Electric combi Boilers? Are we nearly yet?

Our Central Heating Engineer has recommended an electric combi boiler (will run it all plus central heating on normal radiators) instead of gas for our small, well insulated 2 bed flat. I’ve checked the forums and can only see older experiences. Any real world ones? Apart from “it’ll be expensive” and “its no good for a bigger house”

I might be wrong here, but why use electricity to heat water to heat the air – isn’t heating the air directly more efficient?

No idea, but could you not just put electric rads in each room? It’d be more efficient as everything could run off individual thermostats/controllers rather than a central controller and TRV’s? Could even go with storage heaters?

Have you got an electric shower? If you have then might want to check that your electricity supply can handle it.

For even better efficiency you could install mutli-split air-con with a single external unit feeding an internal unit in each room, and you’d get cooling in summer in addition to much more efficient heating than a combi or electric radiator. Keep the combi for hot water, just don’t connect it to any central heating (or just turn off the central heating part).

Air con / heat pump is going to be approx 3x cheaper to run than an electric boiler – but cost more to install.

Thanks all. The flat is small, and well insulated. I don’t have space for an ASHPump so may go for a standard electric boiler. Thanks though.

I don’t have space for an ASHPump

No external walls at all?

I don’t have gas in my flat so going to fit those heat retaining electric rads, it will get me from c to b on the EpC but cost 700 each.

What brand are they quoting for? Lots of different tech doing the rounds it seems. The Tepeo boiler caught my eye.

Here you go: https://nottenergy.com/resources/energy-cost-comparison/ – the column to compare is pence per kwh after boiler efficiency

The bottom line is that direct electric heating is *very* expensive.

You’re basically asking us, with no further context, if you should pay to install a system that will cost 39p/kw/h rather than 13p/kw/h to heat your flat. If there’s context missing which makes this sensible, maybe. Otherwise, no.

You indicate you’ve decided to go for it. Honestly, that’s quite likely a very costly mistake.

(@poolman: the maths is essentially the same if you “retain” the heat or use it straight away fwiw)

I would also strongly advise against an electric combi boiler, it’s basically the most expensive to run system you can adopt.

Thanks all- thats really helpful. Do we get a sense that the long term direction of electricity costs as the Wind generated stuff ramps up will bring the unit costs down? Or is that nonsense? I’m weighing the Airsource Heat Pump installation (expensive install) vs a Combi Boiler (cheaper install but much higher running costs at current rates costs) on a small flat we might only be in for 3 years.

Don’t forget to factor in the fact that all electric combi boiler heating might reduce the price you get when you sell by more than the difference in install costs. I would not buy a house with non heat pump electric heating. Of course the house will sell but of the two options gas central heating is more attractive to most buyers IMO.

As for heat pumps? No idea what market sentiment will be in a few years time. I would prefer gas. So a heat pump may get you similar or higher costs to gas, bigger cost to install, and no higher sale price.

If you’re only.going to be there three year then I would just go with whatever works out cheapest. You’re asking on long-term electricity costs but at the same time are probably not going to be there then anyway. When we’re looking at energy strategies for large housing developments we generally advise against direct electric heating due to the costs to run

Don’t forget the resale. Flat with cheaper running costs is going to be more attractive than an expensive to run property so the fact you might only stay 3 years is less of an impact than you think.

Any real world ones? Apart from “it’ll be expensive” and “its no good for a bigger house”

Unfortunately both of those were my experience (it was a 2 bed flat albeit a big one) and the price of electricity has only gone one way in the intervening 13 years. Compare and contrast the availability of renewable energy, does not make for optimism regarding price drops.

Only difference in my case is it was an electric system boiler rather than combi but functionally identical really and we were on Economy 10 for preferential pricing.

Electric boiler. £50 a day.

https://www.dailyrecord.co.uk/news/scottish-news/falkirk-mums-50-day-electricity-26859509

Have a search for eca electric combi on YouTube there’s some good videos on them.