@Jenp MisterW is the one with an Ecodan 

You either run the system on the weather compensation OR use a fixed flow temp. Your earlier post suggested you are mixing the two methods, but they are mutually exclusive as he said.

When you refer to 16 and 19 is that flow rate ? Can you give units to clarify?

Yes I believe the flow rate is 16, upon checking the figure’s advised by heat geek,I  read it should be min 19…I have zero room stats apart from the one on the control panel so no idea how I’m supposed to know unless I buy something else to add to system., it’s all very confusing but once I know what’s what and how to set it up I’ll be happier, at the minute I’m just going by what I’ve read/watched and applied methods ad advised.. misterw may well be the one with the eco Dan but I don’t appreciate unhelpful  comments.. if I knew what to do I wouldn’t be asking the questions, giving advice is maybe more useful….thank you for yr comments,

@Jenp the flow rate on my Daikin varies from around 14 litres per minute to 19. LookinG at your COP OF 3.5 (is that for hot water and heating?) I think your system looks fine, and that is what we are getting at the moment. Our heating is returning around COP of 4 but it is the hot water that drags it down - this is running around 2.3 (as expected as it is heating the hot water to a higher temperature)

@jason.lewis have you been able to set your flow rate or is it just reported as 14 to 19 l/m ? 

Thanks Jase, we tend to use the Solar to heat the hot water, unless a cloudy day I’ll put it on an hour or so, depending on what the weather man predicts! I’m not sure how to figure out the cop for both, or individually, I just see the 2 figures and calculate I’m afraid.  I just don’t know whether to leave at curve settings I added or switch back to room stat, but using a lower flow temp. It was at 55 fixed I believe, and whether ( don’t know if possible) reduce the flow temp to like 40 but use room stat all the time… argh it’s so confusing!

 I just want house warm and reduce running costs where possible, 300 p/m with Solar is a lot…thanks all!

@juliamc thats just what I see when (very) occasionally I have reason to be in the airing  cupboard :-)