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Let's not forget that "good enough" is a variable term. For most homeowners, the measurement of CoP or SCoP being a few percent out is largely irrelevant - especially if what it reports is always out by the same percentage - since it's far more important to us inveterate tweakers to see changes in the figure rather than the figure itself. As a result, "good enough" can accept quite a lot of wiggle room. In contrast, a manufacturer publishing a CoP figure with even a fairly small discrepancy could land themselves in a lot of regulatory hot water - even if the CoP figure has been gamed to be as good as possible. As a result, "good enough" for a manufacturer has a much finer tolerance.
My personal view is that if a homeowner is trying to keep an eye on how well their installation is performing and improve performance where opportunities arise, using the inbuilt sensors is fine so long as they maintain a consistent accuracy. If the homeowner wants to challenge the manufacturer's published figures or keep track of performance relative to other systems, it's likely some third party sensors with known and published levels of accuracy are probably necessary.
For me, the little gizmo @f1p is selling is doing nothing more than making available all the data my heat pump has been gathering for itself already. Yes, it also provides some extrapolated estimates of certain figures, but once again it does so with consistent accuracy so comparison over time is still valid. It's good enough for my needs and (importantly) far more fit for purpose than the Melcloud setup.
As for @sheriff-fatman's anecdote about the Aira heat pump owner, I completely agree; that is why I have a strong distrust of any companies (heat pump manufacturers OR, indeed, heat-pump control service providers like Homely) that actively try to keep homeowners away from the raw data the heat pump generates. If a system is performing well, why not let the homeowner independently verify the fact and bask in the reflected glory. The only reason, in my opinion, for keeping heat pump owners away from that basic data is if there's something to hide and my little CN105 dongle thingy now means my heat pump is an open book for me.
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: @majordennisbloodnokLet's not forget that "good enough" is a variable term.
I agree, it is always dependent on context. What is 'good enough' for a young lad or lass landing an elastic band powered balsa wood model plane in his or her back garden may not be good enough for a fighter pilot landing his plane on an aircraft carrier at sea. The term for me comes from the 'good enough' mother, a concept developed by Donald Winnicott which means, well, it means what it says, a mother who is good enough but not perfect, and it carries the assumption you don't need to be perfect. It marks the dividing line between what can be accepted, and when something needs to be done. I think in general it scales well enough to whatever context it is used in.
And I agree, for most people monitoring their heat pump, manufacturer sensor based monitoring is good enough, all the more so as much of the time we are looking for as you say relative changes (COP better or worse, flow temp better or worse) rather than absolute numbers. Does it really matter if the monitoring shows the flow temp went down from 47 degrees to 44 degrees, when in fact it went down from 48 to 45 degrees? I doubt it. What matters is you moved the flow temp in the right direction, by a probably useful amount.
In therapy, the good enough concept is often very useful in treating moderate cases of HPDHD (Heat Pump Deficit Hyperactivity Disorder). Severe cases on the other hand usually need admission to a special unit, where all heating system controls have been been placed behind locked doors. Extreme cases sometimes end up in padded cells, where the padding works by restricting access to any heat emitters in the cell. My advice to anyone who thinks they may be developing HPDHD is to repeat to themselves ten times every 15 minutes 'my heating is good enough'. If that doesn't work, get a referral to a specialist, sooner rather than later.
Midea 14kW (for now...) ASHP heating both building and DHW
Posted by: @majordennisbloodnokPosted by: @morgan@majordennisbloodnok it isn't obvious where on their site one finds where to get a forecast.
That’s not a problem. If you can hit the main landing page (which you obviously seem to have managed) that’s all I need to know. It confirms there’s no problem between your home and the web server.
Having read up more, the API shouldn’t need a key at all. I don’t know if it used to but doesn’t now or what, but I’ll need to get back home to see what I can see from my home network before going any further.
OK, so I've taken a look at my HA instance and it seems the forecast.solar site's free plan does not need an API key and so the problem with your instance isn't what I thought it was.
If you go to Settings, Devices and Services, find the forecast.solar device and click on it you should see something like this
Clicking on the little configuration cog should get you to a screen entitled "Options" where you can tweak the relevant settings (API key if you were using one, direction your roof is pointing, roof elevation, kWp of your panels and so forth). If you leave the settings as they are and just click the Submit button, does that kick it into working?
