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!
Mitsubishi Ecodan 14kW ASHP costing £450-£550 per month to run
I'm new to this forum (and any online forum for that matter). I'm at my wits end with an ASHP that's costing over £450 pcm in a new build home (Oct & Nov). December is on course for £550 for the month according to the smart meter. Despite assurances from Mitsubishi and independent experts that I'm set up correctly I can't believe that's true.
I have a Mitsubishi Ecodan 14kw ASHP
Underfloor heating downstairs
Rads on 2nd and 3rd floor in a 5 bed house approx 3000 square foot home.
House build in late 2018.
Please could you point me in the right direction for some advice?
Thank you
Hi, Welcome to the forum. Just a couple of questions to get started.
Was the HP installed when the house was built or was it an add-on after the house was built?
What is the energy requirement as per EPC?
Do you know your heat loss calculation?
What temperature are you heating the house to?
Are the temperatures of the top floor radiators hot?
Posted by: @marknhudsonI'm new to this forum (and any online forum for that matter). I'm at my wits end with an ASHP that's costing over £450 pcm in a new build home (Oct & Nov). December is on course for £550 for the month according to the smart meter. Despite assurances from Mitsubishi and independent experts that I'm set up correctly I can't believe that's true.
I have a Mitsubishi Ecodan 14kw ASHP
Underfloor heating downstairs
Rads on 2nd and 3rd floor in a 5 bed house approx 3000 square foot home.
House build in late 2018.
Please could you point me in the right direction for some advice?
Thank you
Hi Mark,
Do you know how your system is being controlled? Do you have thermostats and TRV's? Is the FTC controller set for weather compensation control? If you are not certain then post a photo of the controller screen.
@derek-m Thanks for coming back so swiftly.
Do these pictures help? We have 6 underfloor heating zone controls on the ground floor as pictured and then a control on the first floor for the rads plus the main control hub in a closet as pictured.
Hi @marknhudson
Please press the F1 button and let me know what the displayed temperatures are reading.
@derek-m Hi Derek, I've pressed the first of 4 buttons but the display doesn't change much. Just showing this...
Hi @marknhudson
Do you know how to check and/or adjust the weather compensation parameters?
Do the radiators get warm to the touch?
@derek-m Not sure but I can have a play around with it. Is there some setting that it should be set to?
Rads get warm but never hot
Hi @marknhudson
Warm is okay, cool is much better for improved efficiency.
It would appear that the 'Information' screen is not available if you have 2 zones set.
Press and hold the 'Menu' key for 5 seconds and then select Heating/Cooling. Press 'F4' key and select 'Zone 1', then press 'F2' or 'F3' to view the actual parameter settings. Since I don't know the heat loss for your home you could try adjusting to the following:-
Set the water flow temperature to 45C at an outside air temperature of -10C, and a water flow temperature of 25C at an outside air temperature of 18C. Confirm the settings, then check the values for Zone 2 and adjust if necessary.
- 26 Forums
- 2,725 Topics
- 63.8 K Posts
- 1,062 Online
- 7,126 Members
Join Us!
Installer Finder
Degrees of Separation
Latest Posts
-
RE: Jokes and fun posts about heat pumps and renewables
@transparent I’ve heard that that is why American cars ...
By Toodles , 3 hours ago
-
RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
Have either quote provided room by room heat loss calcu...
By Old_Scientist , 17 hours ago
-
RE: Heat Pump Servicing & Maintenance – Good Value or Rip-Off?
@old_scientist if you are going DIY then you may wan...
By Papahuhu , 2 days ago
-
RE: Indevolt Batteries UK Support & Info Thread
After a short while that was followed by the 'power war...
By JamesPa , 2 days ago
-
RE: Samsung heat pump - data cable issue
That's well done. Cable is the correct type (LIYCY = 2x...
By bobflux , 2 days ago
-
RE: Electricity price predictions
I agree, we will find out at the next budget whether th...
By Old_Scientist , 3 days ago
-
RE: Missing flow temperature in Heat Geek proposal
@editor I went through HG website, so should be ok for ...
By sttpd1917 , 3 days ago
-
Who did the Freedom Heat Pump cloud server and what did...
By Mars , 3 days ago
-
RE: Who's your electricity provider and what's your tariff?
Reading between the lines of what octopus are doing wit...
By JamesPa , 3 days ago
-
RE: Air to air bus grant installer anywhere
The through wall two hole ones have their place (listed...
By EtchedPixels , 3 days ago
-
I hope it goes ok, Hon can be hard to set up IF the sof...
By Graham Hendra , 3 days ago
-
@clockworks Hi, So there is a big difference between st...
By ASHP-BOBBA , 3 days ago
-
@editor wellvery comprehensive answer. I will get all i...
By Keithb , 3 days ago
-
RE: Advice on my Heat Pump Journey: Old Stone Built Detached Cottage
all good advice I will follow this up
By PaulC , 3 days ago
-
Heat of vaporization of water is 2.25 MJ/kg (0.625 kWh/...
By bobflux , 4 days ago









