Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!
Temperature schedule for ASHP
Hi all, i am new here.
I have a question about temperature schedules.
We have just had our Octopus survey, waiting for quote for a Daikin system.
We currently do not heat the upstairs, hall set to 18 and rooms in use set to 20 or 21.
During the night we turn all stats down to 13. Using Hive system.
The surveyer said we only get a basic Daikin thermostat an leave it constant day and night.
Surely this is wrong.
If we move to new cosy octopus rates I would plan on boosting through the cheap periond and minimising electricity during day rate and peak rate.
We do have PV and battery but that is smal fry compared to winter heating.
So, do ASHP owners vary temperature to save energy and cost or is it normal to keep it constant?
John
I keep it constant, I don't even have a room thermostat. It runs on weather compensation 24/7. I'm still tweaking the weather comp settings to get things just right.
Cosy is a terrible tarriff.... you'd be much better off on Go.. Heat pumps like to run long and low, boosting the heat for a couple of hours and then coasting through the expensive couple of hours isn't a good strategy in my opinion.
Off grid on the isle of purbeck
2.4kW solar, 15kWh Seplos Mason, Outback power systems 3kW inverter/charger, solid fuel heating with air/air for shoulder months, 10 acres of heathland/woods.
My wife’s house: 1946 3 bed end of terrace in Somerset, ASHP with rads + UFH, triple glazed, retrofit IWI in troublesome rooms, small rear extension.
Your house loses heat 24hrs a day – if you heat the house for only some of those hours then you have to replace the lost heat as well, which if you have a gas boiler just amounts to using the gas at a different time, though there is a modest benefit from a lower rate of heat loss the longer you aren’t heating – so this is what most people expect to do with heating.
Because a heat pump is less efficient if it has to work harder to get the circulating water hotter, the calculations say that more energy is used to reheat up to a temperature after a period of inactivity than to maintain a running temperature.
However, many users do run a setback at night and think it doesn’t alter the efficiency too much, as temps are lower at night which decreases efficiency too. But I think there is a limit to how long you can not heat for before you struggle to bring the house back up to temp – the difficulty is that will vary depending on the weather which makes it hard to schedule.
Lowering the cost of energy is a different calculation to getting the most efficient performance from the pump by lowering the quantity of energy required. It is easier to benefit from time-of-use tariffs with UFH as that can be loaded up – if you only have radiators then you are relying on the thermal efficiency of the house to carry heat between ‘on’ periods.
Mitsubishi EcoDan 8.5 kW ASHP - radiators on a single loop
210l Mitsubishi solar tank
Solar thermal
3.94kW of PV
- 27 Forums
- 2,748 Topics
- 64.7 K Posts
- 2,219 Online
- 7,155 Members
Join Us!
Installer Finder
Degrees of Separation
Latest Posts
-
RE: Volumisers in Heat Pump Systems: Does Placement Matter?
@dave, I think @jamespa has probably identified the mos...
By Mars , 24 minutes ago
-
@kilgorexv, I actually think doing your own calculation...
By Mars , 30 minutes ago
-
RE: Plug and play solar. Thoughts?
My thought is simple. Bring it on and bring on plug in...
By JamesPa , 15 hours ago
-
RE: Heat Geek mini store vs pump size
Yes I agree, that’s why Heat Geek have most likely sele...
By Tomtheheatingengineer , 1 day ago
-
RE: Who's your electricity provider and what's your tariff?
@chandykris Swings and Roundabouts, you win some…. ...
By Toodles , 1 day ago
-
@tomtheheatingengineer, thank you, and welcome to the f...
By Mars , 2 days ago
-
RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
@majordennisbloodnok @tomtheheatingengineer For my ...
By JamesPa , 2 days ago
-
RE: Do I add Air Con or MVHR to existing A2W ASHP?
There is scope for product development here. I for one...
By JamesPa , 2 days ago
-
RE: Is the "divide by 2900" rule still valid?
Really flow rate is a pipework limitation not a water p...
By JamesPa , 2 days ago
-
RE: The good, the bad and the not that great – my heat pump installation
@burtis, I’ve followed this thread pretty much from the...
By Mars , 5 days ago
-
RE: Starting Our Heat Pump Journey: 1962 build 3 bed detached house
First time poster here but I can share my experience as...
By SCH , 5 days ago
-
RE: Is it the house or the equipment?
...which, I've found out, is pretty much impossible to ...
By Majordennisbloodnok , 6 days ago




