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Does your heat pump calculate and provide you with a COP figure or do you need additional metering equipment to work out your COP? Poll is created on Nov 27, 2022

  
  

Does your heat pump calculate and provide you with a COP figure?

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 robl
(@robl)
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We have had one radiator plumbed in an odd way in parallel to the heatsource, some 10 years ago.  We had a "regular" boiler at the time, with a pump far away from the boiler.  I queried it with the plumber years ago when he did it - he just said I didn't know what I was talking about, plumbed it how he liked, and I just left him to it - it seemed to work with the boiler - but who knew how well as nobody checked beyond everything "gets hot".  Anyway, now we have a heatpump with a cop display - if I turn that radiator on then the COP plummets from 4 down to 3.  It's because that radiator steals some of the flow from the heatpump, so the heatpump has a low flowrate and is forced to supply water inefficiently at a higher temperature (it is a simple heatpump).

In contrast all our other radiators are best left on full - the TRVs are removed from all downstairs radiators, leaving some adjustability in bedrooms.


   
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Morgan
(@morgan)
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@kev-m I can access the energy delivered and consumed but was hoping the MELcloud app would show me the COP like it does on your example.  I don't have MMSP.

Interestingly my heating was turned off during the summer and the ASHP was only heating the DHW yet the MELcloud is still, as per my pic above, still shows energy being consumed for heating.  What's that all about I wonder?

Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.


   
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(@batalto)
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Here is a clear example for people on logging issues with apps. On the left you have the reported from my Midea app, 2kw per hour for the heat pump. On the right is the direct reading through my battery inverter, which tracks house load. Given my base load is around 400w the heat pump is drawing around 1.3/1.4kw - but reporting 2kw. Looks like Midea rounds up, so all my COP figures will actually be better than I calculated. I am going to ask Midea if they can update the app module to include decimal places.

Screenshot 2022 11 29 09 48 30 32 ffcbf0a849eb2d1a437fc62150eff770
Screenshot 2022 11 29 09 48 59 27 55ef112fdffe44c65de534f40acb2de5

 

12kW Midea ASHP - 8.4kw solar - 29kWh batteries
262m2 house in Hampshire
Current weather compensation: 47@-2 and 31@17
My current performance can be found - HERE
Heat pump calculator spreadsheet - HERE


   
Derek M reacted
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(@batalto)
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Update from Midea

Q to Midea:

I was wondering if you were able to update the module for your heat pumps in the app? The reporting only shows in single digits and not decimal places. If you see below its reporting the heat pump consumption as 2kw, when in fact it was less than this. The second image shows my actual power use in the house. From your data you are making your heat pump look much less efficient than it actually is.
 
Is there any way to enable decimal places? It would show much more accurate figures.
 
Answer from Midea: 

Thanks for your reply.

Please note that our technical team is already working on it, and we promise that it will be fixed as Soon as Possible. 

Appreciate your patience.

 

Best regards,
Mark D

MSmartHome Support Team

12kW Midea ASHP - 8.4kw solar - 29kWh batteries
262m2 house in Hampshire
Current weather compensation: 47@-2 and 31@17
My current performance can be found - HERE
Heat pump calculator spreadsheet - HERE


   
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(@scrchngwsl)
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1387 kWhs
Joined: 2 years ago
Posts: 87
 

Posted by: @morgan

@kev-m I can access the energy delivered and consumed but was hoping the MELcloud app would show me the COP like it does on your example.  I don't have MMSP.

Like you, I don't have MMSP and I don't have a "CoP" line on my MELcloud. However, if you use the developer tools on your browser to see the raw JSON response of the report, it does actually contain that information, even though it doesn't show it on the graph.

This is what that looks like (in Firefox):

image

(hope that picture attaches properly)

I've made a script in R to download all the raw data returned in JSON format and plot it, but if you want to do that it's a bit technical. There's no easy way of doing it, and no public API, which is very frustrating...

Interestingly my heating was turned off during the summer and the ASHP was only heating the DHW yet the MELcloud is still, as per my pic above, still shows energy being consumed for heating.  What's that all about I wonder?

My guess is that it's the "idle" power consumption that it attributes to heating (2-ish kWh per day, so 85-ish kW idle). I don't think any of it is measured particularly accurately without the MMSP stuff. Again, frustrating, not sure why that isn't just standard!

 

ASHP: Mitsubishi Ecodan 8.5kW
PV: 5.2kWp
Battery: 8.2kWh


   
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cathodeRay
(@cathoderay)
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Posted by: @scrchngwsl

However, if you use the developer tools on your browser to see the raw JSON response of the report, it does actually contain that information, even though it doesn't show it on the graph.

That is extremely interesting. I was hoping to do something similar with the Midea app, but Midea's app only runs on a smartphone in its own process, not through a browser with access to Developer tools. My intention was to be able to download the data so I can play with it and just as importantly keep historical records. I'm familiar with the basic process as a way of getting the data behind an onscreen chart. I've also dabbled in R (and usually end up tearing my hair out).

Has anyone found a way to access Midea data via a browser?

 

Midea 14kW (for now...) ASHP heating both building and DHW


   
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cathodeRay
(@cathoderay)
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Posted by: @batalto

Please note that our technical team is already working on it, and we promise that it will be fixed as Soon as Possible. 

AKA 'don't call us, we'll call you', 'the cheque's in the post' etc. 

