Hi Glyn,
It’s early days so I feel I need a bit more time to get on top of it confidently.
I maybe should make a separate thread about Octopus in due course but I need more data first I think.
The first problem I have is with the information available from the Daikin system, you just have no idea what is going on, it’s not very detailed and not really instant.
The controller is good and the app is ok for controlling the heating, but that is it, not useful for getting the most out of it in terms of efficiency.
I have our house quite warm, but I can afford it and like it, more expensive and less efficient than I could make it but I like it so far.
The heat loss survey from Octopus was pretty good, we only had to change two radiators and there were no additions but the temperature around the house is nicely balanced, slightly cooler upstairs and the living room is noticeably warmer than the rest of the downstairs, but it’s nice.
They had set it up with a constant flow temperature of 50c controlled by the Madoka room thermostat, not great.
I changed it to weather compensation initially with the upper limit controlled by the room thermostat.
The next day I put it on pure weather compensation which improved my COP but I encountered a problem when we went to bed, no way to set back the flow temperature as no scheduling was available, I would have to do it manually.
I need to look at this as maybe there is a setting that I have missed.
So on Sunday evening I put it back to room thermostat limited and I am actually happier with this.
I have a schedule set each day so from 05.00 it is 21c, then from 13.00 it goes to 22c and then from 18.00 it goes to 23c. At 21.00 it goes to 16c.
This ties in a bit with my Octopus Cosy tariff.
Then in the app I have gradually been reducing the flow temperature from the weather dependent curve to get the heat pump to run as long as possible.
I think you can see my data and I have just made it public.
I did the plumbing myself for the heat meter as I couldn’t get anybody to do it. It was an easy job, just access and placement was a little limited but I have over 30cm of straight run to the heat meter.
I don’t think I have any flow problems or air in the heat meter.
I don’t seem to have any short cycling?
I will keep knocking back the flow temperature from the weather dependent curve until I can’t reach the set room temperature.
This is my plan. I am now at minus 5c from the curve I set.
I need some more colder days to see how it works.
It was really cold on Saturday and Sunday and not the easing into heat pump use I was expecting!
But we were not cold and it didn’t costs a fortune so we are happy.
Sorry for the longish post but heat pumps are not easy!
If anybody has a Daikin Altherma 3 installed by Octopus that they need help with I am always around.