Air Source Heat Pump running it efficiently

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So please talk to me like I know nothing, moved into our house in June last year and the house already had a Mitsubishi Ecodan heat pump and it has been reasonably efficient.
What I want to do is maximise efficiency for this winter with the higher fuel bills.
Some do's and don'ts on how to run it and general advice please

What I want to do is maximise efficiency for this winter with the higher fuel bills.
Some do's and don'ts on how to run it and general advice please

Energy Provider Eon Next v18 2 year fixed ends April 2024 £177.70 per month DD expect this to be sub £150 in the second year of the fix due to our energy usage reduction exercise.
Energy Used Electricity only. Hoping to get down to 6000 kWh a year 4 bedroom detached house EPC high B Designed not retrofitted ASHP Mitsubishi Ecodan, under floor heating ground floor, radiators 1st floor. Multi-fuel burner in lounge.
Dyslexia sufferer don't be too harsh if I get things a bit topsy turdy.
Energy Used Electricity only. Hoping to get down to 6000 kWh a year 4 bedroom detached house EPC high B Designed not retrofitted ASHP Mitsubishi Ecodan, under floor heating ground floor, radiators 1st floor. Multi-fuel burner in lounge.
Dyslexia sufferer don't be too harsh if I get things a bit topsy turdy.
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Energy Used Electricity only. Hoping to get down to 6000 kWh a year 4 bedroom detached house EPC high B Designed not retrofitted ASHP Mitsubishi Ecodan, under floor heating ground floor, radiators 1st floor. Multi-fuel burner in lounge.
Dyslexia sufferer don't be too harsh if I get things a bit topsy turdy.
You could Read this post.
https://forums.moneysavingexpert.com/discussion/6240076/i-bought-a-heat-pump#latest
Do use weather compensation.
Do check that the parameters used for weather compensation are at least roughly correct. If the weather compensation algorithm sets the flow temperature too high you will waste money. If the flow temperature is too low your house will not get warm enough. I'm afraid you have to do this by trial and error, although I found the parameters specified in my MCS certificate were a good starting point.
Don't believe all the myth and mystique surrounding heat pumps. They are not that different from boilers; it's just that getting the weather compensation right will achieve bigger cost savings.
For instance, as we are at home all day ours can idle away at quite a low temp just to balance the heat loss of the house with a night set back of around 3 degrees but it takes hours or even days to reheat if we let the place get stone cold but that's due to the very low flow temps and sluggish response of the underfloor heating.
Our flow temp varies between 30-40 degrees depending on how cold it is outside (-5 then it's about 40, +5 then its about 35 and +10 its around 30, but that suits our bungalow and keeps it at around 19-20 degrees inside)
However there are occasions when its wet and windy but not ever so cold and the weather compensation lowers the flow but cant anticipate the additional heat loss due to evaporative cooling of the house, so the the flow temp might need a bit of a boost so I might tweak it it to +3 or 4 for a few hours to compensate. In the end its down to trial and error but keep notes of what you've done, and what the effect was. Only tweak one thing at a time and give it a day or two to settle between tweaks.
If you've got radiators and want to let the place cool a bit overnight and during the day when you are out at work then you need either larger radiators or higher flow temps and it's high flow temps that reduce the efficiency of the system and often its best just to set it back 2-3 degrees rather than right off.
Likewise keeping your hot water tank temp lower will also save you money - we can get away with 45 degrees and just heat for an hour or two a day and that gives us all the hot water we need (dishes get washed in the dishwasher). We have a low flow shower (6lpm) and we dont spend ages in there.
I would not recommend leaving a heat pump on all the time unless you have underfloor heating. This can be very slow to respond and can take a long time to bring a room back to temperature if allowed to cool. The same applies if you have underfloor heating heated by other means. However, if a heat pump is trying to heat up a room/house quickly it may increase the water output temperature causing it to run less efficiently. Not all heat pumps will do this but if you have one that does it might be more efficient overall to keep it on for longer running at a higher efficiency.
I'm horrified that you house drops by so much in temperature overnight; it must be very badly insulated. My heating is set back by 3 C for six hours at night. Only on the coldest nights does it drop by 3 C and cause the heating to come on early. The low temperature output of a heat pump has little or nothing to do with the time it takes to warm up the house. Underfloor heating is slow because the is a large thermal mass involved. Radiators can be slow if their output is closely matched to the room requirement; oversize the radiator and the room will heat up faster.