Lightswitch Wiring Help - 3 gang to 2 gang

[D J Fryer]

Have saved all the pics and instructions from that post breezer.

The survey on the house (and the electrician who was appointed by the people who did our kitchen) said that although the CU is not completely up to date (no circuit breakers/trips - just big pull out fuses) the wiring from the CU is 'up to date'. Even to my eyes the wiring from the CU looks incredibly new. This makes me wonder at what point from the CU the wiring ceases to be like this and changes to the old hideousness I discovered yesterday evening on the lounge light switch?

In your experience could it be that the wiring from the CU for this lighting circuit is okay up to the point of the first ceiling rose/junction box and then the old stuff has been left down to the switches? Could this be because the wiring is buried in old metal cylindrical piping buried in the walls and this is difficult to replace without chasing out etc? I would imagine that this sort of trunking would have been used so that wiring could be 'pulled through' but maybe the reality is very different?

I do appreciate the advice provided, I have used the search function for most of the queries and found useful advice that way but the specific replies given are extremely helpful so thank you.

 

[breezer]

the old cylindrical piping as you call it is called conduit, it is actually installed first then wired afterwards.

trouble is it does sound like it too is old, new conduit is 20mm old conduit is 3/4 of an inch

it is possible that who ever owned the house willingly or unknowingly had "the bits you can see" changed.

to be honest it really needs to be looked at, ie taken apart (see how it works*)

if you can a few pictures would help, but from what you have sid it does sound like re wire time

* joke

 

[D J Fryer]

Thanks for your candour, it is appreciated. Considering that there are only 3 sockets and 2 lights downstairs on the old CU and 3 sockets and 5 lights upstairs it might not be a huge job [he says in the hope of the cost not being too high!].

I'll take a couple of pics this evening so you can see what I mean (more out of interest than anything else). I think that whilst the house is being done it may be easier to get someone in who can do it all in one hit.

 

[ban-all-sheds]

I think that whilst the house is being done it may be easier to get someone in who can do it all in one hit.

Never a truer word spoken, particularly if there's any chance that chasing channels and sinking boxes will be required - that makes a mess.

And with that few sockets in the rest of the house, it sounds like this might be the case.

 

[D J Fryer]

I'll post some pics tonight for your amusement of how much this is all going to cost me

 

[securespark]

Could it be the CU has been moved slightly, necessitating extending the cables? This will explain new cables in CU, but possibly has JB's connecting to old cable under floor?

 

[plugwash]

i have hearede it reported at least once that rewires have been deliberately faked

 

[D J Fryer]

Well here's some pics of the offending so to speak: -

What started it all - The Lounge Light Switch

Then The Lounge Wall Light

The Consumer Unit - with the new one on the right for the Kitchen/Diner

The old CU a bit closer - only one fuse does both upstairs and downstairs lighting (as I worked out earlier)

Hall 2 -way Light Switch

Hall Socket

I reduced the images substantially so hopefully they don't take too long to appear - sorry to all 56k slowdem users.

I seriously hope this has not been 'faked' - lady we bought from was in her late eighties and lived here from when it was built in the fifties and IIRC her son-in-law was a sparky. Would a 'professional' do this just so that it did not stand out on an intermediate mortgage survey

 

[ban-all-sheds]

I seriously hope this has not been 'faked' - lady we bought from was in her late eighties and lived here from when it was built in the fifties and IIRC her son-in-law was a sparky. Would a 'professional' do this just so that it did not stand out on an intermediate mortgage survey

Sadly, yes, there are some who would do that. Anyway - just because he's described as a "sparky" doesn't mean he's a pro, except in the sense of getting paid for it. Have you found any evidence of new wiring behind any accessories?

1) I note that there's an earth connected to the wall light. I wonder where it goes?

2) Just curious - where does the earth wire leaving the fusebox with that bunch of cables go?

3) What's the rating of the shower that's on that 30A fuse? Is it 4mm cable?

4) What's the RH 5A fuse for, the one with the label that used to say "Sockets"?

5) A right mish-mash of cable and flex in the hall switch, and is that a wire-nut that I see top-left?

