Getting Flow Readings

Weather Comp Settings

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

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.

Thanks James

I 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!

This is the part of your query that is currently puzzling me, as none of these modes are familiar to me from someone who has played around with the FTC7 on a regular basis.

I'm away from home currently, but will take a look this evening to see if I can find the settings you're referring to, and I should also be able to record footage to point to how I can set up and amend the WC curve from the FTC7 screen.  This sounds like it might be useful to figure out where the differences in set up currently are.

Thanks for the reply

I 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 read in other forums that consumption values may not be correct, hence the low COP and true measurement is to place energy monitoring. 

For Grant system in Ireland, the system must be setup on two zones (dont understand the logic)

The installers are registered, highly recommended, so i do trust the install. 

I may need to give it more time with the curve and dialling in the settings to get a more complete picture.

When i started this project, it only seems to get more confusing. 

Logically that means the challenge is a configuration issue to get it to run in weather compensation mode, and that should be feasible with the collective experience within this forum ...

For now, I would hold off from purchasing any additional hardware until such time as we collectively fail to overcome the configuration challenge, as I currently don't see that it's needed.

Very much agree with this!

Sometimes the way to get things to operate in pure WC mode is to set the curve on the controller, then just turn all the 'room temperature set points' (third party and if necessary on the controller) to max.  The heat pump then thinks that the demand isn't satisfied, so keeps pumping water at the WC setting which is what you want.  To get this to work you would of course need to ensure that there is no adaptive mode (where the heat pump modifies its own WC curve) operational.

Without an FTC7 in front of me I probably cant add a lot more, but for sure (well 99.9%) there will be a way to do it.

Thanks for the reply. 

Mine was fitting in May 2025 but i do not have the MELCloud/hardware to get any readings from the system. I purely down to the FTC 7 Controller on the tank. 

The system is running WC and has outdoor temperature sensor but internally, i do not have any wireless ecodan thermostats in place in each Zone. 

The only way to control the heating is with Zone value controls which is linked to the heat pump which signal ON and OFF if there is demand for that zone. 

Looking at the Zone settings on FTC 7, it does use FTC 7 thermostat to balance the curve/flow temp. 

The real issue and with help ChatGPT, Because the location of Tank/FTC7 thermostat is place in warm area, it going to have negative effect COP which currently is 2.5.

To increase the COP, ideally an wireless ecodan thermostats should be place in each zone which will give a more accurate temperature reading of the house/zones.

What i am trying to nail down if others has experience this, is the FTC 7 thermostat sensor having a bearing/impact, is further settings need to be updated or more hardware to help the system work better

First of all, be very cautious about the relying on the reported COP figures, in isolation of anything else as an indicator of a system problem, as with each experience I read from fellow Ecodan users, I'm increasingly of the opinion that the true COP is potentially being under-reported.  Virtually all the posts I see regarding Ecodan performance have figures in the 2.5-3.0 range.  I'm struggling to get mine above a SCOP of 3.0, and yesterday it ran at a COP of 2.54 for heating in outside air temperature of -1.6°C.  Allowing for the fact that any heat pump will become less efficient as the weather gets colder, these are still low numbers, yet I'm seeing cost savings of around 55% on energy consumption compared to the equivalent gas boiler costs from last year.

Faced with the two possibilities of "Ecodans are terrible heat pumps" or "Ecodan reporting is understating the COP figure" I'm leaning increasingly toward the second of the two, albeit I'm very conscious that it's just a personal theory for now.

In your scenario, I'd be cautious about adding the Mitsubishi remote thermostat controllers, as you already have 3rd party ones in place, and the Mitsubishi ones are unlikely to be any more accurate than these, as they only report in 0.5°C increments.  The challenge you appear to have is that the system is installed with 3rd party thermostats, and that there are more than one of them, so the system setup is intended to be operated as two separate zones.  All of this puts barriers in place to the intention of running with weather compensation, which ideally should be run as a single zone throughout the house.  Adding Mitsubishi thermostats in their place would simply be switching the room reporting function from one device to another, but wouldn't help generate any improved efficiency in isolation.

Based on your comments, my interpretation is that the Ecodan specific cylinder you have is designed to have the FTC7 controller attached to it in that location, so this being next to the cylinder itself is presumably pre-designed by Mitsubishi and not intended to act as the primary indoor reporting thermostat for the system.  Logically, the installation should have included one of the portable Mitsubishi devices for that purpose, but your installer has used two 3rd party ones in place of this.  These look to be reporting devices only, so are not capable of sending data back to the FTC7 for it to use, so the FTC7 is defaulting to it's own sensor in the absence of this.

Consequently, if you want to be able to have better control over an internal temperature driven heating system then replacing the two 3rd party thermostats with a single Mitsubishi portable thermostat would assist with this.  However, this isn't what you are looking to achieve, based on your comments, as you want to operate on pure weather compensation.  To do this, you have everything in place already, as you have the outdoor temperature sensor, which is all that it should require.  Logically that means the challenge is a configuration issue to get it to run in weather compensation mode, and that should be feasible with the collective experience within this forum, of which @jamespa is ultimately one of the keenest minds, but doesn't have direct experience of the Ecodan heat pumps, so perhaps myself and others can provide this user insight as and where it's needed.

For now, I would hold off from purchasing any additional hardware until such time as we collectively fail to overcome the configuration challenge, as I currently don't see that it's needed.

Thanks for the reply. 

It is trying to navigate/understand what the system is doing internally and if the FTC 7 thermostat is having an impact.

The FTC 7 does have DIP switch on board if 3rd controllers are being used. I wonder, if that is the case, is the FTC 7/heat pump running in pure weather compensation mode ? 

The signal from zone controllers/thermostats is in place but heat pump will run when the WC curve is met.