Most efficient way to run ashp

[Jvh2012]

Hi I’m hoping for some advice please; we’ve had a smart meter fitted and I’m convinced there are issues and have been contacting our provider for months. Whilst On holiday the house was using between 10kwh and 15kwh per day with only the fridge freezer and cctv on. Other than ashp nothing else would have been using electricity in that time. 
I’m now concerned with cost of electricity and possibly

a dodgy meter, I need to be running this ashp at its most efficient through the winter months as we are already using an astronomical amount of electricity.

we have an 8.5 kw eco fan ultra quiet ashp with a cop of 4.09 and a 250l hot water cylinder. 
 

Any advice gratefully received!

 

thanks 

[ProDave]

Why did you leave the ASHP on while you were away?

 

I assume you mean Eco Dan (not fan)  there is a thread about these where some models seem to be using a lot of energy when on standby to keep a sump heater operating, figures of up to 200W have been mentioned which would be a little over 4kWh per day for effectively doing nothing other than heating outside.

 

My house during a recent holday was using 8kWh per day.  About 3kWh of that is the treatment plant and MVHR unit, the other 5kWh would have been Fridge / freezer and other stuff left on standby though things that were easy to turn off were.

[Jvh2012]

Sorry yes ecodan. And it wasn’t left on as such I just assumed it would constantly use electric.how would I find out about whether it was keeping the sump heater operating?

 

we have ufh downstairs and radiators upstairs and have no idea how we should be setting these to be the most efficient. I’ve contacted the company who installed but they only installed the ashp now under. Floor heating 

[SteamyTea]

Can you download the half hourly data for when you were away. That may shed some light in that is happening.

[Jvh2012]

How would I do that sorry? 

[SteamyTea]

12 minutes ago, Jvh2012 said:

How would I do that sorry? 

No idea. Do you have a smart meter?

[JohnMo]

How are you currently operating?

 

What are your flow temps, how many zones do you have (TRVs and thermostats) , what temp do you heat your DHW to?

[joth]

2 hours ago, SteamyTea said:

No idea. Do you have a smart meter?

2 hours ago, Jvh2012 said:

How would I do that sorry? 

 

Register for an account with the Bright app

Then connect to their API to download data 

https://brunty.me/post/hildebrand-glow-home-assistant-mqtt/

 

I've not actually tried this yet, but others have.

Edited October 27, 2022 by joth

[Ralph]

3 hours ago, Jvh2012 said:

Hi I’m hoping for some advice please; we’ve had a smart meter fitted and I’m convinced there are issues and have been contacting our provider for months. Whilst On holiday the house was using between 10kwh and 15kwh per day with only the fridge freezer and cctv on. Other than ashp nothing else would have been using electricity in that time. 

Something not quite right there. I'm working from home full time, everything is electric, including waste treatment plant and we have the ASHP heating the main zone room temp to 22/23°C  We are using on average 13kWh.

Edited October 27, 2022 by Ralph

[HughF]

Most efficient way:

 

Throw the timeclock and room stats in the bin, install Homely, set your room temperature...

[PhilT]

1 hour ago, Ralph said:

Something not quite right there. I'm working from home full time, everything is electric, including waste treatment plant and we have the ASHP heating the main zone room temp to 22/23°C  We are using on average 13kWh.

22/23°C ! It's interesting how peoples comfort criteria vary. We're comfortably warm at 19-20 during the day and 20-21 during the evenings. Our average electricity usage during October has been around 10kWh per day total, for a 5 bedroom detached 30 year old self build, with the heat pump using around 5kWh per day, although here in Buckinghamshire it has been a mild October so far. Heat Pump = 11.2kW

[Dave Jones]

according to the 'experts' zoned heating is bad. it should be left on 24x7 with a 3-4degreeC fallback overnight.

[SteamyTea]

5 minutes ago, PhilT said:

It's interesting how peoples comfort criteria vary.

Part of the reason I live in Cornwall now.  Winters are much warmer than Aylesbury.

Do you remember how cold Friars was before the redevelopment.

 

When Bowie, Fish and John Cooper Clarke frequented

 

And now, with a roof.

 

[SteamyTea]

4 minutes ago, Dave Jones said:

according to the 'experts' zoned heating is bad. it should be left on 24x7 with a 3-4degreeC fallback overnight.

Not too brilliant for any heating system except direct electrical resistance heating (fan heater).

[PhilT]

3 minutes ago, SteamyTea said:

Part of the reason I live in Cornwall now.  Winters are much warmer than Aylesbury.

Do you remember how cold Friars was before the redevelopment.

 

When Bowie, Fish and John Cooper Clarke frequented

 

 

And now, with a roof.

