@morgan yes, I don’t know why it reads hourly temperature when it should read “temperature history”. I hope you are now seeing the correct graph lines. I guess it may say hourly temperature because it is divided in to 24 hourly divisions.

@sunandair 

The Ecodans just do not have a meter-grade electricity monitoring capacity. There is an over-estimation of the daily consumption that is not consistent, so not easily accountable for. I have a record of accurately measured values of the consumption of my Ecodan, a meter on the supply to the outdoor unit which also then feeds through to the packaged cylinder. If I take the daily measured values and chart them against a calculated value for the difference to the reported consumption figures from MelCloud it produces the following:

Although there is a broad trend for the overestimation to increase as the consumption increases, the linear cluster on the left shows there is a similar range of overestimation even when the actual consumption is only the 600Wh or so that the FTC itself is using when no heat is being generated. Overall for 2023 the difference between measured and estimated consumption is 664 kWh - or 17% of my total energy usage.

My example might be usefully typical, or it might not; I have read others' estimations which are different. So although there is an option in the settings to increase or decrease the value recorded for the energy input in percentage terms, without a benchmark measurement to derive that difference it would just be guesswork. And there would still be a varying amount of inaccuracy day to day.

I don't think there is a simple setting adjustment or mis-programming where controller is applying a spurious correction factor for pumps that may not exist, there are plenty of adjustments that can be made in the settings to account for what hardware is attached to the unit. But Mitsubishi themselves state if you want accurate energy measurements you have to add an external meter - they have not added the electronics to do it within the unit.

@harriup thanks for your post it’s good to get a different perspective on this consumption challenge. You have done a lot of work in gathering MELCloud vs actual data it’s very relevant to my question. Thanks for the post. 
you are right I was hoping for a magic variable and in many ways that’s what you’ve posed in your graph. But as you suggest in your post this may or may not be comparable with other ecodan setups.

My motive for this line of thought is that there are many people who come to this website and who don’t have any metered data and are only looking at Ecodan estimates. Very often puzzled and a little panicked by the perception of unreliable information.

With practise and experience I am happy that you can interpret efficient operation from problematic signs just from the raw MELCloud data but I think this is a big ask to a new owner to do the same when there are signs of inconsistent data.

I apologise for the late reply but have been away for a few days.

thanks again for your post.

@sunandair Hi there, really interesting experiment! So if I understand correctly, your conclusion is that nightly setbacks actually save energy (and therefore money assuming fixed tariffs) for your specific property? And on some days quite a bit actually! All these experiments were run in in Auto Adaptive mode?

Have you ever tried to write some code to automate the optimisation? 

Posted by: @hcas

↑

@sunandair Hi there, really interesting experiment! So if I understand correctly, your conclusion is that nightly setbacks actually save energy (and therefore money assuming fixed tariffs) for your specific property? And on some days quite a bit actually! All these experiments were run in in Auto Adaptive mode?

Have you ever tried to write some code to automate the optimisation? 

Hi HCas

yes, I’m glad you’ve found it interesting. There appears to be a roughly 3 kw saving per night on a 10kwh day and a similar saving on a 15 KWh day but when the auto defrost is operational and freeze stat function is active the savings become quite large. This I believe, is because the set back period overnight doesn’t have any, or so many, defrost cycles. Even when the  auto reheat kicks in the freeze stat function is a gentler output so often doesn’t evoke a frosting up of the fins and usually finishes before a full defrost is begun. 

The earlier tests up to 14th January were mostly weather compensation mode Andy after 14th January we switched the trial so over to Auto Adaptive mode.

I haven’t looked at coding anything since the reason for these trials was to help people with minimal knowhow and basic factory fitted technology. This imo should be everyday products for everybody’s access. But you’re probably right there needs to be improvements in what’s delivered.

Thanks SUNandAIR!

3 kWh on 10 or 15 kWh is substantial, and more than I expected to be honest. So I guess for you the setbacks are now the default?

Is your Ecodan wifi enabled?

@hcas yes we are pretty much settled with a 3 C setback each night now. There could be several reasons for saving energy on a night time set back; not least because night times generally are colder, especially on clear sky nights, so operating a heat pump at night is the most costly time to operate a heat pump. Regarding the Ecodan connectivity, it does have wireless connections and the MELCloud app is part of the Ecodan connectivity. But I also think Mitsubishi somehow control what third party devices can access the op system and appear a little guarded in what parts are accessible.... I think so anyway? There appears to be a bit of technological rivalry between manufacturers which may spill over into limited integration of new devices. 

You may have heard of the Homely system? It is interesting that it isn’t accessible with Mitsubishi and their Ecodan HeatPumps as yet. But I’m not sure if that is Homely being selective or if it is Mitsubishi trying to monopolise how their systems are controlled.

It would be good to know how open and progressive these heat pump manufacturers really are.

@sunandair Yes good point on the temperature during the night and impact on the heat pump efficiency! I've seen similar effects in some simulations I've done. In some instances for instance, if temperature is expected to drop, sometimes it's better to pre-heat a little bit when temperature is still high.  

Yes I've come across Homely. Not sure why they are not compatible with Ecodan. Could be a lot of different reasons... Not the least because they need hardware and a bunch of installer resources so installers can actually install them. I'm checking if there is a way around that actually. I sent you a DM as well on this.  

On openness, I've spoken to a company which entire business is integrations with all kinds of manufacturers (batteries, EV chargers, and heat pump manufacturers). They are saying manufacturers are increasingly open, also in part because they are forced by EU regulation.