Old consumer unit , - what are my options to upgrade?

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Just bought an old house. It has old wiring (red and black wires) and has an old and small consumer unit (the old black ones)

I want a new consumer unit with extra slots for expansion and potential rewiring. I will be installing an electric shower

Would really like to rewire the whole house, but cant afford to do that at the moment. So can I get a sparkly in to just replace the old consumer unit whilst leaving the old wiring in place? Then I'd install the shower myself using one of the free slots in the new consumer unit

Also any recommendations for a decent consumer unit? (4 beds, 2 bathrooms, 3 living rooms, garage, kitchen, security lights)
 
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Jim is that you??

:ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO:

Andy
You've said that about 10 times! Will you stop following me if I say yes I am Jim?

OK, yes you are right I am Jim. Hope you're satisfied now and we can stick to the topic.. Apologies, but every time someone replies I get an alert.. not really interested in these kinds of messages
 
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Personally I would go for all RCBO with an older property so if there are issues with a circuit, only that circuit is affected. As to make it would depend on the supply type, there are single slot duel pole RCBO's that can be used with TT supplies, but only with the more expensive makes. The problem with more expensive makes is the SPD also becomes more expensive, so total cost really goes up. Fusebox and British General (BG) seem to make reasonable boxes if you don't need twin pole switching.

The other problem is getting type A RCBO's, I know Fusebox and BG do a type A, but Screwfix does not it seems stock the type A, CEF lists a type A at £23.94 but type AC in Screwfix down to £11.99. The same with FuseBox the type AC rather cheap, but type A more expensive.

I made a mistake with my own house, I saw type B written on the box and thought Oh good did not expect type B but in fact it was curve B type AC and did not realise until after the electrician had fitted them all.

So if you want type A there is not so much of a saving using the cheaper boxes, as to if we really need type A not so sure, I ordered up type A for my ring finals, but due to Colvid I suspect they never arrived at retailers so cancelled. And I am using all type AC. If I go for an EV will have no option but change to type A, but not convinced really required.

If not going down the RCBO route, then be aware all RCD's are not equal. The spec says between 15 and 30 mA they must trip and at 5 times trip in 40 mS, but some makes don't say 50% to 100% but 90% to 100% like the X-Pole and also have a warning when approaching the trip point. We should test first, I have a insulation tester so no problem testing the insulation, but that is DC, what we really want is the actual leakage current, so a clamp on ammeter with a 0.001 increment scale, multi circuits should not exceed 9 mA in the main the loop impedance meter uses around 6 mA with no trip test, but it was enough that in my old house I could not use the loop impedance meter on one RCD, yet the 50% no trip with RCD tester passed.

What you want is for the RCD to protect but not nuisance trip, and to be sure really need to test existing installation first, that's why I went all RCBO in last house I would get a bout of trips with no fault found, then years with no trip. Fitted in around 1992 I would say lost around 3 freezers full of food, so feel safer with RCBO's. No longer permitted auto reset types in domestic.

So you in some ways you get what you pay for, in theory a consumer unit is a type tested distribution unit and to keep the type testing you can only fit devices recommended by the manufacturer, so can't fit a BG RCBO in a Wylex consumer unit even if they will physically fit. I have seen it done many times, and with an EICR only code C1, C2, and FI is a fail, and it would be hard to say wrong make is potentially dangerous.

I fitted an external isolator and had to extend cables for some circuits, and fitted a fusebox make which cost around £250 for materials but included wire, crimp pliers, and other bits, and I have 14 RCBO's fitted. When I got a leak I was glad I could simply switch off some sections without effecting others, had I used MCB's I would have had to drop tails to stop neutral to earth faults.

I am not saying what to do, just giving food for thought.
 
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Just bought an old house. It has old wiring (red and black wires) and has an old and small consumer unit (the old black ones)

I want a new consumer unit with extra slots for expansion and potential rewiring. I will be installing an electric shower

Would really like to rewire the whole house, but cant afford to do that at the moment. So can I get a sparkly in to just replace the old consumer unit whilst leaving the old wiring in place? Then I'd install the shower myself using one of the free slots in the new consumer unit

Also any recommendations for a decent consumer unit? (4 beds, 2 bathrooms, 3 living rooms, garage, kitchen, security lights)
Yes you can replace a CU on old wiring, but it should be tested first. Let the sparks choose the CU.

You cannot install a shower yourself without notification and testing and paying highly for the privilege as it would be a new circuit.
Are you sure you want an electric shower? Electricity is 4 times the cost of gas if you have gas available?
 
providing the wiring is safe, then yes a spark could change the CU.
The bonding to water and gas will need updating.
If the lighting circuits don't have an earth, a warning label will require adding to CU

Yes go for a large box, with RCBOs
 
Yes you can replace a CU on old wiring, but it should be tested first. Let the sparks choose the CU.

You cannot install a shower yourself without notification and testing and paying highly for the privilege as it would be a new circuit.
Are you sure you want an electric shower? Electricity is 4 times the cost of gas if you have gas available?
it would a backup shower in a second bathroom - hardly ever used and would come in handy if the boiler's not working
 
it would a backup shower in a second bathroom - hardly ever used and would come in handy if the boiler's not working
OK but this still applies:

You cannot install a shower yourself without notification and testing and paying highly for the privilege as it would be a new circuit.
 
btw any idea on ball-park labour cost for replacing a CU to a more modern one. Assume that all the testing is OK

There are earth terminals in the lighting circuits and the wiring in the house is a combination of modern and old.
 
OK but this still applies:

You cannot install a shower yourself without notification and testing and paying highly for the privilege as it would be a new circuit.
Thanks, didn't know that a sparky had install a shower circuit. Will be done down the line and will get an electrician to wire it up
 
What part of the country are you in.

If you were to agree with the spark before hand, maybe you could lift up a few floor boards, to make it easier/cheaper for him to run the cable in to the shower and connect up. (install shower and water first)
It's probably cheaper in the long run.

New circuits have different rules
 
What part of the country are you in.

If you were to agree with the spark before hand, maybe you could lift up a few floor boards, to make it easier/cheaper for him to run the cable in to the shower and connect up. (install shower and water first)
It's probably cheaper in the long run.

New circuits have different rules
Good idea, will discuss with the spark who changes the CU

I'm in Boston (East Midlands) - now whats the best way to find a decent sparky? Shall I just use the yellow pages? I dont live there and am not from the area so don't know anyone
 
now whats the best way to find a decent sparky? Shall I just use the yellow pages?
NO!!!
You will need a registered and competent electrician. That gets you someone who has been accredited and is able to self-certify and notify the work (new circuits and a change of consumer unit is notifiable works.)

Avoid Yellow Pages, MyBuilder, Checkatrade, and all those so-called trusted trader lists. The only qualification you need to get on there is for the trader to pay some ££££ (and get their sister to invent a recommendation).

There is only one (independent) place to look

https://www.electricalcompetentperson.co.uk/

Get several quotes and , if you can, ask neighbours for a recommendation too. But the person doing the work MUST BE REGISTERED.
 
I have to agree with @Taylortwocities avoid MyBuilder, Cheakatrade and the like, if the electrician is any good he will not waste money paying for them to advertise for him. In the past I would ask in the Pub, but today most whole sale outlets will help you find a tradesman linked to what they sell.
 
a few pics you may find interesting

p1.jpg
p2.jpg
PXL_20210531_175426291.jpg
 

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