 

 

and filming of "A Clockwork Orange". Sigh - the gold ol' days

[Ralph]

6 minutes ago, PhilT said:

22/23°C ! It's interesting how peoples comfort criteria vary. We're comfortably warm at 19-20 during the day and 20-21 during the evenings. Our average electricity usage during October has been around 10kWh per day total, for a 5 bedroom detached 30 year old self build, with the heat pump using around 5kWh per day, although here in Buckinghamshire it has been a mild October so far. Heat Pump = 11.2kW

It's a good point. I had been assuming that 20/21 would be more than enough but where we sit in the evening is beside a lot of glazing and it feels cooler. I also think the open and double height aspects adds to that. Last week heating was 3.1kWh per day and hot water was 2.5kWh per day. We're also not far from the Cairngorms so it's a bit colder.

[SteamyTea]

1 minute ago, PhilT said:

and filming of "A Clockwork Orange". Sigh - the gold ol' days

I think that bit is still there, been a while since I have taken a train into Aylesbury (about 1998)

 

[Ralph]

15 minutes ago, Dave Jones said:

according to the 'experts' zoned heating is bad. it should be left on 24x7 with a 3-4degreeC fallback overnight.

I have noticed that anything more that a 3°C fall back makes for a more expensive day when the system is trying to get back up there.

[PhilT]

8 minutes ago, SteamyTea said:

I think that bit is still there, been a while since I have taken a train into Aylesbury (about 1998)

 

Yes, now divided up between a cycle lane 60% and pedestrians 40% but I only ever saw one cycle since the line was painted about 10-15 years ago - ???

[PhilT]

28 minutes ago, Ralph said:

It's a good point. I had been assuming that 20/21 would be more than enough but where we sit in the evening is beside a lot of glazing and it feels cooler. I also think the open and double height aspects adds to that. Last week heating was 3.1kWh per day and hot water was 2.5kWh per day. We're also not far from the Cairngorms so it's a bit colder.

impressive for Cairngorms. There are only 2 of us and our daily DHW demand is 0.8kWh but we have it set to the minimum 40degC, which easily gives us two good hot showers and enough for the various other minor washing requirements

Edited October 27, 2022 by PhilT

[Ralph]

8 minutes ago, PhilT said:

Our daily DHW demand is 0.8kWh but we have it set to the minimum 40degC, which easily gives us two good hot showers and enough for the various other minor washing requirements

Interesting. Our DHW is at 45°C. I might try taking it down a bit. I also need to look at it's schedule
12:00 to 5:00 - Economy Mode
5:00 to 8:00 - Comfort Mode
8:00 to 15:00 - Economy Mode

15:00 to 20:00 - Comfort Mode

20:00 to 24:00  - Economy Mode

I'm not entirely sure what the modes really mean.

 

[PhilT]

52 minutes ago, Ralph said:

Interesting. Our DHW is at 45°C. I might try taking it down a bit. I also need to look at it's schedule
12:00 to 5:00 - Economy Mode
5:00 to 8:00 - Comfort Mode
8:00 to 15:00 - Economy Mode

15:00 to 20:00 - Comfort Mode

20:00 to 24:00  - Economy Mode

I'm not entirely sure what the modes really mean.

 

We only run it daily at 3pm (the warmest part of the day, on average), in Eco mode, and it takes between 20 and 30 minutes to reach the 40degC set temp.

[ProDave]

1 hour ago, PhilT said:

We only run it daily at 3pm (the warmest part of the day, on average), in Eco mode, and it takes between 20 and 30 minutes to reach the 40degC set temp.

You must have a predictable family routine?

 

2 good showers will empty our tank, and HW has to be available any time of day because "they" will shower at any time of  day that pleases them which is of course not always the same, so "sorry there is not hot water as it is before 3PM" would not cut the mustard here.

 

I have mine timed to come on at 11AM, on the basis there will be enough hot water from yesterday for one shower, and if someone has that early shower I manually turn the DHW on earlier.

 

Random showering times are at odds with trying to be efficient and cost effective.

[Radian]

2 hours ago, Ralph said:

12:00 to 5:00 - Economy Mode
5:00 to 8:00 - Comfort Mode
8:00 to 15:00 - Economy Mode

15:00 to 20:00 - Comfort Mode

20:00 to 24:00  - Economy Mode

I'm not entirely sure what the modes really mean.

Standard Chinese logic to save a couple of 8-bit bytes. They store a proper temperature for a program then use a flag byte held by each time slot to modify the programmed setting by a couple of degrees. Frost, economy and comfort are the usual flags.

[Radian]

3 hours ago, PhilT said:

and filming of "A Clockwork Orange". Sigh - the gold ol' days

 

Hadn't seen these photos before. Google matched it with another:

 

 

I think we can se Stanley Kubrick sitting before the droogs in parkas.