Please remember we are all paying customers, just like you, trying to help each other 
@TrystanLea or @glyn.hudson can you help with deletion of the account
Unfortunately, we canāt answer that for you, because your house is different from our houses. Youāve said you had to adjust the offset when it was -5, 0, 5, -1 but didnāt tell us what adjustment you actually made. Note that changing any of the parameters will change the LWT for all the outside temperatures. They are not independent of each other.
Ideally, you have a table like:
outside temp. required LWT
-5 48
-1 42
3 39
7 36
then we can tell you what values to set for X1, Y1, X2, Y2.
(The offset is sufficient, if you didnāt record the actual LWT - we can infer the LWT from existing curve + offset.)
I understand your frustration, but please stay with us. Everyone who has contributed to this conversation so far had done it in the spirit of good will and self help. Getting annoyed with those contributors wonāt help you, neither will it help the community at large.
If you donāt understand what they are saying, itās not your fault and itās not theirs either. Heat pumps are complicated devices and thereās a lot ā and I mean A LOT ā of learning to be done before youāll be able to understand how yours works and how to set it up to suit your needs.
Personally, I canāt join in to try to explain because I donāt have a heat pump and donāt have the in-depth knowledge required. But I have in the past persevered with people whoāve been at a total loss with using other OEM equipment and, though itās been hard work for both of us, theyāve stuck at it and in the end have learned a lot and been grateful.
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Let me see if I can answer your questions directly and simply:
Reduce y1.
Increase y1.
Reduce y2.
Increase y2.
Leave x1 and x2 alone for now.
Do this gradually over several days, and youāll start to be more comfortable.
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And from what Iāve seen and/or helped with, theyāve been sucessful in their endevor as well.
A certain user who designed his own energy monitor, knew only a little about doing it, yet
managed to make good of it with help from you and me, comes to mind.
Itās a shame that @DrConradInTheHouse hasnāt been back yet. I hope heās not gone for good.
Greetings good folk - finally back!!!
I decided that I was frustrating myself and many of you too, ostensibly down to my ignorance and lack of awareness and investment in on the job coaching.
I have since mentally digested many resources and observed countless videos.
Having now reached the nadir of heating competence (not) I have focused on Weather Dependent Curve (WDC) to drive Leaving Water Temp (LWT) based on Outside Temp (OT). I am not a heating engineer, reading online guides and watching videos isnāt going to make me one, there is so much going on in the operation of the Daikin EDLA04EV23 4kw ASHP monoblock and its internal electronics/mechanics and algorithms, the other units like the pump in the loft and other gadgets that were installed - I dont understand any of these but I have spent time on WDC and the Daikin MMI installer/commissioning and field settings.
I have decided to completely digress from the Octopus install commissioning settings and performed the following in the MMI:
- Set emitter type Fancoil from Radiators to get the 5c dT (it was 10 which is not appropriate for low temp flow systems?)
- Set control method from Room Thermostat to WDC/LWT so that the room thermostat influence is removed (I was getting 4 periods of the day when the house was too hot or too cold). This seemed to be the result of some āoscillationā in On/Off heating.
- After days of tweaking to find the most suitable LWT for a room temp of 20.5C across OT range, I set Y1=44 Y2=25 X1=-4 X2=18. This has managed to maintain a comfortable 20.5 or thereabouts.
However, what I do not understand is the WDC determination of LWT because I crafted the curve in Excel (attached) and dialled in the same settings. At 8C my graph tells me that LWT should be about 33.6C however the LWT reported in the MMI and 36C. I have left it a couple of hours before posting this and itās stayed at 36C and OT has stayed at 8C. Can someone explain what might be going on here?
By the way, the red line is the Octopus install setting, the blue line is mine. (and of course any insight and correction you can offer would be taken in great appreciation)
Octopus needs the systems to give the some comfort as the removed gas boilers on the day they leave the site. Hence the settings they choose.
mmm, not convinced.
where do you get that information from may I ask or is it your opinion? i assert this because it is not what the installation team said, nor is it what the commissioner said or did, and it differs from what Iāve been advised by independent heating contractors.
