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Hi @f1p
I'm finding the basic analysis available within MelPump really useful, even without having added the dongle as yet.
One query on something that looks a little odd within it though, the Delta T graph line appears differently within the detailed report than it does within the temperature report. On the detailed report it has large sections of zero reporting when the temperature graph shows a different result within it. From what I can see, this looks to be when the system reports as 'Idle' on the detailed chart, and it defaults to showing a Delta of zero at this time, even if the system reporting within the temperature graph shows a non-zero figure.
I'm not sure if this is intentional, but presumably the output on the temperature report is the 'correct' version of the data?
130m2 4 bed detached house in West Yorkshire
10kW Mitsubishi Ecodan R290 Heat Pump - Installed June 2025
6.3kWp PV, 5kW Sunsynk Inverter, 3 x 5.3kWh Sunsynk Batteries
MyEnergi Zappi Charger for 1 EV (Ioniq5) and 1 PHEV (Outlander)
User of Havenwise (Full control Jun-Dec 2025, DHW only from early Dec)
Subscriber to MelPump App data via CN105 Dongle Kit
Posted by: @sand@sheriff-fatman 🤭 ill be interested in your thoughts on Home Assistant Green box
I'm trying to convince myself I need one.
Going to try melpump app first.
I've been in receipt of the Green box for 48 hours now, and having had no prior experience of Home Assistant to this point, these are my initial thoughts.
Set up was very simple, and it works straight out of the box. YouTube videos on the process are plentiful so I had some way to benchmark how to go about this, but it pretty much is a case of plugging it in and typing in the web address advised to get set up with an account.
I was hoping to see a vast amount of automatically recognised tech appear when it did the initial search, but the results were underwhelming, and mainly things that I wasn't planning to immediately connect, such as an Apple TV box. I've noticed that the auto-recognition has continued to add the odd thing since then, so it isn't necessarily a one-time search.
However, from there I have managed to connect most of the energy consumption tech that I'm interested in to Home Assistant. Some of this was via official HA integrations, and others was via the community written stuff, most of which comes via an add-on depository called HACS. To date I've brought in data from the Sunsynk inverter & the myenergi car charger via this route, and I've spotted that there is an integration for Octopus Energy which is the next on the list. I got sidetracked in trying to configure a 'card' to work to display the energy movements in the house, although I think I've started to make progress on this.
I'm now at the stage where the main dashboard is literally a random dumping ground of all sorts of data that has been pulled in, so the immediate task is now to create a dashboard that does the stuff I want to do in a concise way. This is likely to be a voyage of discovery, and I'm sure there will be plenty of bleep filters required along the way, but my immediate instinct is that there's probably something already written out there that I can crib to do the job for me, via getting it to point to the right 'entities' on my system, which seems to be the term for individual bits of data being reported from somewhere.
It's very much a case of learning while trying to play around with things, and I'm already confident enough to realise that the trial and error within new dashboards won't break anything in the template ones. I'm navigating a world where the terminology is all new to me, so GitHub, Lovelace, etc are terms that keep popping up regularly, but I'm finding that I can navigate around them sufficiently without needing to fully understand them. I'll learn gradually by trial and error, and I'm sure I'll start to want to do more with it as go along. As and when I need to, I look for a YouTube video or on-line resource to try to answer the specific challenge I have, and so far this has been reasonably successful.
In less encouraging news, I can see how this has the potential to become an obsessive time-sponge too!
130m2 4 bed detached house in West Yorkshire
10kW Mitsubishi Ecodan R290 Heat Pump - Installed June 2025
6.3kWp PV, 5kW Sunsynk Inverter, 3 x 5.3kWh Sunsynk Batteries
MyEnergi Zappi Charger for 1 EV (Ioniq5) and 1 PHEV (Outlander)
User of Havenwise (Full control Jun-Dec 2025, DHW only from early Dec)
Subscriber to MelPump App data via CN105 Dongle Kit
@sheriff-fatman Do you use the forecast.solar thingy? If so, is it working okay? I ask because mine has been fine for ages, but two days ago it became "unavailable", and all the factors have reset to 0.0kWh. No idea why, as I've not changed anything.
Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.
14 x 500w Monocrystalline solar panels.
2 ESS Smile G3 10.1 batteries.
ESS Smile G3 5kw inverter.
Posted by: @morgan@sheriff-fatman Do you use the forecast.solar thingy? If so, is it working okay? I ask because mine has been fine for ages, but two days ago it became "unavailable", and all the factors have reset to 0.0kWh. No idea why, as I've not changed anything.
I don't plan to use this, as our property is subject to tree shading from trees with TPO's on them, so was always going to be a limiting factor for us when installed in 2022. I had optimisers put on every panel to address this as well as possible (most standard quotations initially proposed none, or only partial coverage) and this in hindsight has been a wise move, as I can monitor each panels output individually, including two occasions where the optimisers have failed and required warranty replacement.
If I used a forecasting tool, I'd simply be comparing to a theoretical number that isn't achievable for us, so it's a largely meaningless number in my case.
130m2 4 bed detached house in West Yorkshire
10kW Mitsubishi Ecodan R290 Heat Pump - Installed June 2025
6.3kWp PV, 5kW Sunsynk Inverter, 3 x 5.3kWh Sunsynk Batteries
MyEnergi Zappi Charger for 1 EV (Ioniq5) and 1 PHEV (Outlander)
User of Havenwise (Full control Jun-Dec 2025, DHW only from early Dec)
Subscriber to MelPump App data via CN105 Dongle Kit
Posted by: @morganDo you use the forecast.solar thingy? If so, is it working okay? I ask because mine has been fine for ages, but two days ago it became "unavailable", and all the factors have reset to 0.0kWh. No idea why, as I've not changed anything.
