As those who have read my blog know, I have an 8.5kW Mitsubishi Ecodan and 300 litre preplumb cylinder with UFH, 155m2 slab, no buffer, no PV. I will in the next few weeks be posting on my blog in respect of how the DHW and heating have performed over the course of 12 months.
DHW over the course of the year, COP of 2.3, a bit higher in summer, lower in winter. Heating COP of 3.5
No short cycling on the heat pump.
Plenty of DHW capacity and fast recovery - despite continuous drawing off of DHW we have not experienced DHW running out or going cool.
I did a cost comparison before deciding on the ASHP set up, including Sunamp and PV, but ASHP came out on top taking into account capital, running, service and replacement costs into account. I'll go into more detail in due course, but thought it worthwhile highlighting that an ASHP is a good solution and works well for us.