Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!
Mitsu Wireless Controller and MelCloud
I have just had a PAR-WT60R Wireless controller fitted to an Ecodan Hydrobox and I would like to compare notes with someone who has a similar setup.
Firstly, the heating is switched off until 1st October, but MelCloud is showing "House Heating" as "Idle", whereas previous to the installation I think it stated "Stopped" or similar. Surely, it should only show "Idle" when in operating mode and having reached temperature?
(DHW is also showing "Idle" outside the timed operating period and I thought this also, previously showed "Stopped" only outside a timed period).
Secondly, the MelCloud "House heating" is currently showing "Room temperature" as 32C whereas the Wireless controller is showing a room temperature as 26C. I suspect the 32C temperature is being picked up from the thermocouple in the Hydrobox FTC6 which is located in an outside Pump Room. I seem to recall that I can change over the selected thermouple in the FTC6 menu, and would appreciate comments.
I haven't got round to looking at the menu yet, mainly because our outside temperature is currently 41C!
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
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.
Yes, "Prohibit" was the word for when switched/ timed off.
So, apparently, my Melcloud is currently wrong for heating and possibly for DHW, but I am not sure if your DHW is currently switched on.
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
@davidalgarve My DHW is switched on.
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.
It would seem that I have a problem (at least one!) in that both my heating and DHW are showing "Idle" when they are effectively timed off and the should be showing "Prohibit"
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
If they are 'off' because of a timed schedule, and this is their time to be 'off', it might be that it is actually in its 'idle' mode. I don't know that for sure, but in my post above, my CH is turned off in the main controller as opposed to a schedule, hence 'prohibit. The DHW is turned on but is showing 'idle' due to the temp still being above the reheat temp.
It will only show 'prohibit' if turned OFF. Not TIMED to be off. So far as I am aware.
I don't have schedules set. It's either on or off 24/7 or in Holiday Mode.
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 am finding it hard to accept that the display should read "Idle" when either the heating or DHW is "OFF", because I am reasonably sure that it showed "Prohibit" for this condition before the wireless control was added. It would also mean that no difference is recognised between "Up to temperature" and "Switched off"
I am still hoping for advice on the second point i.e. the fact that MelCloud (32C) is not reading the temperature of the Wireless Controller in the lounge (26C) and as such it cannot control - see photos.
I feel certain that Melcloud is still displaying the Hydrobox temperature 32C, but cannot recall where this selection takes place in the menu.
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
On the FTC5 I think this requires the dip switch on the control board switched to on when you plug in the external receiver. SW1-8 from memory. It then allows the external room thermostat to control the system.
Well it has now become obvious that the installation of the Wireless Controller is a complete washout.
Almost certainly, Melcloud is still seeing the Hydrobox temperature rather than the room temperature from the wireless controller.
More seriously, the heat pump is running at random times (often during expensive daytime tariff), totally disassociated with the schedule times set on the FTC6. This is mostly heating DHW, but on occasion has been trying to heat the house (when we are experiencing record ambient temperatures!) through towel rail etc, which do not have thermostats.
So a most unwelcome fight to unfold just to get back to where we were before they carried out the work.
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
Update: I have found that the contractor had changed one of the options to "Forced DHW", and this was probably part of the problem. Having switched this off, I am back to logical operation with Weather Compensation and early morning scheduled DHW.
I have not had any offers of support, but I wonder if someone could confirm my thoughts on the correct selection of thermistor for use with the wireless controller.
Operating with Weather Compensation (without any room thermostat), under "Room sensor setting", I have "Room RC1" (single zone) set to "Main Remote Controller". This meant that MelCloud read the temperature in the FT6 but it did nothing.
With the wireless controller in place, am I correct in assuming that, Room RC1 should be changed to read "TH1" and will therefore read the thermocouple in the PAR-WT60 wireless controller?
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
Hi David
We have an FTC7 but the settings seem to be similar to an FTC6. Our room sensor settings are:
Zone sensor selection sets zone 1 to RC1
Zone 1 programme sets programme 1 to RC1 from 00:00 (i.e. all day).
