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Updated Data on Dimplex Edal 270L ASHP Hot water tank 1 year full data. Scottish Highlands

Domestic Hot Water & Cylinders

Last Post by Bob@Lochinver 9 months ago

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Bob@Lochinver

(@boblochinver)

Reputable Member Member

Joined: 5 years ago

Posts: 109

Topic starter 23/09/2025 12:06 pm [#2474]

I replaced my oil burning boiler that did hot water and heating back in 2023 and installed Toshiba Haori Airconditioning units for all my heating and cooling, For my complete domestic Hot water supply I purchased a Dimplex Edal 270l all in one ASHP hot water tank. I don't have Gas up here in the sunny Scottish Highlands so while gas is cheaper per kWh of heating required its not an option for me. The House is a 5 bedroom house with 2 Adults and 2 Teenage Daughters. Shower is used at least 4 times a day and standard other house hot water demand. The size of the hot water tank was chosen because the house is large and I felt it best to meet demand. All electric for the hot water is done at cheap rate periods which uses around 450kWh I can also boost the ASHP with the Electric element which brings up total usage to heat water quickly to around 1500kWh. I have an Emporia Electricity monitoring system on all my Electrical use so the figures are as accurate as I can get them. Obviously for a smaller tank all costs would reduce

For a complete year up to Sept 22nd I have used 1420kWh but with my hot water only being heated at the Octopus Cosy tariff cheap rates on average I'm paying around 15p per kWh of electric so that equals £213 for all my hot water usage over a full 365 day year. My previous Oil usage (for hot water was around £450 - £535) but with oil going down considerable its around £266 at present but is subject to wild ups and downs in price.

Hot water demand for a typical family of 4 has a hot water energy demand of roughly 4700 kWh per year so for the various methods of heating the water the costs for the year is as follows:

My Edal 270l ASHP hot water tank £213

Gas Boiler £313

Oil Fired Boiler £266

Direct All electric Immersion £705 This would be charging it only during the cheap rate time of average 15p kWh

It looks like my Edal has worked out cheaper than the rest and I've never had the hot water run out, there is a app that allows me to set various times for heating, temperature, Boost, anti Legionella, it shows me how many showers and baths i have available at any given point and how much overall hot water there is but I've had it say theres zero hot water at the temp ive set it at and still been able to take a shower as it only has to be at 1c below to say theres zero at the temp set so I usually have it set for 52 but in winter set it to 54 to offset the cold.

any questions please feel free to ask.

👍

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ASHP Hotwater Savings

Majordennisbloodnok

(@majordennisbloodnok)

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Joined: 4 years ago

Posts: 1893

23/09/2025 5:23 pm

Thanks for this post, @boblochinver. As it happens, I have a friend who is in the very early stages of investigating moving from a combi boiler to all electric but doesn't have the room outside for a heat pump. However, he could possibly find a home for an air to air unit and your experience of a heat pump hot water tank could just possibly be the last bit of the jigsaw. All good info, so much appreciated.

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Bob@Lochinver

(@boblochinver)

Reputable Member Member

Joined: 5 years ago

Posts: 109

Topic starter 23/09/2025 5:48 pm

@majordennisbloodnok good that the information will be used, I would say that due to the Hotwater tank containing a small ASHP on the top section of it then you need to ensure you can provide two air pipes to the outside (not to an attic). I have mine in my attached Garage to the house and while it it fairly quite I would try to place it where there arent bedrooms due to the sound of the ASHP working at night. Its not excessive but having it installed upstairs in the existing airing cupboard would potentially be heard in the bedrooms. just do a search for Dimplex Edal ASHP and see what it recommends Being on the Cosy tariff helps with keeping the costs down when heating during cheap rates

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Bob@Lochinver

(@boblochinver)

Reputable Member Member

Joined: 5 years ago

Posts: 109

Topic starter 23/09/2025 5:51 pm

Posted by: @majordennisbloodnok

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find a home for an air to air unit

Air to Air conditioning units still need an external Fan much like the fans for standard ASHP's. you can get them that you mount on a external wall as long as theres enough of a gap for them to get good air circulation.

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