Hi all
Firstly, massive thanks to Matt, Trystan, Colin, Marko, Vinny and HydroSam for their work, analysis and instrumentation. As the owner of a EDLA09D3V3 HP, installed by Octopus along with larger radiators, I’m very interested in getting the settings optimised for electricity usage and efficiency. I’ve posted a question about P1P2 monitoring on another related thread from Matt.
I’m currently running using LWT mode only - I have to get Octopus back to move the badly placed thermostat, and I quite like not allowing family to mess with it! I am monitoring some Daikin Cloud data using a HA plugin, which only provides what the Cloud API has e.g. none of energy produced, return flow temp, flow rate and so on, but it does give me LWT, Outside temp, LWT Offset (setback) aka Target Temp. LWT Overshoot is 4deg. Family Room Temp is from a Tasmota DS18B20 in the room the thermostat should be in 
- you can see it’s incredibly stable.
You can see the compressor/pump cycling more/less as the Outside Temp varies up/down. I have DHW on schedule, and you can see the legionella cycle on Friday morning 2am - I should also move that to daytime, to improve COP using daytime temps, except it uses the cheap Octopus Flux power slot.
I’m trying to understand what is happening with Matt’s Daikin, and here’s my precis of my situation vs. his, to confirm my understanding:
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9kW HP only reduces output by 40% i.e. from 7.5kW with defrost to 4.6kW minimum (from Colin)
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My Octopus-calculated radiator output at the various room temps for 50/45 flow/return is 9.8kW (Ive checked this from Stelrad figures), but when adjusted for a flow/return of 32/27 for 12deg Outside (WD curve says 29deg + 4deg overshoot), they can only emit about 2.3kW
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HP has to cycle to keep flow temp in required range for current Outside temp…
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Consequent reduction in COP!
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Matt has a similar problem, which he’s going to install bigger rads to fix
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COP is EnergyOut/EnergyIn, so actually allowing the full 4.6kW to be continuously produced for the same energy input means the COP is better…
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But my house is pretty warm with the current output; maybe I just live with the reduced COP because getting a better COP just for the sake of it, given I’m going to use that electricity either way, seems a bit pointless!
Is there something I’m missing/wrong about here, pending further instrumentation and analysis?