Looking at the FTC6 manual I'd guess Room RC zone select should be zone 1 and the Sensor setting for Zone 1 should be RC1 and a time of 00:00.
Hope that helps!
@robs Hi Rob,
I really appreciate your information, and this appears to me to be much clearer than that which is given in the manual under: "4 Customising your Settings for Your Home".
It seems that I was on the wrong track in suggesting TH1 and now recall that this is the thyrister in the FT6
However, just to be absolutely sure, before I attempt a second installation of the wireless remote, I am attaching photos of the 3 steps in making the settings. (Incidentally, I have left the "Time Zone" setting as was and this seems to be the same as yours, but I don't understand the significance of this in relation to sensors)
I would be grateful for your comments.
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
- 26 Forums
- 2,618 Topics
- 61.1 K Posts
- 849 Online
- 6,993 Members
Join Us!
Worth Watching
Latest Posts
-
RE: Indevolt Batteries UK Support & Info Thread
Thanks @editor , @indevolt-uk Subject to any comments ...
By JamesPa , 5 hours ago
-
RE: Share Your Experiences with Heat Pump Manufacturer Support
@seoras Sorry to hear that. I found Vaillant very help...
By JamesPa , 6 hours ago
-
The Watchdog That Watched and Waited
On 9 January 2026, Consumer Energy Solutions collapsed ...
By Mars , 9 hours ago
-
RE: GSHP Kaput After 16 Years: New Compressor or Switch to ASHP? Advice Welcome
Cool Energy in Grimsby sell ground source heat pumps an...
By DerekDeLeon , 10 hours ago
-
RE: Valliant Heat Pump Settings
Thats arguably a sign of a good installer - they unders...
By JamesPa , 11 hours ago
-
RE: Electricity price predictions
Well, we have so many cases where rain water mixes with...
By Batpred , 11 hours ago
-
RE: Two heating zones to one zone
@profzarkov They arent obviously wrong, but the only...
By JamesPa , 14 hours ago
-
RE: Towns water feed to air source heat pump system
The DHW circuit cant be separated (well it could, you c...
By JamesPa , 14 hours ago
-
Solis AC-coupled 3kW storage inverter
Solis AC-coupled 3kW storage inverterPylontech batterie...
By MartinRobinson , 20 hours ago
-
RE: My NIBE ASHP Nightmare: No Commissioning, High Bills and a Hostile Installer
As @transparent has observed above, this is not bad, an...
By cathodeRay , 21 hours ago
-
RE: The Grid Says Yes.. Until It Doesn’t: Why Britain's Net Zero Push is Stalling at the Plug Socket
As I was reading this article Mars, I was thinking that...
By Toodles , 2 days ago
-
RE: Tell us about your Solar (PV) setup
Installed in May 2011: 16*Sharp 245 W monocrystalline p...
By txmartyn , 2 days ago
-
-
RE: Say hello and introduce yourself
That doesn't sound 'right' to me. The national Smart ...
By Transparent , 3 days ago
-
RE: Growatt battery disconnected
I doubt this will happen, but I will try and suggest it...
By Eliuccio , 3 days ago
-
Understood. That's why I decided from the outset on a ...
By JamesPa , 3 days ago
-
RE: My experience with 3 heat pump surveys: Heat Geek, British Gas & Octopus
On the litigation, I would not go there and definitely ...
By Batpred , 3 days ago
-
RE: Recommended home battery inverters + regulatory matters - help requested
I suppose if your pv inverter packs up, you have a plan...
By Batpred , 4 days ago
-
RE: New Vaillant aroTherm Plus in black - When will it come to the UK?
Firstly check you are using sound power not sound press...
By JamesPa , 4 days ago
-
That’s the solar up and running, I don’t think it’s the...
By David999 , 4 days ago
-
RE: Seeking ideas / information / commiseration - Pure Drive
I agree with @colinc that you can reuse some of it. A s...
By Batpred , 4 days ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
@toodles Im trying me best to ignore orangeman, I figur...
By Papahuhu , 4 days ago
-
@toodles That’s way better per kWp performance than our...
By Papahuhu , 5 days ago









