Ring Main - old flat

covenantuk

covenantuk

covenantuk

Associate
Joined
23 Apr 2012
Posts
2,179
Location
Edinburgh
I have an old flat, built around 1910. A few days ago it managed to blow a fuse for the kitchen sockets.

On investigation, it seems that all the sockets in the house are on a 16A ring main, except for the front room which is on it's own 16A ring main. The cooker has it's own 32A fuse.

I'd budgeted for replacement of the old fuse box with a newer one using RCBs but I'm concerned about the kitchen ring main.

Is the wiring only likely to be able to cope with 16A? With a washing machine, dishwasher, kettle, fridge, freezer, toaster and coffee maker plus a computer, monitors and 3 x Sonos it's actually pretty easy to exceed 16A - I'm susprised this is the first time it's happened. When replacing the fuse box could I use a 32A RCB for that circuit?
 
Nope.

And I certainly wouldn't replace a 16a mcb with a 32a version.

What the overall condition of the wiring, without inspecting it myself, you need someone in to check it.
If it was my place, I would have total rewire.

Probably need more than a fuse box, to bring you up to 17th regs.
 
Last edited:
Ring main

1st of all are you sure it's a ring circuit and not 2 radials using the single protective device? Have you continuity between both line conductors /cpc/neutrals ?
Insulation tested for continued use?
Until you,ve tested the cabling I would,nt spend any cash on the board as they my need replacing .
 
Stinkyfingerz said:
1st of all are you sure it's a ring circuit and not 2 radials using the single protective device? Have you continuity between both line conductors /cpc/neutrals ?
Insulation tested for continued use?
Until you,ve tested the cabling I would,nt spend any cash on the board as they my need replacing .
Click to expand...

Also thought it more likely be a radial, but I have seen 16a ring mains many years ago, funny thing that was in Aberdeen.
 
Quite possible it's radial, hadn't occurred to me.

I really wanted to avoid rewiring as the kitchen is way down on the list of rooms that need refurbishment. We are however doing the hall and bedrooms so I'll get a quote to replace the fuse box and have those rooms rewired onto another circuit. That'll reduce the load a bit and I'll get them to run a new circuit as far as the kitchen door so that it's easy to rewire when we do eventually refurb that room.

Thanks guys
 
Have a full test on the wiring first, will tell you the overall condition of the electrics, then decide your next step, pointless replacing consumer unit if rest of electrics are in a poor state, plus a radial in modern kitchen is old fashion today, with the number of appliances in use in one, I think it's a bad idea to stick with it.

There a possible fire risk, earthing problems, plus any possible number other issues, better to completely rewire, if in a poor state, & it needs a lot of work to bring you up to 17th regs.

Better to have all the mess now, can't see the point of rewire part of house & decorating, only to have upheaval say a year or two's time.
 
Last edited:
Nightglow said:
Have a full test on the wiring first, before changing consumer unit.
Click to expand...

This.

It sounds like you have 2 x 16 A radial circuits and not a ring circuit.

Any minor earth faults on the wiring will cause nuisance tripping with a new mains board.

There are no easy fixes, a qualified electrician is your only option.
 
NEVER replace a fuse/mcb/rcbo with a higher rated one unless you know what you are doing and have verified that the cable it protects has a CSA that is capable of carrying that specific current.
Incorrect current protection at the CCU is a sure way to turn the copper cable in your house into a red hot heating element and burning your house down:p

16A ring FINALS are not standard practice and as others have stated it's more likely two radials sharing a fuse. Easy to check, isolate/turn off all circuits, disconnect one of the 16A cables at the CCU and if the dis-connected one remains live when the 16A circuit is re-energized it is indeed a non standard ring.
If the dis-connected cable is dead then it's 2 radials sharing a fuse (not recommended but perfectly safe)
 
You ideally need it to be looked at by a qualified electrician.

He'll be able to carry out a end to end test at any socket you wish and tell you weather it's a ring final circuit or not, or in fact a radial.

If it's old colour wiring (Red/Black,Red/Yellow/Blue) and your planning on re-newing, i'd get it rewired to have it right up-to-date and to current date regulations.
 
You must log in or register to reply here.
Back
Top Bottom