Is your error log showing some U2 errors ? check the error history on the main controller
No. There are some P8 errors. All in the same 20 mins though. Its when I turned down heating while at work and then tried to put it back on when I was on my way back when it was unseasonably cold like -7 degrees or something crazy.
The unit is new too if that gives you any info. Had it installed Dec, week before xmas.
The discharge temp starting at 12:30 and 13:30 seems a bit high (90c?) for the compressor frequency (40hz-50hz). Might be a good idea to ask what other owners have for discharge temp with R32 refrigerant?
@ajdunlop
Ah so yours is also high, but somewhat higher frequencies. You also have R32?
your cop is also no that good? Probably because of the DHW sessions (Iām not used to see all these sub 3.5 COP 
)
For example hereās last night, quite cold. But I have underfloor heating and can use low (26c-27c) feed temp.
Yes I have Quiet Mode on so thatās why it goes up to and sticks with 60Hz quite a lot.
Its a 8.5kW R32 (PUZ-WM85VAA).
How accurate are your COPs? Are they just estimated from the FTC values or do you have proper heat metering? I find quite a large difference.
It looks like the heating COP during that period was around 2.7 which is a bit naff but the outdoor temperature was around 0 or just below. We have radiators that are a bit undersized so currently are running with flow temperatures of about 42-45Ā°C. Also parts of our house are very well insulated and airtight but other parts are most definitely not so take quite a bit to keep warm.
Our hot water runs have been very messy over the last few days as outdoor temperatures have been low and defrosts have come along at just the wrong points.
I think our normal runs would have a COP of about 2.9.
My main issue with hot water is that our tank isnāt big enough to get away with a single warm up so we have to reheat as needed so it isnāt necessary in the right part of the day for higher outdoor air temps and the whole tank may not be depleted.
I may try going back to to 2 scheduled runs one in cheap morning electricity and the same mid afternoon, watching out for those days where everyone decides to have a shower in the evening rather than a split.
I also get a weird thing that sometimes happens when itās cold and there is a DHW run where the output energy drops to nothing but the compressor is still taking energy. This can be seen after the defrost at around 8:30.
Thankfully around just before 9:00 it looks like someone had a shower that caused it to be able to recover.
This happens much less often now that I have added thermal paste to our tank temperature sensor.
For consumption I use this Order the kWh Meter 3-phase MID in our store - HomeWizard. Itās a certified energy meter, so I trust that one. To be fair, the ecodan is over reporting itās usage. I have compared the heatpump numbers vs actual meter and the ecodan is always overreporting. So the COP numbers via the heatpump would be worse.
For heat output I calculate the realtime output via flow rate / 60 * delta T * water constant (fitted)
The daily totals match with the totals in the heatpump. The produced number heat from the heatpump is pretty decent (ppl compared it with kamstrup).
I think my COP calculation is pretty decent.
Your COP is of course largely determined by your feed temp and radiators. If I was running those feed temps, I probably would get sub 3.5 COP as well.
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Mine is 5kW but yeah I have all radiators up and downstairs - So higher flow temps than the underfloor.
I used to use FTC flow and return and then calculate COP myself on Home Assistant but Iāve installed my own DS18B20 sensors fed into ESPHome and Iām getting more accurate (and slightly better) COP now as the .1 degree accuracy makes a decent difference. Dropping my flow rate has improved things too. For the energy I use a Shelly Pro clamp which is accurate.
I might move to quiet mode. Stop it jumpingā¦
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COP does seem to be quite a bit better after lowering flow rate. Today given a large temp jump is a bit of an outlier so canāt really gauge anything today. Installer planning to come friday now to take a look.