6) Hall socket. No earth? Or is it supposed to come via the conduit? Looks like 4mm cable, so are your socket circuits radials? And, looking back at the fusebox, have you got two radials on one fuse?

 

[plugwash]

no rcds in sight either

meter tails look ok

personally i would swap the isolator in the new CU for a rcd and put all sockets and the shower on the new CU and all lights and the water heater on the old CU (using plug in mcbs in place of the rewireable fuses)

the only issue swapping the isolator for a rcd would require isolation before the CUs

if the rec have been nice enough to provide an isolator in the meter box this is easy

if not someone will have to pull the service fuse and many sparkys here advise againt siyers doing this (sparkys do it all the time)

earthing via conduit was considered acceptable at one stage though i would not trust it myself

and the actual wire connection to all that kit those sockets looks dodgy too

 

[breezer]

what looks like rubber cable for the wall light

all i can say is marvelous

 

[D J Fryer]

Have you found any evidence of new wiring behind any accessories?

Nope.

1) I note that there's an earth connected to the wall light. I wonder where it goes?

I thought the same

2) Just curious - where does the earth wire leaving the fusebox with that bunch of cables go?

Not sure - would have to lift some floor boards and find out

3) What's the rating of the shower that's on that 30A fuse? Is it 4mm cable?

Used to have an electric shower - this was replaced with a power shower (Monsoon pump) Dec last year when bathroom was re-done by a local chap. Not sure whether anything is on this now.......? The labelling isn't all that clear cos we don't have a water heater anywhere in the house.

4) What's the RH 5A fuse for, the one with the label that used to say "Sockets"?

Not sure

5) A right mish-mash of cable and flex in the hall switch, and is that a wire-nut that I see top-left?

Top left - if that's what one is called then perhaps ?- it kind of looks like a ceramic thing joing the wire together.

6) Hall socket. No earth? Or is it supposed to come via the conduit? Looks like 4mm cable, so are your socket circuits radials? And, looking back at the fusebox, have you got two radials on one fuse?

Pass - I am not qualified to say I understand what you mean by radials (thank you the 'for reference' thread) but would not have a clue whether these sockets were or not unless I could easily trace the wiring.

 

[D J Fryer]

no rcds in sight either

meter tails look ok

personally i would swap the isolator in the new CU for a rcd and put all sockets and the shower on the new CU and all lights and the water heater on the old CU (using plug in mcbs in place of the rewireable fuses)

the only issue swapping the isolator for a rcd would require isolation before the CUs

if the rec have been nice enough to provide an isolator in the meter box this is easy

if not someone will have to pull the service fuse and many sparkys here advise againt siyers doing this (sparkys do it all the time)

earthing via conduit was considered acceptable at one stage though i would not trust it myself

and the actual wire connection to all that kit those sockets looks dodgy too

Not all bad then

Seriously a lot of that post went over my head but it is appreciated nonetheless. Looks like getting a professional in will be the best thing.

 

[D J Fryer]

what looks like rubber cable for the wall light

all i can say is marvelous

Even I know that rubber on wiring = not good. Oh well time to extend that flexible mortgage arrangement............again!

 

[plugwash]

some sparkys may hate me for suggesting this

but once you get rcd issue sorted out (either by putting a rcd in the new board and using that board for all cuircuits needing rcd or by replaceing both CUs with a modern split board) the rest of a rewire job should be easy

there are 3 types of cuircuit you are likely to wan't to install
ring cuircuits : 2.5mm cable wired from a 32A breaker in a ring and back to the CU maximum length of ring is just over 50m iirc

ligting cuircuits: 1.0mm or 1.5mm cable from a 6A breaker
max length just over 30m for 1.0mm and just over 50m for 1.5mm

dedicated appliance cuircuits cable and breaker sized to suit

the other thing thats bad practice there is you have a MET but not all your earthing is connected through it from the pictures it seems your main earth visits the wylex CU first an earth leves that with a bunch of cables (presumablly to the water pipes) and another earth leaces it going to a main earth terminal which then leads to the gas pipsing and to the new CU

i would replace that main earth terminal (which appears to be 4 way) with a new 8 way one (my fitting a showe CU post in the for refernce setion has a link if you are having trouble getting one) and move the incomeing earth and the bond heading off to the water pipes to it