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!
@richard24738 How about a slightly taller and evergreen plant in a pot where the present one is? 😉 Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
@toodles I guess you are trying to create a bit of shade.
Not sure if the wife will agree to blocking the kitchen window and to be honest, unless it's quite far out from the wall, it wont create any shade.
Mitsi have just telephoned and will visit on the 1st November.
Install 13 April 2024 - 4 Bedroom Brick Detached - Heat Loss 9,281w, Design 45c at -2 - Ecodan 11.2kw R32 - 25L Buffer - 250L Telford Tempest HP DHW - All 16 radiators replaced - Auto Adapt - Mel-Pump app - Octopus Cosy Fixed
10 March 2026 - now 2 x Sigenstor 10 batteries with 8kw Inverter
@richard24738 Sounds like a plan then! Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
Legionairres taking too long: Mitsubishi diagnosed a defective immersion heater. Installer is coming next week to replace it.
Outside temperature over reading: Mitsubishi replaced the outside thermostat under warranty. I have doubts if that will fix the over reading but can't really tell until we get some warmer sunny weather.
Install 13 April 2024 - 4 Bedroom Brick Detached - Heat Loss 9,281w, Design 45c at -2 - Ecodan 11.2kw R32 - 25L Buffer - 250L Telford Tempest HP DHW - All 16 radiators replaced - Auto Adapt - Mel-Pump app - Octopus Cosy Fixed
10 March 2026 - now 2 x Sigenstor 10 batteries with 8kw Inverter
@richard24738 do you know where the outdoor thermistor sits, is it on the back, top corner? Mine sits on a raised balcony but south facing, I'm thinking maybe I could move it to sit just under the raised slabs, probably a less affected area by sunny days.
@boycey Yes, the thermostat on my Ecodan is on the back in the top corner.
When the engineer replaced the thermostat, I suggested that it could perhaps be repositioned so as not to be affected by heat radiating off the house wall.
He poo poo'd the suggestion saying that all ecodans have it on the back at the top without a problem. We shall see!
Shame it's wired and not wireless.
Install 13 April 2024 - 4 Bedroom Brick Detached - Heat Loss 9,281w, Design 45c at -2 - Ecodan 11.2kw R32 - 25L Buffer - 250L Telford Tempest HP DHW - All 16 radiators replaced - Auto Adapt - Mel-Pump app - Octopus Cosy Fixed
10 March 2026 - now 2 x Sigenstor 10 batteries with 8kw Inverter
Just to follow up on the Outside temperature issue.
Last year I reported that the Ecodan outside temperature was over reading on sunny days. An engineer visited and replaced the thermostat. I hadn't noticed a problem since but that has been during the winter.
Today is a lovely sunny day - actual outside temperature 12c - Ecodan Outside temperature reading 22c!
Phoned Mitsubishi and asked if I should be concerned and the answer was yes due to the reading affecting Auto Adapt.
I explained that I hadn't noticed anything during the winter but now with a sunny day, the outdoor temperature reading has shot up.
As my original report of this last year was a warranty issue they want to check the system out again under warranty.
Personally I believe the problem is simply caused by the positioning of the thermostat so it catched the sun from the side and has reflected heat from the wall behind.
Repositioning the thermostat would seem to be the obvious solution but the original Mitsubishi Engineer said no.
Install 13 April 2024 - 4 Bedroom Brick Detached - Heat Loss 9,281w, Design 45c at -2 - Ecodan 11.2kw R32 - 25L Buffer - 250L Telford Tempest HP DHW - All 16 radiators replaced - Auto Adapt - Mel-Pump app - Octopus Cosy Fixed
10 March 2026 - now 2 x Sigenstor 10 batteries with 8kw Inverter
Posted by: @richard24738Personally I believe the problem is simply caused by the positioning of the thermostat so it catched the sun from the side and has reflected heat from the wall behind.
Repositioning the thermostat would seem to be the obvious solution but the original Mitsubishi Engineer said no.
Weird that the Mitsubishi engineer says no. My (vaillant) sensor was specifically placed by my installer somewhere in permanent shade, with no chance of reflected sunlight.
Perhaps you could try rigging up a temporary shade and observe what happens to the output figure!
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.
@jamespa Unfortunately it's now in the shade.
The outside temperature is now down to reading a more realistic 11c so I'll have to wait for another sunny day!
Big drop of 11c from in the sun to shade.
Install 13 April 2024 - 4 Bedroom Brick Detached - Heat Loss 9,281w, Design 45c at -2 - Ecodan 11.2kw R32 - 25L Buffer - 250L Telford Tempest HP DHW - All 16 radiators replaced - Auto Adapt - Mel-Pump app - Octopus Cosy Fixed
10 March 2026 - now 2 x Sigenstor 10 batteries with 8kw Inverter
Posted by: @richard24738@jamespa Unfortunately it's now in the shade.
