Spur at Boiler?

[Jake123]

Hi there,

I am an electrician working in the west of Scotland, The company I work for does a wide range of work, however central heating is a dark area for me, we do inspection, testing commercial and industrial but when it comes to central heating I am not up to speed.

I have been asked to install a switched fused spur for an existing old boiler in a domestic house, the landlord checks has picked up that there currently is not one there.
I know there has to be a switched fused spur next to a boiler for maintenance purposes to isolate the boiler. When I opened up the boiler there I was expecting a Live, Neutral and Earth, and to redirect this mains into a switched fused spur and from there back into the boilers mains connections with 3 core butyl, however there is a switched live, permanent live, neutral and earth in the boiler with the existing butyl (4core) disappearing down the cavity.

Can anyone help with the best way to carry this out? As I say all other aspects of works I am quite clued up on but heating I dont really have a clue,

thanks for any help

 

[Guest123]

Sounds like there may be a wiring centre somewhere, in the airing cupboard perhaps.

If there is a fused spur there with the correct fuse in it, you could install a triple pole isolator by the boiler.

 

[ezzzekiel]

the l/n/e in the boiler needs to be interupted by the spur but as lenny states this may be fed from a wiring centre first so trace the feed and run it through the fcu first.

would imagine 3 core coming from wiring centre into boiler so find wiring centre and put fcu before its feed, if not local possibly above often find them in loft from earlier heating systems and reused.

 

[Doomed]

As above, there will be a wiring centre somewhere. Check that this has a fuse protecting it (normally 3A in a domestic setup, but check the system requirements as I have had some older systems needing 5A).
Then install a triple pole switch by the boiler to allow for isolation for maintenance (L/N/SL). A fan isolation switch will do the job nicely as long as it is rated for the same value as the protecting fuse.
Don't switch the CPC as I have seen done in the past.......