Fuse box replacement - what do they do?

Jamesyboyjim

Jamesyboyjim

Jamesyboyjim

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Hi all, we have recently bought our first home and have been going through the process of getting it up to scratch, a few people who have either done some work for us or have quoted or have mentioned how old the fuse box is, we have decided to get it changed so have a sparky coming out to do it beginning of October.

What exactly is the process? reason I ask is we have had a new boiler installed but it has run into an issue, the electrics in the airing cupboard that used to power the old immersion heater that was going to be used for the boiler appear to be dead. Our boiler installer insists when we get the new fuse box the electrician will make it live as part of the fuse box change and he'll come back and finish the boiler setup (haven't paid him yet)

Does this sound right or is a fuse box change literally a swap job? Or does the sparky have to figure out what is what and liven anything up I might need / take out anything redundant. My missus has arranged this or I would have asked him at the time.

Just worried now I'll have to pay extra to get electricity up to the airing cupboard even though there is wiring there.
 
I'm not an electrician so my terminology will be poor but essentially they drop the existing wiring from both sides (your house, mains) and put in a new box and reattach. This could have additional breakers for better isolation if required + additional RCD protection (depending on how old your existing one is).

When mine was done, my rings were broken out to allow for better isolation from memory. If the wire to the boiler runs to the unit and it just requires connecting then I can't imagine he will quibble much... you might find it was dropped when an additional circuit was added as you'd run out of room.
 
our plumber said it was live when he removed the old immersion so seems weird that its now dead. We did have an issue with one of the circuits in the house (accidentally tripped the 13a sockets touching two live wires with a screw driver, wasn't me who did it but a mistake only made once I'm sure!) but it should have been on a different circuit I would have thought. Is it possible that I've also tripped the power for the immersion somehow?
 
Should just be a swap job. Sparky will fit a new Consumer Unit, figure out what circuits you have and wire them up to appropriately sized MCBs (correct amperage). On a modern residential C/U, you normally have 2 RCDs, so he'll balance the load across the pair.

Can't recall what the test\certification requirement is when a new C/U is fitted - might be additional cost.
 
Jamesyboyjim said:
our plumber said it was live when he removed the old immersion so seems weird that its now dead. We did have an issue with one of the circuits in the house (accidentally tripped the 13a sockets touching two live wires with a screw driver, wasn't me who did it but a mistake only made once I'm sure!) but it should have been on a different circuit I would have thought. Is it possible that I've also tripped the power for the immersion somehow?
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I'm sure someone more electrically intelligent will be along soon but not sure how that would occur.

You have mains->CU->wire->socket, for something to be permanently damaged there has to either be an issue on your socket, the wiring or the consumer unit you'd have thought (breaker?). I'm sure there are cases of MCBs playing up but I'd suggest that unless you've got a fault on your wiring (ie, in wall, under floor) it will be a quick fix.
 
When I had my old tank with immersion heater removed and combi boiler installed, they used the same connection to power the combi that originally was used to power the immersion. 15A on it's own dedicated fuse in my old skool wire fuse box.
 
ZG002 said:
What type of board do you currently have?
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No idea on any actual model numbers. Something old and yellowed over time with little black switches and a big red one to do all the mains. Last serviced in 2008 and very very old. I cant find any images on google.

LeeUK said:
When I had my old tank with immersion heater removed and combi boiler installed, they used the same connection to power the combi that originally was used to power the immersion. 15A on it's own dedicated fuse in my old skool wire fuse box.
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Well that's what they were going to use but they couldn't get any life out of the socket when connecting the combi to it. The plumber said it was live when he removed the old immersion but not when he hooked up the combi. My missus stupidly said it might be our fault so now the plumber has said he'll do it when we get it sorted. She should have played dumb and said it should work, what have you done.
 
Could you grab a photo of those?

Sometimes if your immersion heater is up stairs they place a spur to control the outlet down stairs, It's just a thought is all.

He might of shorted out the feed at the immersion heater and popped a fuse else where which is why it's now dead.

Tbh it would be fairly easy to sort for the electrician, just mention you need a feed for new boiler.
 
ZG002 said:
Could you grab a photo of those?

Sometimes if your immersion heater is up stairs they place a spur to control the outlet down stairs, It's just a thought is all.

He might of shorted out the feed at the immersion heater and popped a fuse else where which is why it's now dead.

Tbh it would be fairly easy to sort for the electrician, just mention you need a feed for new boiler.
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thanks for your advice, I'll get some pictures tonight. I think its best as you say I mention this to the sparky before he comes so he can advise if its something he can do at the time, cost etc.
 
Well the sparky sorted it out, there was another switch that controlled the old immersion controls in the airing cupboard that has been cut off and the socket filled in :rolleyes:. He popped a few floorboards, found the cable and removed the old socket and bypassed from the circuit. Really pleased with his work and attitude to it actually, he went well above and beyond for me without charging extra. :)
 
Jamesyboyjim said:
I paid 450 for the fuse box replacement. He sorted out a few sockets / ran the earth to the mains pipe and did his tests / reports for the house as part of it.
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Similar to what I paid last November for the same work, was just sense checking the prices (as I can see you are in the South as well).
 
Peerzy said:
Similar to what I paid last November for the same work, was just sense checking the prices (as I can see you are in the South as well).
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Fair enough. To be honest it was technically 400 for the box and 50 to run the earth (about two metres) but if I tell myself I've paid someone £50 to run two metres of cable I'll lose my mind!
 
Anything around £400 is a reasonable price for a board change, expect to pay a bit more if extra work is required.

A fully loaded consumer unit costs £100 just to buy, there are bargains around every now and then though.

A sparky might come and change the board and it be a breeze, another house might be a total nightmare so generally a board change and test is at a set price with that in mind.

I would have expected the electrician to use the old immersion cable to power the new boiler. It makes sense as it is already at the board and can be isolated by the MCB.

To be honest a board change is relatively simple to do. The difficulty comes if the old board is very small and the wires have been cut very short and need to be crimped to fit the new board.

Usually when you want a board change and test you will get a proper electrician rather than some dumb **** general builder who thinks he knows what he's doing because he put a socket in a conservatory once.
 
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