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Thanks, @hcas.
When I tried to take a look at Melcloud Home, it told me it's only for aircon units. Do you know of anyone yet with a heat pump who's using the new Mitsi app?
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"
I had to de-register my current connection and sign up again (UK) on the web app (play store isn't yet available in the UK)
But there are official migration guides on YouTube for the likes of the Netherlands which you could try the steps from within MELCloud
@majordennisbloodnok The migration hasn't started in the UK, so not really.
We've seen it in other places in Europe. The "new" Melcloud Home app isn't so different from the current Melcloud app based on what I've seen.
CEO and co-founder at HavenWise
I have now managed to tweak a few DIP switches to get all the required data through now and I have to say Im really impressed with the dongle (Mitsubishi Ecodan Heat Pump to MQTT/Home Assistant and MELCloud WiFi or Ethernet) and the data displayed in Melpump. For the price its a real bargain. Here are some screen shots.
It has really diagnosed some of the issues at this facility so that I can go about fixing them.
@editor would you like a write up of this for your articles?
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
5kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
@bontwoody Very interesting indeed. I have started a trial with HavenWise and I think we are moving forward, but I am not entirely convinced at this stage and there are some aspects that I am not so keen on.
Could you clarify something for me please? As I understand it HavenWise collects your data and then uses this to manage the system with algorithms that are more sophisticated than MelCloud can provide through weather compensation, etc.
On the other hand, does MelPump just provide you with rather more detailed information for you to carry out the management more effectively, or do they also do management?
I love the idea of having more information, but I am not at all sure I can devote much more time to acting upon the additional data.
342sq m "Upside down" house in Algarve. Portugal
Mitsubishi PUHZ-120YUK 12kW ASHP
12 Solar Panels Growatt Inverter
2 x Growatt 7.5kW Batteries
Fronius EV Charger
Kia e- Niro 64kW
Thanks @bontwoody!
It's worth noting that you did purchase the Home Assistant version, but converted the firmware to the tailored "MELPump" firmware (which is easier to link with the App and gets automatic OTA updates)
It's straightforward to do; however there is a separate listing so it can ship it pre-installed if others are interested.
@davidalgarve Im only just beginning to scratch the surface David but it seems that there are some energy saving features in Melpump although maybe not as advanced as some of the other options like Havenwise and Homely. I will screenshot them below:
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
5kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
Posted by: @davidalgarveOn the other hand, does MelPump just provide you with rather more detailed information for you to carry out the management more effectively, or do they also do management?
Both,
There are options for Eco & Dynamic Tariffs and Smart Solar modes etc. but probably not to the same level as hands-off as Havenwise
Then also the powerful data to root cause specific issues, look into underlying design and share with your installer/service engineers etc. to make adjustments
I read this thread with some interest a couple of weeks ago, but was initially put off by the prospect of having to open up the heat pump and fiddle about with installing a connector within it.
Having returned to it yesterday and taken a closer look at the MelPump website, I realised that there's a level of access available that doesn't require this, and it will utilise the data available in MelCloud to report information in a more user-friendly format. I was also concerned that, being an existing customer of Havenwise, which I use to control the heat pump, that the two would somehow interfere with each other, as MelPump also offers functionality to fine-tune the performance of the pump through the app.
Having re-assured myself that this wasn't the case, I've now commenced an initial 30 day trial of MelPump, as a user accessing just the MelCloud data within it. First impressions are good, and the availability of information is much more accessible than within MelCloud, as expected. On the basis of what I've seen so far, I suspect that the annual subscription cost will likely be a worthwhile investment for me, even without the additional data available from the dongle. That's a step further that I'll need to consider in due course, with my main initial concern being the ease of connecting it and any potential impact on Mitsubishi's 7 year warranty that doing so might create, should an issue arise with the heat pump itself.
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 Interesting because I am considering something similar. I am still in the trial period with HavenWise and it was a disappointing start with a long period before the performance seemed to approach my previous weather compensation levels. Of course, comfort is one thing and running costs are another. Currently, I am not seeing any improvement in the ability to easily collect data to evaluate performance and it would appear that MelPump would offer much more in this direction, but give less direct control.
I can't see me paying two subscriptions, but I will find it hard to decide between the two.
342sq m "Upside down" house in Algarve. Portugal
Mitsubishi PUHZ-120YUK 12kW ASHP
12 Solar Panels Growatt Inverter
2 x Growatt 7.5kW Batteries
Fronius EV Charger
Kia e- Niro 64kW
Posted by: @davidalgarve@sheriff-fatman Interesting because I am considering something similar. I am still in the trial period with HavenWise and it was a disappointing start with a long period before the performance seemed to approach my previous weather compensation levels. Of course, comfort is one thing and running costs are another. Currently, I am not seeing any improvement in the ability to easily collect data to evaluate performance and it would appear that MelPump would offer much more in this direction, but give less direct control.
I can't see me paying two subscriptions, but I will find it hard to decide between the two.
I signed up to Havenwise control on the day after the heat pump was commissioned so, unlike you, I don't have any prior data to compare to. I'm intrigued by how the algorithms are working on my system, and having access to both datasets will help me to assess this over a heating season. My system was installed in late June, so it's only in recent weeks that I've started to experience it being used for heating, and this week is particularly intriguing as temperatures approach freezing point for the first time.
At present, I'm very happy with how the heat pump is performing, measured in terms of like for like cost savings vs equivalent periods last year, and also the comfort within the house. As I've noted elsewhere, my COP figures are on the lower side of expectations (overall COP of around 3.0 since installation) but this may be a function of how Havenwise chooses to run it, which has been in bouts of harder, short blasts of use with longer idle periods, partly as it was set up to take my Octopus EV tariff into account, a setting which I've only recently amended to trial the alternative option of ignoring it and applying more of a 'low and slow' approach (the limitation of the tariff method is that it has no sight of my solar and battery system, so can only work with the time of use tariffs in its calculations, when in reality the system may be using solar or stored battery power in the peak periods.
The current week is the first time I can recall where the idle time of the system has dipped as low as 30% in a 24 hour period, and it's also the first time where there's been recognisable cycling in the usage profile (NB: these are 'normal' cycling periods of around 3 per hour, rather than any short cycling concerns). It's an R290 pump, so has a wider range of flow temperatures, which again may be a factor in the COP figure. Ultimately, if the reduction in billed costs meets my expectations then that's the measure I'm interested in, rather than achieving a specific SCOP figure.
In terms of the subscription costs, I'm viewing each of them differently as Havenwise is the controlling option (and £60 for a year for that functionality was essentially planned into how I would set up the system from installation). MelPump, which I've only become aware of recently is, for now, intended as a reporting tool for me to get under the skin of the data as much as possible, and £25 for a year of that feels like a decent investment, given that I'm frustrated by the availability of usable data from other sources to the extent that I'd like to have it, which is admittedly more than a typical heat pump user would want to have access to.
Based on the limited time accessing MelPump, the control functionality has more manual interaction available to an end user, and is perhaps more capable of a user 'cherry picking' the bits they want to use to fine tune their systems. By comparison, Havenwise control is much more a case of trusting the algorithms to do the job based on the parameters that you set for it. If you only plan on paying for one subscription in the longer term, then that's probably a good basis for thinking about which method of control you prefer.
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
Hi we moved into a new build ecodan already installed. There was no flow meter or energy data pack supplied with the install, so we have never been able to see cop. Would this show this information ?
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