Thanks for the analysis of the capabilities of the various smart TRVs.  Its interesting that Wundasmart and Wiser work by PID, which suggests that, with a bit of tweaking of the PID parameters, it might be possible to turn them into the device we really need for heat pumps, ie one which basically settles at the right level of 'opening', a kind of automated LSV.  However it seems clear from what you have said that nobody, other than Adia, has really got their mind round the ASHP case yet which is why I (and many others) advise against using them at the current time and relying on more simple control approaches or even just pure WC.

Posted by: @madbilly

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At some point I will do a £/degree days cost comparison of smart TRVs vs the traditional approach, but it's unlikely to be a large difference based on what I've seen, so the decision is probably more about convenience and personal preference.

Good luck with this one (but I look forward to reading it)

The problem, as you say, is  that its unlikely to be a large difference.  So far as we can tell so far micro-zoning (in time or space), unless extreme, typically makes a few percent difference to fuel consumption.  In some cases it increases consumption, in others it decreases consumption.  Unfortunately the experiments are nigh on impossible to carry out because controlling the external conditions (unless you have a house in a lab) is impossible, and whilst its possible in principle to model it theoretically (I, too, have tried) the simplifications that are necessary to make the model practical are such as to cast doubt on the results.   Several robust discussions on this forum (for example this recent one, which is a continuation of over two years of analysis/discussion) and elsewhere have failed to reach a definitive conclusion that is applicable other than to the actual system on which experiments have been carried out. 

The solution, I fear, is either properly controlled experiments, which requires a house in a warehouse - these do exist but we dont have access) or 'big data';.  The likes of Octopus have (or shortly will) have the 'big data', whether they will release any meaningful insight we don't yet know.  Those of us with a keen interest (which includes me) are likely to continue our amateur attempts at analysing the situation both experimentally and theoretically, but I am increasingly pessimistic that much further progress will be made.  What is really needed is a couple of PhD studies!

If you did get any useful results out of your heatpunk house model it would be great if you shared them!

Posted by: @madbilly

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I am generally happy with the result, however the bedrooms are always warmer than the living room which I suppose is the point about insulation and the living room is basically heating the rooms above it.

The simple, low tech, solution to this (assuming its a problem) is to turn down the LSVs in the bedrooms.  It does work, honestly!  Disappointing if you like tweaking things, but effective.

I think that most of the others work by PID as well, I just didn't confirm it with tech support. I think a DIY solution is possible using TRVs that expose more control, e.g. generic Z-Wave or Zigbee smart TRVs, but that would require also programming it all - fun if you've got the time!

I'm not sure any analysis of mine will be useful, but I'll share it if I think it tells a story.

The LSVs were already turned down to 1/8th turn open and I realised that there was actually no flow! So I had to turn open to 1/4, and I think I'll find I have to turn down the TRVs (not smart currently) to avoid the rooms being too hot.

Posted by: @madbilly

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The LSVs were already turned down to 1/8th turn open and I realised that there was actually no flow! So I had to turn open to 1/4,

Many lsvs go from full off to full on in a fraction of a turn, they are basically isolation valves.  There is a whole section on this (comparing different lsvs) on the heat geek site.  The property is called, at least by heat geek, 'valve authority'

Yes, I'd read that and already knew that LSVs exhibit a kind of logarithmic behaviour, but knowing it unfortunately doesn't change the actual valves I've got.