Using an FCU for lighting

[srrray]

I have just had a combi boiler installed, ripped the old hot water cylinder out of the airing cupboard, and removed the airing cupboard so as to enlarge the bathroom.

The FCU to which the emersion heater was once connected is now open to the bathroom (in Zone 3). I have built some shelving units in this area with a downlighter planned to be installed, and thought I could power it from the FCU. Is this possible?

If so, there is no earth cable evident at the FCU and I wondered if this would be a problem once I've purchased the downlighter.?

The cabling to the FCU is truncated through metal tubing that runs under the concrete floor, and is chased into the wall.

How is the FCU earthed (if it's supposed to be)? Can anyone see any complications?

 

[industryspark]

srrray wrote;

there is no earth cable evident at the FCU

what is the type of cable running in the trunking? twin and earth? singles?
the fcu should be earthed yes. im thinking the metal conduit is the earth. or is it old cable? earth cut back into the cable?

to be honest i would say that this doesnt sound like a big job so why not get a spark in to do it? make sure he's a registered one (to a scheme).

i say this as DIY electrics in the 'bathroom' (as the fcu is now in) is always i think a bit of a no no with it being a special location. the spark would also test the integrity of the earth at the fcu (if you have one!) and would be able to advise.

 

[srrray]

Hi Industryspark,

Thanks for your interest. The cables are single, one live, one neutral. No sheathing. No earth. The same pattern runs throughout the flat for all sockets.

I, like you, was thinking that the metal conduit was earth. Is this a usual thing of the past? These flats were built in 1964.

 

[securespark]

It's usual with conduit to use the metalwork as a cpc (earth).

 

[srrray]

It's been some time since I first raised this topic. I've been suffering an illness for the last six weeks so I never got round to the subject again, and still haven't completed the work. However, now I'm fighting fit again and want to get this work finished this weekend.

The metal conduit and mounting box are channeled into the wall behind the new framework that I have built. The framework will be boarded and tiled, and I want to move the FCU forward into the tiled wall. I was planning on fitting a new mounting box onto the framework to take the FCU.

My main concern regards the earthing of the new mounting box. I am assuming that the best way would be to run an earth cable between the old and new mounting boxes (or a metal 'strap').

Is the the correct way of going about this?

Cheers.