DIY Consumer Unit Change

[flameport]

I do wonder what brand the £300 man is using, and how many ways the board will have. I suspect there is a "Subject to T&C" next to it.

Subject to absolutely no other work required at all (which in reality never happens) - and when the faults are found, they will be charged at a separate high rate.

Or it will be £300 for the CU and installation only - testing and certificates etc. are charged for separately.

 

[First-time-buyer]

Supply is PME, therefore 10mm Earth was suitable at 16th Edition, and i assume from your answer that is acceptable.

I need to attain if the £300 just includes the installation of the new consumer unt, and the testing of the RCD etc. I would naturally assume that any other testing apart from the RCD trip times are extra.

 

[JohnW2]

I need to attain if the £300 just includes the installation of the new consumer unt, and the testing of the RCD etc. I would naturally assume that any other testing apart from the RCD trip times are extra.

That's part of the issue. Any competent CU change should include, at the least, testing of all the circuits connected to the CU - so if such testing is 'charged extra', then you are effectively being misled as regards what the totality of the cost of doing the job properly will be.

Of course, some of the people offering the sort of deal you're talking about may not have any intention (or even, necessarily, ability or equipment) to 'do the job properly' - they might be planning to just 'change the CU' and then run! ... and, don't forget, as has been said, that the work needs to be notified - either (at minimal cost) by a legitimate self-certifying electrician or by yourself (at considerable cost).

Kind Regards, John

 

[Taylortwocities]

Before installing a consumer unit, it is essential that all circuits are tested both for continuity and insulation resistance.
Any problems raised will need to be resolved before changing the unit, otherwise there is no point in making the change.

Example: shared neutral on two lighting circuits - will cause the RCDs in a new consumer unit to trip
Example: bad insulation resistance reading on circuit will cause RCD to trip
Example: lack of continuity on a ring final will mean that the (proposed) 32amp MCB will be too large for the circuit's wiring


etc……..

 

[First-time-buyer]

I hope the £300 guy does so before, otherwise that could be quite embarrasing when the RCD constantly trips.

One area which may or may not be borderline, is the 11 lighting points (inc bathroom fans) that are supplied in 1.0 mm T&E and are on a 5amp Wylex MCB.

I imagine with the introduction of Energy Saving bulbs we will be okay, but in the older days of 60-100w bulbs it would have been close. However, you could apply diversity as you would usually never have every light on, at one time.

Good news though, i have an old roll of 1.0mm T&E (Black & Red)...now if i could only find where the upstairs light are fed from..

 

[JohnW2]

One area which may or may not be borderline, is the 11 lighting points (inc bathroom fans) that are supplied in 1.0 mm T&E and are on a 5amp Wylex MCB. I imagine with the introduction of Energy Saving bulbs we will be okay, but in the older days of 60-100w bulbs it would have been close. However, you could apply diversity as you would usually never have every light on, at one time.

The guidelines, presumably written before the era of energy-saving lamps/bulbs, require a calculation on the basis of 100W per lighting point, but then allow a 66% diversity factor to be applied. Even without diversity, 11 x 100W lamps would be just about OK (4.78A at 230V), but with diversity there would be no problem at all (in terms of the MCB). 1mm² cable is fine, even if deeply buried in insulation.

However, many/most people would interpret current regulations as requiring lighting to be split into at least two circuits, protected by different RCDs - and it sounds as if you probably currently only have a single lighting circuit.

Kind Regards, John

 

[First-time-buyer]

Thats exactly it John,

An old 4-way Wylex board in a house which sold for £155,000 in 2006. Looks like the cash went elsewhere.

The board has 1x lighting (5A), 1x sockets (30A), 1x cooker (30A), 1x immersion heater (20A) wylex insertable MCB. I was impressed that the cooker socket has a double socket on it, and the hob/oven are plugged into a 13A extension lead, which the cable has been pass through the worktop. Unsure why they did not fit a double socket to the cooker outlet, and mark it up as "Oven Use Only".

The other extreme is the immersion heater, someone has removed the DP switch, and fitted a nice 13A single socket. In leiu, the immersion heater can be plugged in, or if required the power shower pump can be plugged in its place. Funny enough, there is a single socket the other side of the wall, so no idea why they did not fit a single RCD fuse spur (£12 max?) and hard wire the pump..

I have not even lifted the floor board yet... i guess more to come..

 

[OwainDIYer]

Just as well?

I'd hope you would set your sights higher than the "We replace old consumer units for £300" man out of the paper...

I do wonder what brand the £300 man is using, and how many ways the board will have.

I have 20 MCBs and 3 RCDs across two BG boards (separate board for off peak heating) which cost £122 between them; the meter tails and main earth wire cost £39 + VAT alone.

I think another £30 on trunking to tidy all the rubbish into.

(And a new pair of cutters after I vaporised the old ones.)

 

[First-time-buyer]

This consumer unit is in the corner base unit of a kitchen cupboard. Not exactly the best place to be. I will need to remove the worktop/base units to allow access as i certainly would not want to be working inside a cupboard.

Mrs FTB hates the kitchen tiles, so hopefully they will go out and back in without any hassle.

 

[kai]

B&Q are the cheapest place to buy Wylex Consumer units it seems, and are open long hours, unlike the inconvenient 9 till 5 Mon to Fri Hours a Wholesaler does. B&Q also include V.A.T. in the price, immediately making them twenty per cent cheaper than any Wholesaler, with no nonsense and Credit Checks required.

 

[First-time-buyer]

I have had a reply from the £300 guy.

£300 becomes £400 if the earthing needs sorted.

How much is 6mtrs of 10mm Earth, a box of clips and 2x earth clamps.. ~

 

[OwainDIYer]

I have had a reply from the £300 guy.

£300 becomes £400 if the earthing needs sorted.

How much is 6mtrs of 10mm Earth, a box of clips and 2x earth clamps.. ~

And a scrubby sponge and some CIF to polish the water pipe to nice and shiny before clamping it. Or is it just me that does that?

 

[RF Lighting]

I have had a reply from the £300 guy.

£300 becomes £400 if the earthing needs sorted.

How much is 6mtrs of 10mm Earth, a box of clips and 2x earth clamps.. ~

You forgot to add all his years of training and experience so he knows how to properly size the wire, and run it in neatly in the proper place and connect to the correct bit of pipe work, and ensure the resistance of the finished job is low enough.

Oh and his time to go to the wholesalers for the cable, and his diesel and motor, PL, and PI insurance, road tax, income tax, vat, accountant fees, holiday pay, sick pay, and I could go on and on.

The guys running a business and needs to earn a living after paying out all his business expenses. The likely hood is that yours will be the only job he'll be able to do for the day. He will be lucky to earn much more than £120 of actual profit from you. It's not exactly a brilliant wage.

 

[AndyPRK]

and run it in neatly in the proper place

Oh and his time to go to the wholesalers for the cable, and his diesel

You would think most decent electricians would carry the correct green/yellow cable and pipe clamps in the van!

£100 is quite a significant chunk compared with the original cost,
and I would imagine there are a fair few other extras

And would then all run it neatly ? Some, but not all.

 

[Adam_151]

Charging £100 as a standard fee for doing the main protective bonding doesn't seem too bad to me.

of course there will be some where both water and gas services are nearby, but there will also me a good few where it'll be a pig of a run involving floorboards up (after moving furniture and carpets), conduit drops outside in a hidden corner, etc