Iām sure thatās just an opinion 
aside, with respect, thatās not actually anything to do with the question I asked , friend
.
Probably overshoot, itās 4c by default. This is a good thing as it allows the compressor to run for longer. Usually accompanied by a period of it not running, then repeat. So on aggregate the overall heat output should still be about right. As long as your home is roughly the temp you want, then donāt worry about it overshooting the target. Typically happens in milder weather. I find mine only sits at target when weāre closer to freezing.
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Heat loss is linear, I believe, but rad output isnāt, it uses the 1.3 exponent, generally. Isnāt that why weather compensation is ācurvedā so why is the spreadsheet linear?. Is it because its aimed at UFH which is probably more linear than rads?.
ālinearā ? itās the same as the MMI line, and the same in the install manual.
Youāre right, but this heatpump only supports WC as a straight line, which is good enough for most of its operating range.
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@chrisg youāre right - possibly.
overshoot is set to 2c so that might of explained the hike, however, I am monitoring the sensor value and it never drops to the expected value. Itās as though thereās a floor limit where I have not set one and there isnāt one set the MMI ā¦unless itās internal to the monoblock.
As you seen competent Chris and aware of the subject domain, may I just ask another question here of you pleaseā¦
my leaving water temperature is 35C at the moment The inlet plate heat exchanger input is 33 ( I guess thatās the return ) The flow rate is 15 L per minute and the ambient temperature is 7Ā° C, desired room temp reached and stable at 20.5. The pump is on compressor is on booster heater off diverter valve set to heat - space heating. Anything sound abnormal there to you (summary explanations more than welcome 
) my initial observation was the delta T should be 5c but it isnāt, radiators are all been balanced and all the TRVs are fully open.
Thank you for your kind words, in reality I have about 6 months of experience as a customer with my heat pump but Iāll try to help others based on my own observations of my system.
What youāre seeing seems to match my own experience. The heat pumpās circulation pump always starts running at maximum (or whatever the pump limitation is set to in the MMI) for the first 20 minutes or so, only dropping to a lower rate after that point. During that initial startup phase, itās goal is to get maximum heat throughout the system, the result of which is dT being much lower. After the circulation pump speed drops to its stable state, dT should then rise and be maintained at target (usually 5).
During milder weather, overshoot kicks in before the 20 minutes is up so the circulation pump never drops to the lower flow rate and thus dT never rises to target.
@chrisg , once again youāre absolutely spot onā¦
Iāve just checked the temperatures and the leaving water temp is now just 1Ā° above the expected value and the return is 4Ā° less than the LWT so youāre right again.
flow rate down to 7L/minā¦ whyās that reduced from 15 Chris?
You are in danger though of going into my black book of gurus as a GoTo person with all my questions 
There is a relationship between flow rate and dT - that much I can observe. Why it doesnāt aim for the configured dT always, Iām not sure. Thereās probably some science behind the two phased approach but I donāt know what it is. Maybe itās as simple as in the initial higher flow speed phase, it tries to get all rads some heat since some will be a longer path than others? Iām not sure.
Interesting setup and quite low figures especially the -14. I have X1 at 41Ā°C as I have gone down to 39Ā°C but find HP modulates a lot. Still having problems with the ups and downs of the temperature over the last couple of days. Have changed the setting on the Madoka between -4 and +2 to try and get a continuous chart but still not settling down. Am I right it assuming this figure is raising and lowering the leaving water temperature.
not sure who your questions directed to but Iāll query you if you donāt mind ā¦
Youāre another one referring to modulationā¦ I just donāt see this on my day kidney EDLA04 heat pump. Chris is the same he doesnāt see it either. how do you know itās modulating what whereās the evidence can we see it along with any other inputs that might be recording the modulation?
Iāve removed the thermostat control because I found it creates four periods of through the day the same period through the day of overshoot and undershoot until the room gets uncomfortably warm followed by periods of cold . So now I just run a fixed leaving water temperature based on the weather curve and just dial in an offset now weāre getting some solar gain. Iām glad weāve seen the back of -5C temperatures from around here on NW Coast.
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