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I currently have two consumer units and there in a bit of a mess with wires going every where and no lables telling you what is what i want to get this replaced with just one unit i have night storage heaters so i think that one of the consumer units is for the econmy 7 supply is this right i'am not to sure do i have to get two new boxs or can they both be put into the the same unit.

Hi, as both supplies on different rates & 'nitestore' is only alive at certain times of day/night it needs seperate 'tails' to meter, you can get a combined unit but they are just 2 in 1 box so no advantage that I can see, & to change means apart from being part p'able most of the wiring won't reach as no 2 makes of consumer unit ever have the same layout, instead of tidying things up you could end up with loads of joint boxes to lengthen wires, as our transatlantic cousins say " if it ain't broke why fix it"
box it over, regards SPARX

thanks for the reply if i were to get these changed over to just one new unit what sort of price would a electrician charge me parts and labour just so i've got a ball park figure if i get some quote's

Expect around £450-£500 as dual rate con.unit not run of the mill item so expensive & is a long days work to do, plus test sheets, plus reg. for Part P
regards SPARX

That's alot more than i expected how much does a combined unit cost then and i take it that it would be cheaper to fit a seperate unit for each supply i'am planning on fitting a central heating system soon and there is not any spare room for the 45amp fuse i need for the boiler and also two seperate 16amp fuses for the water tank one 24 hour supply and one for the off peak supply.

Would 6mm be ok for the 45 amp feed and 1.5mm for the two 16 amp feeds.

Hi, can't find 'dual tariff board' listed in normal books which is how i Know it will be expensive! prob. at least £200.00
Altho' 1.5mm adaquate for immersions unless Very long run, most people still use 2.5mm, 1.5 good for 18.5 A, so away you go!
Presume boiler is Heatrae-Sadia/Amptec type @ around 10 kW?
tw/e pvc cables...6mm,'clipped direct' IE surface run =58A
" 6mm,'enclosed in wall' ie FLUSH =42A
10,000w/230V = 43.5A
9,000w/230V = 39.1A
More info = more info!....regards SPARX

Thanks for the reply the heater is a heatrae sadia electromax with a 9kw boiler at 37.5 amps for the central heating and two 3kw immersion heaters for the internal cylinders the manual states that all three should incorporate a isolating switch which i am going to put as close to the boiler as possible it says the two immersion heaters should be supplied by 1.5mm hofr cable from the switch's but it doesn't mention anything about the 6mm feed to the main boiler should i just run it into the switch and then run 6mm cable from the switch to the connections in the boiler by the way the run is about 7-10 meters from consumer units to boiler cupboard. also if i were to have two seperate consumer units what sort of price would i be looking at.

Hi agn.
I have never installed this set up but have read blurb abt it, you will need 45A double pole sw, as for showers, cookers etc & deepest box you can get to mount it on as 6mm not very flex. don't know abt cable to main heater but would imagine it comes with a short length of suitable heat resistant cable fitted.
Immersions will need two fused spurs wired one from each mains consumer unit, the hofr is heat resistant flex agn. sold by the meter for the purpose, made of butyl rubber, usually white (& gets dirty very easily
)
Standard con. unit with MCB's between £45.00 & £100.00 each depending on how large, RCD fitted etc, Leckie should charge around £200/day-£30/Hr. plus cost of certs, registering work, (on line to approving body/bldg cont) plus any other bits he might use