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...
In therapy, the good enough concept is often very useful in treating moderate cases of HPDHD (Heat Pump Deficit Hyperactivity Disorder). Severe cases on the other hand usually need admission to a special unit, where all heating system controls have been been placed behind locked doors. Extreme cases sometimes end up in padded cells, where the padding works by restricting access to any heat emitters in the cell. My advice to anyone who thinks they may be developing HPDHD is to repeat to themselves ten times every 15 minutes 'my heating is good enough'. If that doesn't work, get a referral to a specialist, sooner rather than later.
In contrast, after a suboptimal installation by cowboys, the homeowner is likely to need to cope with a significant amount of Compromise Reduction And Prevention. The typical first step in this process is a Full Audit of Numbers, and to ensure the best outcome of the Compromise Reduction And Prevention hitting the Full Audit of Numbers, it may be beneficial to lock said homeowner in aforementioned cell along with several sharp objects and the original installer. This may not benefit either the installer or the underperforming system but the homeowner often reports feeling much better.
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"
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: @majordennisbloodnokit may be beneficial to lock said homeowner in aforementioned cell along with several sharp objects and the original installer
Sounds like an excellent operative intervention to me!
Midea 14kW (for now...) ASHP heating both building and DHW
Ah, OK. I think, when you were clicking on the forecast.solar device, you clicked on the "1 service" link rather than the "Forecast.Solar" link. No matter; from the screenshot you've uploaded, can you click on the bit I've highlighted here, please?
That'll get to the same place I showed in this screenshot
...where you can see the little cog icon. That's the one I'd like you to press, and it'll give you a screen looking like this
No doubt your options will be slightly different to mine, but what I'm interested in is what happens when you get to this screen and then just click on the Submit button (i.e. reapplying the same options you had there to start with).
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"
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.
Bingo. Sometimes a judiciously placed size 10 bovver boot does wonders....
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"
A sneak preview of the onboard compensation curve designer that is going to be built into MELPump for use only with the adapter.
Still tweaking the design - e.g. it would be great to add "live" point to show where on the curve you currently are and therefore you can adjust your points to help optimise.
As mentioned previously, the online tool is only a visual designer, the saved settings are sent and kept locally onboard the adapter in your home so it can operate in the case of WiFi drop out or connection loss with the Internet (when we look at the adapter wifi connection data of the ~2700 users, this is important for reliability)
@f1p Looks good, and will likely be something I use when it becomes available (is it sad that I've picked up that there'll be a new colour coding for the operation mode?) My free trial of MelPump has just expired, so I've just started an annual subscription used primarily for the data reporting, so this will be a useful additional benefit, even if I somehow succeed in implementing the steps outlined by @majordennisbloodnok to get direct control via a 'geekier' route, which I'm still psyching myself up to attempt.
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
Very excited to see that the online curve option has now gone live within the Mel Pump app, making the task of setting up a bespoke curve much easier that the 'geeky' option that @majordennisbloodnok had discovered a few weeks ago.
I've dived straight in to try to tweak the settings around the 4-6°C OAT range, where the pump currently can run in equilibrium mode for long periods on the weather curve at 4°C, but has a meltdown when it has to adjust slightly at 5°C and starts cycling. Ultimately, I might end up with an optimum flow temperature setting at each individual OAT, and this gives me the ability to create such a beast.
Baby steps for now, but this is what I've gone with as the first attempt. It's potentially a tinkerer's dream, but hopefully it will help to iron out some of the performance niggles over time.
By a freak of timing, this availability has come within 24 hours of my short-lived trial of Mitsubishi's in-built auto-adapt mode, just to see if it would deliver any improvements via it's so-called ability to learn. I switched it on just before sitting down to eat with the family and went back to check on it about 30 minutes later, during which time it had increased the flow temp at 6°C OAT from the weather curve setting of 35°C to one of 47.25°C, at which point it was promptly switched off and WCC resumed. Quite what it was attempting, I have no idea, and that was the extent to which I wanted to find out.
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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