First of all, congratulations on your new home and welcome to the forums. I’m sorry to hear you’re having such a stressful experience, especially with a little one to keep warm.

Can you please, if you have it, share your property heat loss with us as well as the size of the ASHP (in kWs). 100 kWh/day is a lot, even with the colder weather we’ve had of late. How big is the property in sqm, roughly? 

Your COP of around 2 suggests the system isn’t running as efficiently as it should, and there’s any number of things that could be contributing to this, and we’ll try to help. 

That sounds really bad, our one uses a quarter of the energy when it is close to freezing. 

Do you have any documentation about the system?  If you do would you be able to type out what people request, information about the system and any settings?

Also is the heat pump heating a hot water tank?  The reason I ask is that for instance our one uses a lot of electricity for an hour in the morning to heat the water to 50C and sometimes if there is anything wrong with it, you end up using more electricity to keep heating the tank all day just because someone didn't set it up correctly.

Finally, we do sometimes find that photographs of an installation can help in diagnosis, would you be able to put some up later?  Something showing the pipes indoors to any tanks, any distribution manifolds that send the hot water out to the floors and radiators, the pumps that circulate the water, and of course the radiators themselves, I assume they have some kind of temperature control valve on them?

Thank you for your reply.!

The property is 150m2.

Unfortunately, i have no idea about heat loss ( did not have a surveryor calculate it.....would it be anywhere on a document?

) ... It is a new build everything is double glazed , and i checked loft and it has thick insulation. there are mild draft here and there, but nothing to cause the upstairs not to heat up if radiators would turn hot. I know for sure that the pipes in garage and around the heat pump need lagging. will attach a picture of loft and model of pump (I do not know the size of it as it is not written anywhere or it might be written but I would not know) ....from 3 pm today until now at 10 pm i consumed 54kwh and had nothing on but my phone to charge . heating upstairs was on since 3 and it is still 19.5 , radiators ice cold. so just put stats to 19.5 to not consume more.

the temp of the flow pipe at the heat pump is 29 degrees....and the return one was 27. i don t know if that helps or what its suppose to be .....

The pump was comissioned in 2021 and there is no documentation if it was ever serviced ...

I hope some of the images atached as it is first ti

me i use this .

i feel i read so much about heat pumps in last 48 h that i am ready to enrol in a full training .....

@anca1808 deep breaths. It’s quite a steep learning curve, but you’ll get there. It just takes time unfortunately to get your head around things. What was your approximate outdoor temperature today?

You have a 8.5kW unit so hitting 100kWh per day is very, very high.

Thanks for the photos that is useful.  A 2 degree drop between out and inflow, that's I think fairly normal, but where is the heat going?  You will lose some through the unlagged pipes by the tank, but then the garage will also feel warm. 

If is is nearly 4 years old and has not been serviced, I can guess there might be some issues, from blockages to wrong pump settings, but assuming the electricity measurement is correct then it should be putting heat somewhere. We can track it down, others will be on here at some point with more experience.

I see the checklist mentions Polypipe Smart Stat, which is apparently one of these:

https://www.plumb2u.com/polypipe-smart-programmable-room-thermostat-ufhsmartw-c2x32033111

do you have it somewhere?

thank you all for the responses and the patience.

Luckly i am on maternity  leave and have a bit of time . although after working 70h/week as a neurosurgeon i did not fancy learning about heat curves 😂

the weather outside today was 14 degrees ....the garage is well insulated , but it is not very warm inside i would say warmer than outside anyway. 

I have those stats all around the house. 4 downstaies and 1 upstairs.

we are wondering the same, where is all this heat going. the meter readingz are accurate i have a smart2 meter . I switched yesterday to an octapus cosy apparently better for heat pumps......noynsure if better with mine as it seems a money pit.

 Should i ask my developer to pay my astronomical bill?

Well if you brought it brand new just now then you surely have a case to go back to them and threaten legal action, but 3 and a bit years latejudging by the commissioning date, you might need to set your solicitor on whoever sold you the house.  Here in Scotland anyway you can get money back from them if things in the house aren't quite right and you let them know within a specific time of moving in.  I suspect a malfunctioning heating system would count, but I am not a lawyer and you should consult one.

Hi Anca1808, 

Welcome to the forum. 

First off, please try not to panic. We just need to do some problem solving. 

1. Where are you getting the kWh reading from, is this from the heat pump control centre, your smart meter?We need to know if that is the reading from the whole house or just the heat pump or just the plantroom area. 

2. Please check your immersion switch is not on. This is the light switch style near the cylinder that is hopefully labelled as immersion, which may have been set up as an on/off override. This will massively increase your total house electricity consumption if left on. Hot water should be heated only by the heat pump and the switch is only for if there's an issue with the heat pump. 

2. That whole plantroom need lagging. I am astounded it has been left like that. This needs to be rectified as a matter or urgency. You can ask the builder if the property was bought from new or if not you can either get some foam builders lagging and pop that on for now until you can get a professional out to do it or just get a plumber out to sort this. 

3. The low differential across the flow and return suggests to me that the heat pump is running against a low volume when the heating is off at the thermostat. Please confirm if you have actuators (white heads on the underfloor manifold) or TRVs on the radiators. The heat pump does not appear to have a volumiser to run against. Heat pumps should run for long periods and then stay off for long periods since steady operation is when they're at their most efficient. 

4. Please upload a picture of the pipework behind the heat pump outside so we can see if this is insulated. 

5. Is the plantroom in an unheated space eg garage or utility? If so this will only further negatively impact the efficiency on the unlagged system. 

6. The commissioning (setup) temps look fine to me and I would not advise that you adjust any settings for now. 

Best, 

Rob at Cirrus Energy

Also from what I have read it isn't impossible for a meter to be wrong but in your case for it to be wrong and the house not heating up is all too much at once. 

Random thought, is there really insulation below the underfloor heating coils?  You can't really tell though without investigation.

To make it a bit clearer as we asked the same about the 2021 commisioning. the house is on a small estate and it is a corner plot build for the developer himself. he wanted to keep the house for him or his family.It has high specs and it is well build . fully brick copper pipes etc , but it was never finished until last year. long story short he did not want it in the end ( got another one bigger)  and it was put on market for sale last year.

Hence the shocking no insulation around pipes.As house was just left....until all the estate was sold and he decided to sell it as well.

I do not know if the unfloor has insulation aroind the coils . all the radiatoes upstairs have trv and there are actuators.

there is no immersion switch....we looked for one and nothing of some sort . unless we did not see it.

i left the settings as they are.

I am taling about the smart meter fornthe whole house. In the house we only have the oven dishwasher and kettel.  when we got the key friday 14 the meter reading was 19450. we moved in with a couch and the cot and aome bits and bobs on 16th night. on 17 i rang octapus to set up my account transfer and they asked for a neter reading again and it was 19680 . they said it is too high to double check and send it again in 24 to 48h. on 19 at 7 am i sent another meter reading and it was 19860 . They said something is very wrong with consuming 400kwh so fast hence why all the drama .Bare in mind i only used kettle 4 5 times,  once the dishwasher and once the oven and yes some lights at night....so i assumed that majority of  it is from the heatpump...