electric boilers

[badwolf]

Hi chaps,

I have been asked by a plumber to quote to wire 2 x 10kw electric boilers, supply is single phase 100A.

He tells me that there has to be 2 and there is no way he can install a gas boiler without mega chasing of floors etc., but at 20kw total load that equates around 87A, i can't apply diversity as they are thermostically controlled.

I thought of a priority switch, but this is no good as he may need both on at the same time.

Am i right in saying he needs another phase or the plumber has to actually work for a living?

 

[Engineer54]

Is this for a domestic installation?? Surely not!!!

 

[badwolf]

yup for a house, he says that he needs 2 cos the output from one wont be enough, ive fitted 4 or 5 before, but never 2 in the same install, i have tried telling him 1 would be fine, but he wont have it!

 

[badwolf]

hes a good plumber, but hes had no experience of electric boilers, and ive never had to size one before as the plumber usually does it, and ive not been to the site yet, i thought as a plumber he should know.

 

[Engineer54]

The Guy's a Nutter!! lol!!!

 

[cr0ft]

I do plumbing and fit these boilers from time to time (plumbing is my main trade). If they are electric storage heaters basically (i.e. the cylinder contains central heating water rather than hot water for the taps) then a 10KW boiler will easily provide enough heat for the requirements of a 3 bedroom home. Any more than that and a company called Thermaflow make good 12KW boilers to do 4 bedroom properties. Above that and you might struggle to find one that will meet your requirements.

 

[badwolf]

i think he wants it to do heating and dhw, i told him he could use a normal cylinder with dual immersions for dhw and one boiler for heating, but he wants whatever device he fits to heat a 3 bed and supply the hot water, do you know of such a product? i dont know the conversion between btu/heating kw and electrical kw, but he says that 34000 btus which according to heatrae sadia is 10kw at 230v, wouldnt be enough.

 

[badwolf]

thermaflow do electric combi's, if that not good enough, nothing will be !

 

[Andyfm]

I wired a twin 10kw system recently but there was already a three phase supply in the building as they used to have a lot of storage heaters - would do it on a single phase supply though.
Get him a quote for an extra phase, that`ll change his mind.

 

[cr0ft]

My company is Thermaflow's approved installer for the Lincolnshire county. They are quality bits of kit but not cheap. 3412 BTU/h = 1KW. Worth gently reminding him that you don't size them like conventional gas boilers as the Thermaflows and other heating/dhw electric boilers work by storing several hundred litres of water attached to the central heating system. This stored thermal energy is used much like a battery or capacitor to provide power to the rads over and above the 12KW of electrical power supplied to the boiler.

End result is a 12KW electric combi-boiler is more like a 30KW gas boiler to be honest.

It does sound like he's not too familiar with how the systems work. I've never come across a domestic property that needs 2 of these boilers installing.

 

[Rampage]

It's not for something silly like a fish pond is it?
Interesting that your in Wimbourne as there is a very large pond being built in Dorset somewhere at the moment!

 

[leonard]

It's not for something silly like a fish pond is it?
Interesting that your in Wimbourne as there is a very large pond being built in Dorset somewhere at the moment!

Hi all

I was looking for some information on electric boilers .

I have to install a new electric boiler next week on a small flat only for hot water and shower ,what kind of boiler do you recommend ?
have been told to use one over 9KW to be sufficient for the shower .The Santon PremierHeat Electric Flow boilers 4kw, 6kw, 9kw, 11kw, 12kw