Do I need a new consumer unit ?

[fasea]

Hi,

I am intending to extend my lightting circuit into our conservatory at some point this year. I already asked for advice on this here .

However something I forgot to mention is that my house has an old style consumer unit (wylex I believe) which has wire based fuses rather than MCB's and definelty no RCD protection.

So my question is do I need to replace my consumer unit for a new RCD / MCB one before I attempt to extend my lighting circuit ? Or is my current one adequate enough. My concern is that I believe under part P I am allowed to extend an exisiting circuit (as long as not in a special location) but as long as the circuit has adequate protection ? and I'm not sure what that implies.

Also is there any benefit in keeping my current CU and just replacing the plug in fuses for MCB based one's ? or is this a waste of money and a new CU is the way forward ?

Any advice appreciated.

Cheers

Andy

 

[JohnD]

Some extra info that will help:

What colour is the Wylex; does it say what is the max Amperage on the main switch; does it have any spare fuseways?; have you ever had fuses blow; do you have old (or young) or technically inept people in the house; do you have any outdoor electricity; do you have any RCDs?

Do you know how old the electrical installation is?

Sooner or later you will have to have it replaced (and this is best done by a qualified electrician who is a member of a self-certification scheme). Is now a worse or better time for you than next year will be?

 

[fasea]

Hi,

Thanks for the quick reply. Here is the info that I have.

The Wylex is a creme / white colour looks very much like :

But I believe mine is 60W (but would have to double check). We have 2 spare fuses not in use, currently there is 1 for ring main (upstairs and downstairs) one for light circuit (upstairs and downstairs) 1 for cooker and one for doorbell

House was built in early 1980's I believe and I doubt the electrics have changed, only me and the missus in the house so no old people and we have no outside sockets, just a fused double socket in the conservatory and also a light running from this fused connection which I intend to remove.

I definetly will get someone to replace the CU but as we moved in this year and we have a few other things we want to get done I would rather wait until next year if we could just as we have limited cash at the moment. Though If this is a prerequisite to getting the new lights in the conservatory then I will have to get it done.

Thanks again

 

[JohnD]

OK, then. You haven't got an immersion heater or any storage heaters or an electric shower. Your cables will be PVC. I am assuming you haven't got a big range cooker or one with multiple electric ovens. Your installation will be somewhat out of date but I'm not hearing indications that it needs changing urgently.

I would suggest you get a couple of RCD Sockets and put them nearest to your front and back doors, where they are likely to be used for equipment out of doors (gardening or vacuuming the car). It is possible to get a Wylex add-on RCD kit, but it is not a very elegant solution and rather expensive.

You can get by with rewirable fuses; they are not approved of much because (1) in the event of frequent trips people put thick wire in them (2) it takes time and dexterity to change the wire. But if you aren't getting blowing fuses that's not a priority either.

When you do have a new CU fitted, the whole installation will need to be tested, and if necessary rectified, so it will cost you some hundreds of pounds. Buying the necessary test equipment, learning how to use it, and getting the Building Control to approve your work means that a DIY installation is more trouble and expense than having it done professionally. I am sure you will also want to have separate upstairs and downstairs rings, and lighting circuits; and RCD protection on the rings, preferably with RCBOs, else with a split-load.

You might like to look at your main and supplementary earth bonding arrangements already as they are probably out of date now, and this is something you can easily do yourself.

As ever, to get a better opinion, you could have a PIR done, on a fee-paying basis (not a "free" survey by someone who will use it as a marketing aid).