@matt-drummer remind me have you got any modulation active , and are you on pure weather comp
I was thinking if turning modulation off next
I have no modulation, not possible as I donāt use the Madoka at all.
No room temperature control apart from me and the weather!
No wdc either.
Just fixed lwt that I adjust from my telephone as I see fit, which is not very often, normally just when it is out of control!
But I donāt even do that anymore.
If I am not happy with the flow temperature I just turn it off, set it to what I want and then restart.
Mainly actually if I want to turn it down, it tends to ignore the request for some time, turning it up when running isnāt so much of an issue, but if it doesnāt do it more or less straight away, I turn it off.
Generally though, I just set it and leave it, stopping space heating only to do DHW.
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Intresting , have you got a link to your system
You havenāt looked before?
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Iāve looked at many 
What is you location so I can look at a little more
Sadly, Ipswich 
My temperature sensor is in a bedroom, only place it works.
It is about 2c warmer downstairs.
Itās quite good really as I can see downstairs from the Daikin app and upstairs from this when I am at work. Just to make sure nobody at home is cold.
I forgot, I am also running in quiet mode (quietest) and have been for a week or so.
Hi @Chris_Hill
As I see it quite a few of us have sub-optimal situations at the moment.
I happen to think itās OK, and as @Timbones has said, itās swings and roundabouts. After all, your heatpump may not be very efficient right now, but it is maintaining your set temperature.
This cold snap will only last a few more days and then the 2 issues ( low CoP made worse by frequent cycling) will melt away with the frost.
In the milder weather through the rest of the year we will be pleased to have the smallest possible heatpump because we will have lower energy consumption than if we had larger pumps.
But what to do for the next week?
Your idea of using the immersion heater sounds a reasonable way to avoid cycling and room heat loss during DHW cycle.
And how would it be to dial down everything by, say, 2 degrees? The house would be cooler, but if the flow was cooler too then the defrosts might be less frequent.
I see your room temperature is recorded at 21.5 where mine is around 19.5 and Iām still comfortable:-)
Cheers, David.
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I expect the difference between measured power on the monoblocs and splits is what is included in the measurement. Maybe the pump isnāt included on the splits. for example, or maybe itās the heating tapes. On a EDLA09 monobloc Iāve seen 828W minimum, only occasionally, and typically the minimum power is over 900W.
Otherwise, itās errors - but the splits do seem to report lower minimum power draws.
I just think it would be odd if Daikin are using a different compressor on similar output heat pumps.
Weāre at -3c outside right now and itās been subzero since midnight.
Thereās been about 12 defrosts in 10 hours.
Indoor temp has been maintained at 19c (the setpoint).
Due to the regular defrosts, itās really tricky to determine the steady state heat output now.
I didnāt think it would frost up this much at a fairly cool indoor ambient temperature. Itās not like weāre pushing it for 21c or something.
I imagined that a steady state, ālow and slowā would be a much more common event in the heat pump world. It seems like they have a knife edge for optimal operating conditions, at least in the UK.
Iām now wondering whether moving to an 8kw for optimal running during most of the year is right, or the extra capacity of the 11kw for the few days we get sub-zero temperatures. Makes me wonder how anyone gets the rated capacity out of the higher units in the ranges. Can the 8kw really do anything close to that? From this thread it looks questionable. I assume the 16kw canāt get anywhere near close to that either without defrosting every 10 minutes.
We have 6 independent heat sources here with 5 of them being A2A heat pumps which were doing the heating for the last 2 years quite well. Just noisily, and draftily and not in every room. So if need be, I could press some of those into service.
Iāve also been running at 60% pump speed. Iām testing today with it back to 100% to see if it changes the behaviour any (other than making additional noise). But certainly we were getting plenty of defrosts here at 60%.
This seems fine and reasonable to me. Iām watching 5 kW Vaillant do exactly the same and my oversized 11 kW Mitsubishi is defrosting almost hourly. As you say, this is only a problem for a few days each winter, and your house is still maintains the set point.
This may help a little, as it reduces power, and slows down the build-up of ice. The effect may be too subtle to see though.
Thanks!
Iāll leave the pump at 100% until tomorrow - overnight lows are forecast to be the same so Iāll have a reasonable comparison.
If the calculated heat output figures from ESPAltherma are to be believed, it was producing 9kw briefly before ramping down to about 5kw from an input power of 3.5kw down to 2kw. Flow target was roughly 40c and dt5 was being met.
Iām sorry, I donāt have the same Emon graphs you guys use.
I do not think they are the same. If you look at the circulation pumps chart, the monobloc is a lot more powerfull, for example.
I mesure total power draw with a CT clamp on the HP supply, at the consumer unit. It accounts for both the internal and the external units.