The outside temperature is now down to reading a more realistic 11c so I'll have to wait for another sunny day!
Big drop of 11c from in the sun to shade.
... but suspicious it correlates with it getting shaded. 11C isnt particularly surprising. Hopefully its white in colour, if it were black it could easily be double or treble!
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.
James: Just noticed the timing of the drop: from 21 c at 16:05 to 10c at 16:45.
Install 13 April 2024 - 4 Bedroom Brick Detached - Heat Loss 9,281w, Design 45c at -2 - Ecodan 11.2kw R32 - 25L Buffer - 250L Telford Tempest HP DHW - All 16 radiators replaced - Auto Adapt - Mel-Pump app - Octopus Cosy Fixed
10 March 2026 - now 2 x Sigenstor 10 batteries with 8kw Inverter
- 26 Forums
- 2,607 Topics
- 60.8 K Posts
- 552 Online
- 6,967 Members
Join Us!
Worth Watching
Latest Posts
-
RE: End-of-Life Heat Pumps: How Do You Dispose of an ASHP in the UK?
Your topic raises my interest for a couple of reasons. ...
By DavidB , 10 minutes ago
-
@batpred frost protection £632 ??? That is taking t...
By MartinRobinson , 31 minutes ago
-
RE: Indevolt Batteries UK Support & Info Thread
@editor Interesting questions. If the answer to either ...
By ChandyKris , 43 minutes ago
-
RE: Renewables & Heat Pumps in the News
@editor, I hear that too. I can confirm that out of ...
By ASHP-BOBBA , 8 hours ago
-
@derbygraham fully agree with James, and it’d be good t...
By Mars , 9 hours ago
-
RE: Microbore heat pump installs
In principle you are almost certainly right, but in pra...
By JamesPa , 10 hours ago
-
RE: Electricity price predictions
@old_scientist We are a low mileage home, so bulk of ou...
By ChandyKris , 11 hours ago
-
There are just too many unknowns for me to comment on p...
By Transparent , 13 hours ago
-
RE: What is the main ‘dictator’ of Agile’s unit price?
@toodles I keep an eye on wholesale prices and energy m...
By ChandyKris , 14 hours ago
-
RE: Brand and installer questions for ASHP
Strange, perhaps it doesnt use modbus which the third p...
By JamesPa , 16 hours ago
-
RE: Upgrading my system, how far do I go?
For comparison, my PW3 with 11.04kW inverter, will char...
By Old_Scientist , 18 hours ago
-
RE: Changes to Tesla Powerwall Charging Regime?
Elon gate - legendary! I take my hat off to you @toodle...
By Old_Scientist , 22 hours ago
-
RE: Mitsubishi Ecodan not good enough ?
Thanks @goody, appreciate the feedback and sorry you ha...
By marcexec , 1 day ago
-
RE: Minimum and Zero Disrupt Heat Pump Installations
True (first sentence) Thats the reason to consider th...
By JamesPa , 2 days ago
-
RE: High air source heat pump running costs – Vaillant AroTherm Plus
Quite right. I was using a rough guesstimate of doublin...
By Majordennisbloodnok , 2 days ago
-
RE: My Grant R290 9kW Heat Pump Installation
Again, really don't know how accurate this is! &nb...
By petch , 2 days ago
-
RE: MCS Quality Audit – Has Anyone Had One? Did It Lead to Remediation?
@toodles The whole scheme is a shocking waste of money....
By Papahuhu , 2 days ago
-
RE: Anyone concerned about GivEnergy?
Many thanks for your, and the subsequent, answers tk qu...
By KevH , 3 days ago
-
RE: DIY or Don’t Touch? Solarman Smart Meter Install
Yes, and these guys would probably be my preferred inst...
By Batpred , 3 days ago
-
RE: Hot water tank lose heat rapidly on random days
@jamespa Hopefully their reasons are well intended! ...
By Bash , 3 days ago
-
RE: Ecoflow UK Support & Info Thread
As mentioned above, we’ve got our full review of the Ec...
By Mars , 3 days ago
-
RE: Say hello and introduce yourself
@sonosppp welcome to the forums. I see you've posted in...
By Mars , 4 days ago
-
RE: Guidance with installing a new heating system
@bobflux Great, thanks for the advice. The pipe has an ...
By Hamilton , 4 days ago
-
RE: Daikin Altherma 3 LT compressor longevity question
@optimistic-optimiser I have has a Daikin for a few yea...
By madsid , 4 days ago
-
RE: UK DIY Battery: SEPLOS 48V 200Ah x2 + Sunsynk 8K – Safe Installation for Garage Conversion
The rule of thumb is to ensure that you can isolate any...
By Transparent , 4 days ago



