I wonder if anyone can offer advice on storage heating circuit design.
I have a job to replace two BS3036 fuse boards, with 17th Edition consumer units. One of the boards will manage the existing storage heaters for the property, currently three heaters, old & no idea of size but each fed via 15amp fuses and 3kw immersion heater. This board receives an 'Economy 7' supply. The property also has 8.5kw electric shower, fed from the standard supply.
My client wishes to increase the storage heaters from three to six. The property has a 100amp supply. Clearly I will need to calculate the new demand, but even just basing it on 2.5kw heaters and the immersion, that is 64amp approx. If the client uses the shower at the same time as the heaters receive their charge, that is approaching 99amps.
I have already advised my client, but if I install 6 x 16amp circuits, there is potential to overload the DNO fuse.
Never installed an off peak board before, I've considered having a DP MCB as a main switch to prevent overload of the DNO fuse, or is it just case of calculating maximum demand for the normal tariff board and limiting the number of off peak circuits?
I have a job to replace two BS3036 fuse boards, with 17th Edition consumer units. One of the boards will manage the existing storage heaters for the property, currently three heaters, old & no idea of size but each fed via 15amp fuses and 3kw immersion heater. This board receives an 'Economy 7' supply. The property also has 8.5kw electric shower, fed from the standard supply.
My client wishes to increase the storage heaters from three to six. The property has a 100amp supply. Clearly I will need to calculate the new demand, but even just basing it on 2.5kw heaters and the immersion, that is 64amp approx. If the client uses the shower at the same time as the heaters receive their charge, that is approaching 99amps.
I have already advised my client, but if I install 6 x 16amp circuits, there is potential to overload the DNO fuse.
Never installed an off peak board before, I've considered having a DP MCB as a main switch to prevent overload of the DNO fuse, or is it just case of calculating maximum demand for the normal tariff board and limiting the number of off peak circuits?
