Ecodan with FTC7 - True Weather Compensation
Posted by: @danwright90I hold off for now with the hardware but i may still get the MELCloud receiver as this would give me flow temperatures as right now, i am in the blind.
Some data is definitely useful. I ordered the internet connection for my Vaillant heat pump and use Home assistant to pick up some basic data because, unlike Mitsubishi, there is no graphical online portal and the app doesn't present much graphically. It has got me out of a couple of holes and proved useful in helping others also!
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
Posted by: @danwright90I hold off for now with the hardware but i may still get the MELCloud receiver as this would give me flow temperatures as right now, i am in the blind.
I would definitely suggest a solution to give you system data is useful, if not essential for identifying issues. I'm not sure what the MELCloud receiver costs to purchase, but the MELCloud app itself is very limited in what it provides. There is potentially one specific alternative option available, which is a dongle device produced by one of the forum users, @f1p, which sells for around £35 and which plugs into the same connection, the CN105 port, that the MelCloud adapter would use.
The information you can get from this, either via Home Assistant, or the MelPump app, is far better for the end user, so it is potentially an inexpensive alternative. For info, the graph data I included in my original reply was from the MelPump app. I was initially sceptical about being able to install it, but had help from @f1p and @majordennisbloodnok via this forum. From your current point of lacking the wifi adapter for MelCloud, I suspect that this might prove to be a better option at lower cost. (NB: just checked and it looks like the Mitsubishi option is around £100-£120 to purchase, so I definitely think this would be the case).
Separately, I think there is a way for you to see real-time flow temperatures within the FTC7 controller, possibly within the installer settings, from memory. I'll see if I can include how to do this in a video clip too. You'll only get a real-time snapshot of the sensors at that point in time, but it sounds like that's better than nothing currently.
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: @danwright90The installers are registered, highly recommended, so i do trust the install.
As you appear not to be too comfortable with how it has been set up, do the installers have anything to contribute?
With the multiplicity of additional controls, I am not sure how the weather compensation performance can be evaluated. It sounds a bit like how I started with all radiators having Tado SRV's
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
I've linked two videos below recorded this evening, one for getting flow temp info and another for you to check that your weather compensation settings are all set correctly (i.e. where the various functions are, rather than copy exactly what mine are doing). Hopefully they're of use as an initial sense check. I've uploaded them via Vimeo, as they're too large to post directly on the forum.
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
-
Struggling to get CoP above 3 with 6 kw Ecodan ASHP
5 days ago
-
Ecodan Zone 2 Mitshibishi thermostat Auto Adapt
1 month ago
-
Ecodan Pump Issues… Circulation pump turns off when heat pump compressor turns off
2 months ago
-
New Mitsubishi Ecodan 11.2kW installation - L9 errors and maybe more
2 months ago
-
Weather compensation- why you should use it
2 months ago
- 27 Forums
- 2,520 Topics
- 58.6 K Posts
- 462 Online
- 6,800 Members
Join Us!
Worth Watching
Latest Posts
-
Issue with a Grant Air Source Heat Pump & Tado Smart Thermostat
Hi all I'm having some trouble with a Grant ASHP and ...
By Renewables345 , 29 minutes ago
-
RE: Underfloor Heating Installation Issues with Heat Pump
We suffered a water leak last year in two rooms and had...
By MartinHook_UK , 40 minutes ago
-
RE: Testing new controls/monitoring for Midea Clone ASHP
Now seems a good time to summarise the costs and effici...
By benson , 49 minutes ago
-
RE: Heat Pump vs New Gas Boiler for Inherited House - Worth the Extra Cost?
*** I now see @jamespa has already posted but will stil...
By cathodeRay , 2 hours ago
-
RE: Tell us about your Solar (PV) setup
@mk4 Charge to 100%, discharge down to 10%.
By bobflux , 2 hours ago
-
RE: Daikin Altherma 3 LT compressor longevity question
This mess is intriguing: I wonder if this represent...
By bobflux , 3 hours ago
-
RE: Connecting Growatt SPH5000 over wired ethernet rather than wireless
The simplest wired option is usually the Growatt Ethern...
By Jonatan , 8 hours ago
-
RE: Peak Energy Products V therm 16kW unit heat pump not reaching flow temperature
ASHPs do have a minimum compressor speed. The minimum h...
By bobflux , 14 hours ago
-
RE: Electricity price predictions
@jamespa And it seems some of the nasty public cloud...
By Batpred , 15 hours ago
-
RE: Jokes and fun posts about heat pumps and renewables
Technology is rapidly advancing. BBC News reported th...
By Transparent , 18 hours ago
-
What matters for flow and pressure drop is internal dia...
By bobflux , 19 hours ago
-
RE: Do Fridges and Freezers have COP ratings?
@editor Thank you all for your replies and submitted in...
By Toodles , 21 hours ago
-
I know and yes. The secondary deltaT wont necessaril...
By JamesPa , 1 day ago
-
RE: Designing heating system with air to water heat pump in France, near Lyon
Just love the way you put it! 🤣
By Batpred , 2 days ago
-
RE: Safety update; RCBOs supplying inverters or storage batteries
Thank you for sharing. So it seems that your Schneid...
By Batpred , 2 days ago
-
RE: Forum updates, announcements & issues
@upnorthandpersonal thanks for the thoughtful, consider...
By Mars , 2 days ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
@mk4 All 21 panels have their own Enphase IQ7a microinv...
By Toodles , 2 days ago
-
RE: Setback savings - fact or fiction?
Great, so you have proven that MELCloud is consistently...
By RobS , 3 days ago
-
RE: Mitsu PUHZ120Y 'Outdoor Temp 'error?
Thanks David & James It almos...
By DavidAlgarve , 3 days ago
-
RE: Surge protection devices SPDs
@trebor12345 - your original Topic about the right type...
By Transparent , 3 days ago
-
RE: Help needed with Samsung AE120RXYDEG
@tomf I’ve been sent this from a service engineer at Sa...
By Mars , 3 days ago
-
RE: Buying large amp bidirectional RCD and RCBO
Yes... I went through this particular headache and ende...
By bobflux , 4 days ago
-
O-oh! Let's take this as an opportunity to 'pass the ...
By Transparent , 4 days ago


