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!
Our ASHP is costing £24 a day to run
Morning,
very new to this and replying from my phone on the A9 driving so not sure how forum works! We installed an ASHP and DWC in feb to replace a dead gas boiler and HWC . We live in an old house that has gone through lots of renovations and are gradually packing insulation in where we can. Electricity costs this week are now at £24 a day which is unsustainable for us! Ground flour is UFH in insulation and concrete, upstairs is rads. We are running the heating at 16 degrees between 6am and 2am and bumping it up to 18 between 2 and 6 when we get 11p electric with our EV tariff with Bulb! Two wood burning stoves in use too! Any advice most welcome! Great site thanks!
Hi @dexters-mum and welcome. So we now know that the forum works whilst driving on the A9. Is this going to be a 'hands free' relationship with the other members?
We would like to know more about the ASHP installation. Did you have an energy survey beforehand? Was the ASHP size & style derived from that survey?
Save energy... recycle electrons!
Lol OH was driving whilst I was searching your forum for answers and Dexter dog snored on back seat! Heat pump is a Warmflow AS03-R32 and a 250l indirect unvented cylinder. Epc before and after installation plus a survey done by energy savings trust.
We have thermostats around the house al set at 16 which is fine but it does mean that the ASHP comes on and off when called for by thermostats, does this use more energy than just having it running all the time? How do you get it to run all the time? 🤔
it does mean that the ASHP comes on and off when called for by thermostats, does this use more energy than just having it running all the time? How do you get it to run all the time? 🤔Posted by: @dexters-mum
In short yes it does use more energy to do that. However, with your EV tariff it might be more complicated to tell you how not doing that would affect what it's costing you.
Other factors of your installation would be useful, but the one that's easiest to change is the flow temperature (how hot the heat pump heats the water). Do you know your flow temperature, if it's running with weather compensation mode, and the flow temperature your system was designed for? You might have a document that says it was designed to run at 45C at -5C for example. Weather compensation mode is described in the manual for your unit on page 51, section 3.11.3
Also you must understand that even with a perfect system, in a cold snap heat pumps run less efficiently and the cost seems tremendouse. Still, there are still things to improve.
Good job it isn't this cold all year round then... Remember, it's only this expensive for the next three months, then it's uphill from there.
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.
There are two threads on this topic live right now and I just want to send a warning based on my own bitter experience. I'll cross-post it in the other thread as well.
I've got a ground source heat pump, and my gshp comes equipped with a 6kW electric auxiliary heater. The auxiliary heater is for emergency operation and frost protection... But it is obviously very expensive because it is basically a whacking great big 6kW immersion heater.
Right after we had our heat pump installed, we noticed our bills were too high... and after a little bit of fact finding, we found out that the installers had set the electric auxiliary heating on and that my system was running in heat pump and 'electric reheating' mode simultaneously. I was cross, but my installer wasn't fussed. My heating bills don't matter to him... all he cares about is that the system 'works'. We sorted it and I forgot about it.
This winter, I noticed my energy usage is a bit higher than I'd like... went back to check and lo and behold, the auxiliary heating is on again. Either the guy who serviced it in the summer messed with it, or the manufacturer changed some settings remotely, or (maybe?) at some point the machine was rebooted and it reverted to some old settings.
Point is: if you are surprised that your heat pump uses too much energy, just ask the question: 'Does my heat pump have electric auxiliary/supplementary/emergency heating'
When your installer tells you 'oh don't worry, it's switched off', don't believe them.
Tell them: 'show me, in person, how to control the auxiliary heating so that I can verify for myself that it is off'. Take some photos of the screen to remind you how it works and save it for next winter.
On my machine, there isn't a simple 'electric reheating on' or 'electric reheating off'. Electric reheating is on, unless you set temperature values that make sure it never comes on. And it's buried way deep in the menus, so you won't find it for yourself.
That’s a good looking heatpump and one of the only ones I’ve seen with a separate call for heat Input for dhw and space heating.
you need to ensure that electric heating is disabled and that weather compensation is enabled.
Whereabouts in the house is the controller for the heat pump?
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.
It’s in a cupboard off the unity room. I really need to learn more about it! The installer was great but didn’t really explain anything about weather compensation!
Posted by: @dexters-mumIt’s in a cupboard off the unity room. I really need to learn more about it! The installer was great but didn’t really explain anything about weather compensation!
sounds like the installer was anything but great then if they didn’t bother to show you how to operate the system efficiently. Any old plumbing monkey can install one of these things, they’re considerably simpler than a Y plan or other standard boiler install, but it takes a certain type to effectively handover the system to the user.
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.
- 26 Forums
- 2,646 Topics
- 61.8 K Posts
- 960 Online
- 7,045 Members
Join Us!
Latest Posts
-
RE: Solar Produced vs Home Consumed
It's worth adding that if you have a hot water tank and...
By JamesPa , 3 minutes ago
-
RE: Heat Pump Overpromising – What Were You Actually Told Before You Bought?
@editor Sorry Mars, I didn’t see a notification about ...
By Toodles , 22 minutes ago
-
RE: Hitachi Heat Pump being replaced with Vaillant
Yes to be configured as a volumiser. The pump is to be...
By trebor12345 , 40 minutes ago
-
RE: Anyone concerned about GivEnergy?
So it seems subscription day has finally arrived for Gi...
By TechnoGeek , 2 hours ago
-
RE: How many people are happy with their ASHP and do you believe them?
I agree, and not. Energy prices are a largely politica...
By JamesPa , 5 hours ago
-
Yes, you will need to notify them even if the inverter ...
By Old_Scientist , 5 hours ago
-
RE: Heat Pump Manufacturers Recommending Buffer Tanks
@tony-stolz, I think @jamespa has already covered the h...
By Mars , 18 hours ago
-
RE: Heat Pump Operation in Summer - Valliant 7kW
I do the same: cool my large buffer (3000L) to 10C, pum...
By upnorthandpersonal , 1 day ago
-
@editor "The interesting bit is that many modern invert...
By Singlespeed , 1 day ago
-
RE: Ecodan & MelCloud scheduling
With the prospect of warmer weather this week, I brough...
By downfield , 1 day ago
-
RE: A2A vs A2W: Which Heat Pump Would You Pick?
I reached out to MCS directly last week on this and her...
By Mars , 1 day ago
-
RE: Help me keep the faith with my air source heat pump installation
My heating developed a really severe case of noise and ...
By JamesPa , 2 days ago
-
RE: Octopus Cosy 12 Heat Pump Regret: Incredibly Loud, Poor Heating & Constant Hum - Help!
@l2jad I was just thinking all things being equal. Our ...
By AndrewJ , 2 days ago
-
Hi, Does anybody have experience with Heat Geek insta...
By sttpd1917 , 3 days ago




