Daikin or Panasonic ASHP?
Hi everyone.
I read that the design of an ASHP system is more important than the choice of ASHP manufacturer but would like to ask if anyone has any strong opinions either in favour or against the recommended units.
My heat loss survey comes in at 8.5kW and the installer is proposing either Daikin or Panasonic units.
Outside design temperature for my location is -4 DegC. System will be teamed up with a 250l cylinder. No buffers or volumisers required. Anti freeze valves instead of glycol.
Choice is either a 9kW Daikin Altherma 3M or a 9kW J series Panasonic T-CAP.
MCS specs quote slightly higher SCOPs for the Panasonic at any given flow temperature. Also the dimensions of the Panasonic unit fit better in its outside location.
My preference is for the Panasonic unit but any experience on this forum to say yay or nay?
Assuming that I don’t fit any third party monitoring systems or software I would like a decent experience with standard apps and hardware.
Thanks.
We have an estimated heat loss of 6.5 kW (according to the Octopus survey) and very good insulation under the ground floor, in the walls and in the loft plus double glazing in our 4 bedroom semi 1930’s build. Our EPC came out at C and with a few suggestions that we have more than complied with should now be a B.
The 8 kW Daikin EDLA heat pump did us proud last winter when we were experiencing -7 or -8 degrees for a few days and, at peak demand we were consuming~ 40 kWh ish per day to keep us toasty at 22.5 degrees C. 24/7 though our water heating is handled by a Sunamp Thermino ePV210 as we have 8.1 kWp. of solar PV and an Eddi diverter. The Diakin has as I mentioned, done us proud and runs more quietly than the ambient noise in our back garden. We have been with Octopus and at various times been on Agile tariff and now Cosy and with Powerwall storage, this works well. Regards, Toodles.
Toodles, he heats his home with cold draughts and cooks his food with magnets.
Posted by: @thebinmanPanasonic
I don't have one, but everything I have read (lots) point to them being easy to live with, very well built to high spec, seem to work very well out the box. When mine needs to be replaced that's what I will install.
Posted by: @thebinmanI would like a decent experience with standard apps and hardware.
Once up and running nothing to fiddle with - why do you needs Apps?
Maxa i32V5 6kW ASHP (heat and cooling)
6.5kW PV
13.5kW GivEnergy AIO Battery.
@project_electrify I believe that the Daikin 9 kW is a repackaged 16 kW unit. That means it will struggle to modulate low enough, leading to cycling and inefficiencies. That's why a lot of people try to get the 8 kW Daikin instead of the 9 kW when it's a close call.
I'm not 200% sure though so best to double check!
CEO and co-founder at HavenWise
Posted by: @thebinmanI would like a decent experience with standard apps and hardware.
Once up and running nothing to fiddle with - why do you needs Apps?
For apps I’m just meaning for something on my iPhone that can give me some visibility of the ASHP and a few controls.

Even in a perfectly set up system there are occasional curve balls.
As an example, when Octopus announce a saving session we do two things; we opt into that session and we set the timer to turn the ASHP off for that hour or so and then back on again. Since the saving sessions are completely arbitrary from a customer point of view the only way we can do this is by using the apps.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
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