History
Feb 25 - 9.5Kw 20 panel South Facing Solar Array and Tesla Powerwall 3 fitted - Octopus Intelligent Go - Best decision ever built up just under £500 credit before winter hit. No issues with any of the kit, other than in ability to configure the Tesla App as you wish and interface issues with Octopus in particular with the Intelligent Octopus. Have worked out alternate strategies to get around most of them
Our Combi Boiler (18 years old) packed up again in July - managed to get 60 seconds hot water - did get a work-around fix but in the mean time decided to pull the trigger and go for ASHP

Received 5 quotes (1 x local, Octopus, and two others) all through the grant - rejected Octopus out of principal very quickly, in the end went with Puraflow. I did have an issue with all the quotes in that they just provide bullet items and then here is your price to pay (less the grant). I have a nagging suspicion that quite a bit of the £7.5K grant adds to supplier’s margin. I fully understand there is design, and lots of extras, so why can't these be itemised? In the end after some negotiation I received and acceptable quote from Puraflow.

Design and Pre-Install - I would rate a 10/10 - had really good design visit and heat loss calculation per room and EPC survey. Received design documents and follow up calls. Install was simple as perfect position for Heat Pump outside back wall, very short run to Garage and Water Cylinder to be placed in position freed by the old Combi Boiler. Heat Loss calculation per room required 8 rad upgraded. Overall, the 162m2 4 bed detached house has just under 8KW heat loss - System agreed was a 10kW Midea R32 - 10 kW - MHC- V10W/D2N8 and 175L Telford Tempest Tank - 47C Flow for a SCoP of 4.2 and Water 50C

Install - 9/10 - total install only took 2 days. Plumbers on day 1 - basic install of the ASHP, removal of old Combi and install of Water Tank and replacement of the 8 radiators. All very good, clean. Only issue that loses 1 mark is one of the new radiators top plate was damaged.
Day 2 Electrical day - all good. System flushed and configured. Retrospective the handover was light and had the same most get - i.e. use Midea thermostat and using schedules to control temp. I thought this was OK and I did not know any difference. All rubbish was removed and house spotless so again very good.

Post Sales 1/10
First problem was misbehaving Midea APP - dropping connectivity with the wall unit - call logged - never received a fix. In end solved myself - will the usual reboot of the wall unit - these fixes it for 5 or 6 days before connection is lost again.

Second Problem is after 4 weeks still not received the replacement cover for the radiator - last promise was delivery Friday. It is minor but irritating. I have received a couple of calls, but my impression is they are focused on sales and not support.

New Problem - I have now been trawling this fantastic forum and know realise I have an inefficient configuration - Note I have been happy with the general function and our house has been toasty and water great and even efficiency not bad. I have frigged my efficiency by using schedules to maximise my overnight 7p, also have 13.5KW to play with during the day, plus whatever the Solar produces. After reading this forum I then checked my COP and noted it was barely 3 most of the time and then I read about Weather Compensation, and this opened my mind.

As per one of the previous posters I learnt how to go into Service Mode and made note of my old settings and edited the curve to be 32C at 14C and still 50 and -2C. Today i bit the bullet and and turned my Thermostat up to 27C and disabled all my schedules so the ASHP will run continuously. So far so good - my small temp gages are sitting at 19.5 C which is perfect for us. Heat Pump taking <1KW per hour and COP reporting over 4 (13C outside so not a strenuous test)

I have not edited anything else, I know there is a setting somewhere you can change the curve. I assume this impact how much hotter the water flow is per 1 C rise in outside temperature. If there is a MIDEA expert this would be great to know. I have found some vids on Youtube. Note I have all rad ITVS set to max and only one zone. We do have a great big wood burner that I have now hardly used!
Puraflow have let themselves down from their previous excellent presales and install service. It is a shame I feel left alone to learn and configure my system.

Have I done the right thing to use a WC curve? Until I read this forum, I was reasonably happy and had never even heard of a WC curve. I am lucky in having the EV tariff and big battery and some solar. This time of year, get about 200KW per month depending upon sun.