ReedRichards

I'm sorry but you can't do that either. You can install measuring equipment that will determine your COP and thus your SCOP. At the time my Therma V was installed it was a requirement for the heat pump to have a dedicated electricity meter so I can tell exactly how much electricity my heat pump uses - but I don't think that is done anymore. And my EPC has a very inaccurate estimate of the heat and hot water requirements for my house so I can make an equally inaccurate estimate of my SCOP.

It's usually a straight line; nothing sophisticated.

You haven't misunderstood. The Therma V has all the data to give you a COP reading but it doesn't. But anyway it's really the annualised figure, the Seasonal COP, that matters.

I beg your pardon, @JohnMo? I think he means "not necessarily". Heat pumps have a target flow temperature. But it may take them a while to reach that target. They will indeed shut down if the target is exceeded (by some pre-set margin) at their minimum electrical input. You would try to establish the the minimum flow temperature needed for your desired interior temperature at each particular outside temperature. Once you have done that, you use weather compensation to render it automatic so you can stop playing around.

My OH has a small studio tacked on to the back of our garage, which is external to the house. I've been thinking I should get an A2A heat pump to heat that room; it's only 10 square meters in floor area, although being a garage the walls are not insulated. Any recommendations for a make/model?

I have a few radiators that make some noise. I think the fundamental problem is that you are trying to achieve a 5 C temperature drop across each radiator and this requires a much higher water flow rate than the 20 C drop that is typically used with boilers. This high flow rate can lead to noise. You might be able to throttle the radiator valve to reduce the flow rate and so reduce or eliminate the noise but this will reduce the radiator output so you may or may not be able to do this and keep the room warm enough.

Yes. I only have a 6.5 kWh battery but I charge it up overnight, charge my EV and get my heat pump going, including the DHW which I now heat to 55 C to make sure it lasts the day. All this before 07:00.

Maybe Eon NextDrive 00:00 - 07:00 would work better for you? It will depend on whether you have solar PV and need the good export rate Octopus gives to its import customers.

There is a setting which gives you various control options for the circulation pump. Not all of these (e.g. the option to aim for a particular delta T) are likely to give you a fixed flow rate. Which option have you chosen?

When my heat pump was first installed it seemed to drain randomly from the base but then my installer fitted a small drain pipe to the base that runs to a soakaway and that has worked perfectly.

Maybe you can post a picture or two because your description isn't making sense to me?

I don't think there is a "correct" answer; it's up to you to choose. One might suppose the optimal setting is "Optimal". Or you'll just have to experiment.

Maybe, but then you can't use the Load Compensation capability ("Air + Water").

No. Unless, I suppose, it is an undocumented feature.

Switching 240 V seems like something out of the dark ages but it was the norm for boilers. Just looking elsewhere, it seems a single channel Hive uses voltage free switching but a dual channel Hive (heating and hot water) switches 240 V.