Electric combi boiler cost to run?

Forum|Forum|3 years ago
January 17, 2023
40 replies
5546 views

Hi all,

Just moved into new rented accommodation with electric heating and water with a combi boiler which seems to be showing about £2.70-£3 an hour estimated cost on the smart meter when heating is on. When boiler is on and ticking over is even showing about £2.30 an hour even when heating is off. Is anyone else on a similar system and know if this is normal as it seems a lot? Sorry have come from being on oil so not used to this type of heating.

Cheers

Chris

Best answer by M.isterW

Electric boilers are notoriously expensive to run. They are a bit more efficient than a gas boiler (100% efficient instead of approx 90%) but electricity is more than 3 times the price of gas per kWh. So whatever someone else pays to heat a similar property with a modern gas boiler, you will pay 3 times as much.

Jeffus

Rank 20

I suspect most of the regular posters here don't have much experience of electric combi boilers rather than gas boilers, including me...

Do you know what make and model of boiler it is as a starter?

Certainly doesn't seem right the electric usage doesn't go down when the electric boiler is off.

I assume there is no gas to the property

C

Chris0291Author

Rank 2

Thanks,

Its a Thermaflow Eleectric Combi boiler.

So I have switched it off now at the mains and it is showing 6p per hour estimated cost but as soon as I turn it on at the mains the cost jumps to 2.30 even with the heating off. Seems way to expensive to me?

M.isterWSolved

Rank 6

Electric boilers are notoriously expensive to run. They are a bit more efficient than a gas boiler (100% efficient instead of approx 90%) but electricity is more than 3 times the price of gas per kWh. So whatever someone else pays to heat a similar property with a modern gas boiler, you will pay 3 times as much.

1992 4 bed detached house. Solar PV + battery, Zappi EV charger, Mitsubishi Ecodan ASHP and i-life2 fan assisted radiators.... No gas 😊

C

Chris0291Author

Rank 2

Yeah I get that but at this rate I’d be looking at about £60 a day which seems extreme?

M.isterW

Rank 6

The high usage when the heating is off seems odd. Do you have a pre-heat setting on the boiler?

Have you tracked your half hourly electricity use over a few days? That would show if you're using a lot of electricity all the time or if there are peaks, when the boiler is working.

1992 4 bed detached house. Solar PV + battery, Zappi EV charger, Mitsubishi Ecodan ASHP and i-life2 fan assisted radiators.... No gas 😊

Jeffus

Rank 20

So having only had a brief look

https://thermaflowheating.co.uk/electric-boilers/

It looks to me like these have a thermal store of hot water for the heating and domestic water that ideally gets heated up primarily at off peak tariff i am assuming and topped up at other times?

Is that your understanding or have i misunderstood?

Is there a big tank somewhere?

If i am correct the tank of water may get heated up when the heating is not on.

It doesn't look like a simple electric boiler that simply heats water when needed or with just a small buffer.

Do you know which of the models you have on the website?