I think it may be because the Met Office has/is going to completely change its API (was supposed to happen on 1st December, but given what other Met Office forecasts are like...). I got an email about it because I use the Met Office for other stuff, the HA thingies probably just fail. Maybe have a look in the HA logs, more info on the Met Office website about the changes here.
Midea 14kW (for now...) ASHP heating both building and DHW
Posted by: @cathoderayPosted by: @morganDo you use the forecast.solar thingy? If so, is it working okay? I ask because mine has been fine for ages, but two days ago it became "unavailable", and all the factors have reset to 0.0kWh. No idea why, as I've not changed anything.
I think it may be because the Met Office has/is going to completely change its API (was supposed to happen on 1st December, but given what other Met Office forecasts are like...). I got an email about it because I use the Met Office for other stuff, the HA thingies probably just fail. Maybe have a look in the HA logs, more info on the Met Office website about the changes here.
I saw the same thing at the same time. The forecast.solar site was unreachable in its entirety, so I made a mental note to switch to another forecasting API. However, when I looked again yesterday it was back up and running again. Looks like someone's IT dept had a bit of a bad day.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; sumus solum profundum variat"
Posted by: @cathoderayPosted by: @morganDo you use the forecast.solar thingy? If so, is it working okay? I ask because mine has been fine for ages, but two days ago it became "unavailable", and all the factors have reset to 0.0kWh. No idea why, as I've not changed anything.
I think it may be because the Met Office has/is going to completely change its API (was supposed to happen on 1st December, but given what other Met Office forecasts are like...). I got an email about it because I use the Met Office for other stuff, the HA thingies probably just fail. Maybe have a look in the HA logs, more info on the Met Office website about the changes here.
@cathoderay So will it simply fix itself, or is forecast.solar dead and gone now? If that's the end of it, is there an alternative? I often use the forecast to manually charge my batteries if it predicts a poor day.
Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.
14 x 500w Monocrystalline solar panels.
2 ESS Smile G3 10.1 batteries.
ESS Smile G3 5kw inverter.
@morgan — I use historical Met Office observational data for other things, not the forecasts, but I know about the HA Met Office based integration with forecasts because of my time spent trying out HA. I'm guessing that integration uses the Met Office API that is going to disappear on 1st December, and I also guessed they've been messing with it in advance. From the Met Office page I linked to, it looks like there is no direct replacement, but maybe other options and/or use a different forecast API, @majordennisbloodnok may have some suggestions.
Midea 14kW (for now...) ASHP heating both building and DHW
I've created a new thread for the dongle config here ( https://renewableheatinghub.co.uk/forums/postid/53559/) so as not to let the offshoot distract too much.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; sumus solum profundum variat"
Posted by: @cathoderay@morgan — I use historical Met Office observational data for other things, not the forecasts, but I know about the HA Met Office based integration with forecasts because of my time spent trying out HA. I'm guessing that integration uses the Met Office API that is going to disappear on 1st December, and I also guessed they've been messing with it in advance. From the Met Office page I linked to, it looks like there is no direct replacement, but maybe other options and/or use a different forecast API, @majordennisbloodnok may have some suggestions.
Thanks, @cathoderay.
I was aware of some changes to the Met Office API, but at least as of now the HA integration is still working. I think this is probably a red herring, though, since forecast.solar is a separate API run by a separate organisation purely for forecasting likely solar PV production given the number, location and orientation of your panels. As such, whilst it's potentially possible they may use the Met Office to forecast how sunny it will be, their API doesn't require anyone to pull data from elsewhere as a prerequisite.
The hiatus a couple of days ago was certainly something I noticed in HA but when I went directly to forecast.solar's web site independenty of HA the whole site was down. It's back up again now and the HA integration is working again exactly as it was before.
There are at least two other similar organisations that provide much the same service (and HA has integrations for them too), and current wisdom is that forecast.solar is not quite the most accurate of them. However, it's the only one of the three that's an "official" HA integration and so is the easiest to set up. If it stopped working for good, I'd probably move over to using Solcast instead, which also happens to be one of the prerequisites for the all-singing all-dancing fancy addon called Predbat - or batpred - and which is supposed to optimise home battery charging and discharging, but that's another (very big) discussion for some other time.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; sumus solum profundum variat"
Just wanted to acknowledge that @f1p has provided very speedy assistance with a technical issue I had today (the device lost connection to Home Assistant by the looks of things, so all the data updates went offline).
I'm back up and running again, and it was potentially a wifi issue while the house was empty that caused the problem, but I can vouch for the eBay comments and other user experiences I've read regarding the availability of support for the device.
130m2 4 bed detached house in West Yorkshire
10kW Mitsubishi Ecodan R290 Heat Pump - Installed June 2025
6.3kWp PV, 5kW Sunsynk Inverter, 3 x 5.3kWh Sunsynk Batteries
MyEnergi Zappi Charger for 1 EV (Ioniq5) and 1 PHEV (Outlander)
User of Havenwise (Full control Jun-Dec 2025, DHW only from early Dec)
Subscriber to MelPump App data via CN105 Dongle Kit
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