See also above posts on getting to Midea data via a browser - if we can do that, we will have a way of downloading data, instead of having to manually transcribe it. There may even be hidden gems that don't get plotted, as in the above example! 

Midea 14kW (for now...) ASHP heating both building and DHW


   
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Morgan
(@morgan)
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Posts: 540
 

Posted by: @scrchngwsl

Posted by: @morgan

@kev-m I can access the energy delivered and consumed but was hoping the MELcloud app would show me the COP like it does on your example.  I don't have MMSP.

Like you, I don't have MMSP and I don't have a "CoP" line on my MELcloud. However, if you use the developer tools on your browser to see the raw JSON response of the report, it does actually contain that information, even though it doesn't show it on the graph.

This is what that looks like (in Firefox):

-- Attachment is not available --

(hope that picture attaches properly)

I've made a script in R to download all the raw data returned in JSON format and plot it, but if you want to do that it's a bit technical. There's no easy way of doing it, and no public API, which is very frustrating...

Interestingly my heating was turned off during the summer and the ASHP was only heating the DHW yet the MELcloud is still, as per my pic above, still shows energy being consumed for heating.  What's that all about I wonder?

My guess is that it's the "idle" power consumption that it attributes to heating (2-ish kWh per day, so 85-ish kW idle). I don't think any of it is measured particularly accurately without the MMSP stuff. Again, frustrating, not sure why that isn't just standard!

 

What on earth are you talking about? Is this Greek? 😂

JSON, API, developer tools…………….. fair to say you lost me early on in your response 😂😂😂

 

 

Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.


   
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cathodeRay
(@cathoderay)
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6903 kWhs
Joined: 2 years ago
Posts: 1391
 

Posted by: @morgan

What on earth are you talking about? Is this Greek?

It might as well be Greek is you are not used to this stuff. JSON is just a way of storing data, a bit like a CSV file if you are familiar with them, but JSON is much more common on the web. API is Application Programming Interface, basically a gateway that allows others to query data from a server. In plain English, it is a web way of calling your bank and saying send me all transactions from the last month. Put these two (JSON and an available API) together and with the right code you can download data. 

The problem is the API doesn't exist so we move on to method 2, basically looking behind the scenes to see what is being downloaded in the background. That's where browser Developer Tools come in, they allow us a way of seeing whats going on in the background. What @scrchngwsl's screen grab shows is a json response for various things eg Hot water, Heating and COP. Those strings of numbers are the individual data points. You can select them and then copy and paste them into a spreadsheet, and bingo, you have your own data. 

Comment in passing: the COPs are to a vast number of decimal places. I suppose that is possible if they just do a division, but odd not to round them to say 2 decimal places. 

Midea 14kW (for now...) ASHP heating both building and DHW


   
Derek M and scrchngwsl reacted
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(@batalto)
Famed Member Member
3655 kWhs
Joined: 3 years ago
Posts: 1091
 

@cathoderay could you emulate an Android phone on the PC and capture the data coming in. Maybe via wireshark?

12kW Midea ASHP - 8.4kw solar - 29kWh batteries
262m2 house in Hampshire
Current weather compensation: 47@-2 and 31@17
My current performance can be found - HERE
Heat pump calculator spreadsheet - HERE


   
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cathodeRay
(@cathoderay)
Famed Member Moderator
6903 kWhs
Joined: 2 years ago
Posts: 1391
 

Posted by: @batalto

could you emulate an Android phone on the PC and capture the data coming in. Maybe via wireshark?

We talked about this a while back. Emulating android on a PC is a nightmare, and generally fails, mostly on connectivity eg Bluefang doesn't work, stuff in the emulator can't see stuff outside it, so can't set up the app. I had a look at wireshark, and it made my head hurt.

I'm wondering whether mi-cloud ( https://dashboard.mi-cloud.co.uk/login) is the way to go. As I said recently, it appears to have a consumer/home owner dashboard, but I only managed to get into an installer dashboard, and couldn't connect to anything. It's from our dear friends at Freedom, so I am not holding my breath.

Forecast for the next few days especially next weekend looks like it might get cold enough to test our systems a bit more thoroughly. A sort of mini beast from the east coming our way.    

Midea 14kW (for now...) ASHP heating both building and DHW


   
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Morgan
(@morgan)
Noble Member Member
4048 kWhs
Joined: 3 years ago
Posts: 540
 

Posted by: @cathoderay

Posted by: @morgan

What on earth are you talking about? Is this Greek?

It might as well be Greek is you are not used to this stuff. JSON is just a way of storing data, a bit like a CSV file if you are familiar with them, but JSON is much more common on the web. API is Application Programming Interface, basically a gateway that allows others to query data from a server. In plain English, it is a web way of calling your bank and saying send me all transactions from the last month. Put these two (JSON and an available API) together and with the right code you can download data. 

The problem is the API doesn't exist so we move on to method 2, basically looking behind the scenes to see what is being downloaded in the background. That's where browser Developer Tools come in, they allow us a way of seeing whats going on in the background. What @scrchngwsl's screen grab shows is a json response for various things eg Hot water, Heating and COP. Those strings of numbers are the individual data points. You can select them and then copy and paste them into a spreadsheet, and bingo, you have your own data. 

Comment in passing: the COPs are to a vast number of decimal places. I suppose that is possible if they just do a division, but odd not to round them to say 2 decimal places. 

Oh wow. Everything is now so much clearer.......................not 🤨 🤨 🤣 

Probably best I give this topic a miss lol.

 

Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.


   
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