As mentioned, Daikin have a couple of air to water monobloc (all in one) units these days:
EDLA (heating only) or EBLA (heating and cooling) 9/11/14/16 badged models - we believe that the fan speed, maximum electrical input power and compressor max power are all that differ between the models, and therefore all share the same characteristics.
They also do a smaller unit: E(B)LA 4/6/8 model designation.
A number of us have had very poor heat loss surveys to be honest.
If you have the time and the skills, it’s well worth getting to the bottom of what your heat loss actually is.
You can model it using for example the MCS calculator, HeatPunk software, HeatEngineer software and many others.
You can try and measure your heat loss if you have half hourly gas meter readings, known internal temperature and pick a date that was particularly cold but not abnormal (ie you’re after the design temperature). Add up all of your half hourly usage in kWh, remove say 10-15kWh for DWH usage, and divide the rest by 22 hours (to allow ~2hrs for DWH recharge), and then by ~85% to allow for energy lost up the boiler flue.
I think you’ll be surprised how low the figure comes out at.
The other alternative is to try and keep a constant temperature for 24hrs, start tracking the produced space heating heat and also the known internal + outside temperatures, and then working out heat loss from those figures.
Unless you’re seriously out on the heat loss figure in real life, it’s best to focus on understanding how your unit works (best!) and seeing if LWT or Madoka control is best for you and your family.