Discuss Wiring Heatrae Sadia Elextromax (6kW/9kW) in the Electrical Forum area at ElectriciansForums.net

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Regular EF Member
North East
We will shortly be wiring an installation which we have suddenly been told will be all electric, using electromax 6kw & 9kw boilers.
Looking through the instructions, connections as follows
Suitable MCB / circuit (32A / 45A) for CH
16A top immersion (booster)
16A bottom immersion- fed from the off peak supply.

Installation manual states
'Off Peak supply connection[FONT=Arial,Arial][FONT=Arial,Arial]
A suitable electrical connection must be taken from the Off Peak supply to the Electromax terminal block. '

These units are intended to be used on an economy 10 tariff. I thought that on economy 10, your offpeak hours counted
for ALL your load, - i.e. everything is on one set of tails- i.e. there is no 'off peak' consumer unit.

Am I mistaken in thinking that I can have one consumer unit, with the boost immersion on one circuit, and the lower immersion (powered from the same consumer unit / set of tails) on another circuit fed via a timer set to operate in correspondance with the economy 10 tariff cheap rate times?

ALSO, if anyone has had much experience with these. The larger (9kW) boilers will be sited in two bed flats.
Can anyone see a problem with the following:
There will be two lighting circuits, two 32A rings, 9kW shower & 9kW boiler but with relay installed so that they can not operate simultaneously, standard 4 ring hob, TWO x 3kW immersions- any problem on an 80A supply? If so there may be more implications for the developer than they envisaged
(If I work out max demand by the book it will easily be in excess of 100A..)? Each flat is fed via 80A switch fuse in cellar (the only bit of existing installation). If I work it out by the 100% of largest demand & 40% of the rest it's only 84.4A excluding lighting



As far as I can remember,there is no diversity allowable on water heaters.
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