Hi, Unfortunately that is very much a "how long is a piece of string" question. The answer depends on so many variables. No two properties will be the same. Some of the dependencies are size, insulation, ventilation, type of emitters (panel radiator or under floor), flow temperature etc. Your best bet is to talk to the people that installed the system.

Bruce

I’d say that was high. How many radiators do you have ? Do you have underfloor heating ? Do you know what flow temperature the hp was running at ? Is the hp set up with weather compensation ? 

17.5 deg C is what I’d consider cold ! Our hp was running in the small hours (min 5 deg outside)  to take the room temp from 21 (overnight setback so hp not running) to 22. The flow temp reached 41 deg C max and by 8am was 37. 

Was it heating your hot water overnight ? What temperature is that set to ?

Many questions ! 
 

My hp is on OpenEnergyMonitor.com so I can see exactly what it’s been doing. It’s a Daikin and there’s very little information available on the app, the controls are very inconveniently in my loft. As well as bringing the room temp up from about 4:30am my hp heated the hot water to 50 deg at 3am. The app tells me I’ve used 7kWh but that’s usually an overestimate as it seems each hour is rounded up to the nearest 1kWh.

Thanks  ​@juliamc 

I have 12 radiators, no underfloor heating.  I didn’t have the hot water on (this is set to 45 degrees.

Yep i do have weather comp active.  I wasn’t in the house for a day/night which is why I had it set to 17.8 - this is typically what my overnight/setback temp is.

I think my flow temp is 39 degrees

AliSim,

Assuming a COP of 4, 10kw would be 40kw of heat output over 10 hours. It does not sound unreasonable for a house large enough to have 12 radiators. The main question is how well insulated is your house? The other question is what was the temperature in the house when the 10 hour period started. If it was bellow 17.8 them the system would be working to get the temperature up. If it was at say 20c before the 10 hour period then, I think, either you have poor insulation or an in efficient heating system

H

Bruce

What temperature is the house getting to now you’re back ? When I first had my hp I turned it to ‘holiday’ mode when we went away for a few days (a cold November). Thankfully I could see the room temperature on the Daikin app, and it had fallen to 13 degrees !! I turned holiday mode off remotely but it took about 3 days to return to a comfortable 21. Since then I’ve never turned it off, though of course it only runs when the temperature outside falls.

Thanks ​@brichard - the house was at 17.5 at the beginning of this period, so working a little to get to 17.8 but 0.3 degrees doesn’t sound massive to me - I’m still an ASHP newbie so am still getting to grips with it!  Re insulation - I guess almost all houses in the Uk can be better insulated but this house is reasonably good.

​@juliamc the house is getting to temp pretty speedily so perhaps it was just an anomaly and perhaps I need to get to grips with having an ASHP is going to be a much bigger drain on electricity than I was expecting

Thanks both for coming back to me on this

It really shouldn’t be a drain on electricity ! Does the unit give you details of the COP (Coefficient of Performance) ? 

I can’t see that it does no.

Hey ​@AliSmi,

Welcome to the community 

It’s lovely to see a couple of our members have already stopped by to offer some help. If you have the time could you upload a couple of photos of your setup? That may help identify anything that’s missing in the conversation. 

You’re in great hands with ​@juliamc and ​@brichard