guidance has always been something along the lines of this Vent-Axia instruction;  "after ensuring that the fan is safely isolated from the mains supply, periodically check the fan is free of any dust/dirt/grease build up using a damp cloth with warm water and a mild detergent."   https://www.vent-axia.com/faq/how-do-i-clean-my-fan  The other key reason would be should the fan ever start continually running (timer circuit gone faulty), or smoke starts escaping from the fan, the customer should have an easy point to turn it off without losing the lighting circuit to the whole floor. If you are waiting around for someone to quote a BS7671 regulation to say you must fit one,  you will have a very long wait,  you are more likely to see a flock of flying unicorns land in your garden. But it is all down to the installers judgement and application of common sense and the specific requirements of the customer? 

Doc H

 
a customer of mine likes 2 light switches for the bathroom, 1 for night times that doesn't trigger the fam and just turns on a single fairly dull light. 




With bathroom updates I suggest the fan & light above the shower are on 1 switch and the remaining lights are on another ............ that's what I have done at home too

 
is to allow a non skilled ordinary person to carry out the routine cleaning maintenance recommended in the manufactures instructions.
I agree  Doc ..... but in my experience  the average , non sparky type people  have no idea what spurs & isolators are for .    I 've met folk  who asked me what that big switch is for by the cooker.    I've given up thinking  " is it not obvious?"    Then I wonder why did you never switch off to see what didn't work .    Then you get the  "  Oh I never touch electric "   

I think most Sparks are like myself ,  we suffer from ...." I wonder how that works then ?"   syndrome ,  but many people are totally lost with practical stuff like  where is the main water valve  ....How would I switch off ALL the electric  /Gas  .

My first neighbours , years ago , both teachers with 5 kids ,    asked my to put up some  bookshelves .  I said OK  or you could borrow my SDS  drill  .   NO no he says ,  I just cannot do anything like that to save my life .  Head of Maths at local comp. 

But great at other stuff like  chemistry in the garden ,  nearly blew the fence down  with his gunpowder experiment ......  all the kids  in the garden at night with a couple of decent telescopes  , looking at Saturn etc  .

On a job in a "Posh " house  , "Posh " area  ages back ,    the guy  asks my mate if we could disconnect the washing M/c  pipes while we were there.    He takes a look , I hear him say   " If you just turn that screw slot  in the ball o fix  you can always just undo the  two pipes  easily .  "  

 Posh voice:-       "Well I don't think we have any tools here"      Calls to wife .      " Darling !!!   Do we have any toooels  in the house?"   

Posh wife :-          " Toooels  ?   Tooooels !!    I don't think so Dear ....why would we want Tooooels ?"  :C

A family with a gardener  & a cleaning team  that came twice a week and a nanny .

Another lot , posh area ,  moved in , got us there replacing lights ,  had a perfectly clean , modern built in oven & hob replaced  and all the toilets  .   " Hime  not sitting hon those  or cooking in that thing !!"        Bloody oven was immaculate .     We took them away  and a month later gave them to a   young couple  in a flat with bugger all  .

 
With bathroom updates I suggest the fan & light above the shower are on 1 switch and the remaining lights are on another ............ that's what I have done at home too
That sounds good.

Bit like us  on the  houses round here  , always wired the hall 2 way/ 2gang   on the upstairs circuit  to save getting a separate  neutral  up to the loft .  

 
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I agree  Doc ..... but in my experience  the average , non sparky type people  have no idea what spurs & isolators are for .   


The customers ability is irrelevant, we can all recount stories of thick customers who cannot even swap a light bulb, but the competence of the person using an installation is not the fundamental reasoning for fitting an isolator or not. Common sense says if you have not fitted an isolator, a dumb or intelligent customer can never use one even if they tried to locate and use it. But if there is an isolator fitted, then anyone with enough brain-cells to utilise its function can at least make use of it to do the recommend safe cleaning detailed in the fans instructions.

Doc H.

 
That sounds good.

Bit like us  on the  houses round here  , always wired the hall 2 way/ 2gang   on the upstairs circuit  to save getting a separate  neutral  up to the loft .  




Hum ............. neutrals to switches ............ hall downstairs, landing upstairs ........... easy peasy............ job done

 
a customer of mine likes 2 light switches for the bathroom, 1 for night times that doesn't trigger the fam and just turns on a single fairly dull light. 
In my own house I had 2 switches side by side, one for the light only, and one for the fan only. FAR better solution. No isolator needed there.

But as I have said before, in  a rental, you must have a fan that cannot be disabled, otherwise it will NEVER run (and the tenant will be complaining about the damp and mould and the landlord will be described as a rogue for allowing such a damp house to be let) 

In my opinion a means of isolation for a domestic fan has nothing to do with a competent person coming back later to repair, swap, or maintain it in any way. It is to allow a non skilled ordinary person to carry out the routine cleaning maintenance recommended in the manufactures instructions. I don't recall seeing any fans where in the small print they don't suggest removing the cover and cleaning the small plastic blades at regular intervals to prevent the build up of dust, dirt, grease etc that can clog the mechanism and reduce the air flow efficiency. The fact the 99% of homeowners probably never do this recommended maintenance is no reason not to provide an easy means to isolate the power, without having to used torches or candles to see what they are doing, whilst they undertake this task it if the so wish.

Industry standard guidance has always been something along the lines of this Vent-Axia instruction;  "after ensuring that the fan is safely isolated from the mains supply, periodically check the fan is free of any dust/dirt/grease build up using a damp cloth with warm water and a mild detergent."   https://www.vent-axia.com/faq/how-do-i-clean-my-fan  The other key reason would be should the fan ever start continually running (timer circuit gone faulty), or smoke starts escaping from the fan, the customer should have an easy point to turn it off without losing the lighting circuit to the whole floor. If you are waiting around for someone to quote a BS7671 regulation to say you must fit one,  you will have a very long wait,  you are more likely to see a flock of flying unicorns land in your garden. But it is all down to the installers judgement and application of common sense and the specific requirements of the customer? 

Doc H
Thank you. First plausible reason anyone has given for why they are fitted.

 
I just ask the customer what they want...….

Give the pro's and con's of each option....

Then just fit what the customer wants to pay me for!!!

It is NEVER wise to try and fit anything the customer hasn't asked for...

They may refuse to pay if you choose to do work they don't agree with!!

:popcorn

Domestic....  Rental....  Commercial  etc..  are all very different beasts as to what is the best solution in my opinion!

So a ONE SIZE FITS ALL is never going to work!

:C

 
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