Instant tankless electric water heater?

[DuckyUC]

Hi everyone

I try to buy/find a Instant tankless electric water heater in uk
as the flat I living in have no gas
and I want instant hot water supply

I contacted coop energy today and they able to do a upgrade of electric service to 100Amp, so now the question is what is the highest kw/amp water heater I could use?

Model	Recommended Breaker	Maximum Amperage @240V	Recommended Household Electric Service	Recommended Minimum Wire Gauge
ECO 27	3 x 40 Amps DP	112.5 Amps	200 Amps	3 x #8 AWG
ECO 24	3 x 40 Amps DP	100.0 Amps	200 Amps	3 x #8 AWG
ECO 21	3 x 40 Amps DP	87.5 Amps	200 Amps	3 x #8 AWG
ECO 18	2 x 40 Amps DP	75.0 Amps	150 Amps	2 x #8 AWG
ECO 11	1 x 60 Amps DP	57.0 Amps	125 Amps	1 x #6 AWG
ECO 8	1 x 40 Amps DP	33.0 Amps	100 Amps	1 x #8 AWG
POU 6	1 x 30 Amps	29.0 Amps	100 Amps	1 x #10 AWG
POU 3.5	1 x 30 Amps	29.0 Amps	100 Amps	1 x #10 AWG

I know the ECO 8 is the open it recommend, but is it possible to fit ECO 21/18/11? as there will be a "save margin" for the Max amp use. I prefer the ECO 18 so even at the peak there still 25Amp left

 

[DuckyUC]

New question, Should I find electrician or plumber to install an instant electric water heater?
I googled it said find part P plumber are the best for this job?

 

[Marvo]

Re: Best 14.4kw+ Single Phase Instant electric water heater exist in UK?

So how many kw needed to support 2 shower at the same time during the winter + kitchen washing machine/dish washer?
14.4kw/60Amp seem a lot but that is talking about the peak usage during the winter time. Most of the time only will be about 1/3-1/2 of the max load. If I get an under power heater 2 showers can't operate at the same that will lose the point of having 2 bathroom really. The water heater only cost about 1-2% value of the flat itself it is really no point to save money by get an under power water heater.

With hot water requirements you can apply a certain amount of diversity same as you can apply to electrical peak loads. Unless you have a massive family or a small guest house I wouldn't size the heater to the maximum possible hot water requirement. I have 5 bathrooms with 3 showers and 2 baths between them and we have a 150litre HWC immersion heater, we don't ever run short of water even though the same sized cylinder would be used in a single bathroomed flat for example. I think you've convinced yourself you need a 14.4kW heater but I think it would be worth getting some professional advice from a plumber before committing to the capital outlay and high installation costs of such a large system.

In answer to your last question you can get anyone who's competent to perform the installation. I personally would get a plumber to install the heater and the pipework and get an electrician to install the supply and isolator etc.

 

[DuckyUC]

Re: Best 14.4kw+ Single Phase Instant electric water heater exist in UK?

With hot water requirements you can apply a certain amount of diversity same as you can apply to electrical peak loads. Unless you have a massive family or a small guest house I wouldn't size the heater to the maximum possible hot water requirement. I have 5 bathrooms with 3 showers and 2 baths between them and we have a 150litre HWC immersion heater, we don't ever run short of water even though the same sized cylinder would be used in a single bathroomed flat for example. I think you've convinced yourself you need a 14.4kW heater but I think it would be worth getting some professional advice from a plumber before committing to the capital outlay and high installation costs of such a large system.

In answer to your last question you can get anyone who's competent to perform the installation. I personally would get a plumber to install the heater and the pipework and get an electrician to install the supply and isolator etc.

Good idea, after I contacted the EHC 14.4kw manufacturer I notice that is not a instant electric water heater, it is design for central heater , now I plan to install the ZIP DEX12 11kw/48A model, I phoned several plumber and one of them did said what you said he need to get a quote from a electrician to know the whole cost of the project.