Do you think the forum member comments are factual? Because I spoke to a tech advisor back in April who stated the AA system does make reference to the weather compensation curve. Could it be we are just fed whatever sounds plausible.
Whats your system doing? How are things operating for you?
ps I couldn’t translate any other docs but I’ll try again when I’m on my laptop.
I can only say that one comment regarding the AA not needing the WC curve to be set, stems from this mitsubishi document that I've shared(photo as well).
It looks like in general, in the HP world the old documents shared more info in the past than the present ones.
I don't have a system yet.
I've translated in google the doc.
P.S. I assume the best way to find out is to set the WC very high/low and see what AA does.
Hope you don't mind me joining this topic as well.
Here's a chart with the AA 'thermo diff adjust' option turned OFF, OAT was mild (13C). The way I have interpreted this is that it's apparent the Ecodan wants to maintain a LWT/RWT delta of 5. By turning off the thermo diff adjust option we're not limiting the target LWT, it looks like it will keep going until it finds that equilibrium itself (in this case it got to near 50C LWT before it thought it could back off and run steady state). On the plus side, there is no cycling. On the minus side, it's no good for comfort levels (or cost?), and the overshoot in IAT is some 1.5 degrees.
In terms of the thermo diff adjust options (when ON of course) I annotated on this chart last winter. I also added the compressor frequency at 5 min intervals along the bottom of the chart - note the frequency ramps up at the end of the cycle. On the subject of frequency I wonder what the max is - I see from the service manual the range is 0-255, but I've seen a few references online that most ASHP's have a maximum in the 100 range (which seems plausible as the 36-56 numbers I recorded would have the compressor running at 30-50% capacity). Anyone know what the max frequency an Ecodan can run at for sure?
In terms of the thermo diff adjust options (when ON of course) I annotated on this chart last winter. I also added the compressor frequency at 5 min intervals along the bottom of the chart - note the frequency ramps up at the end of the cycle. On the subject of frequency I wonder what the max is - I see from the service manual the range is 0-255, but I've seen a few references online that most ASHP's have a maximum in the 100 range (which seems plausible as the 36-56 numbers I recorded would have the compressor running at 30-50% capacity). Anyone know what the max frequency an Ecodan can run at for sure?
Interesting. Is this running in AA or wC? How do you know the target flow temp is 37? Wondering if- Does thermo diff affect WC or fixed flow temp eg on/ off operations?
Interesting. Is this running in AA or wC? How do you know the target flow temp is 37? Wondering if- Does thermo diff affect WC or fixed flow temp eg on/ off operations?
That's in AA mode. General consensus (until now?) was that AA mode used the WC curve as a baseline and adapted from there - 37C was spot on where my curve was set versus OAT etc. It also sat perfectly within the +3 (overshoot) -7 (undershoot) settings I'd set in the thermo diff adjust options.
Those +- options are only available in room temp (AA) mode.
So Auto Adapt is intended to deal with localised internal temperature changes eg solar gain when curtains are opened, room increase from cooking or increased occupation etc.
It tries to do this via monitored history, prediction and anticipation. And should Adapt accordingly.
It appears to refer to outside temp changes and the existing compensation curve and makes additional ‘learned’ changes.
The suggestion appears to be a saving in energy over the compensation curve rather than an overrunning of its flow temperatures.
Is this what people are actually seeing. Can adjustments be made to thermo diff settings and interval monitoring to modify the over running of set temperatures?
And as if that’s not enough, Does short cycling due to low output interfere with interpretation of what’s happening during room heating process?
So Auto Adapt is intended to deal with localised internal temperature changes eg solar gain when curtains are opened, room increase from cooking or increased occupation etc.
It tries to do this via monitored history, prediction and anticipation. And should Adapt accordingly.
It appears to refer to outside temp changes and the existing compensation curve and makes additional ‘learned’ changes.
The suggestion appears to be a saving in energy over the compensation curve rather than an overrunning of its flow temperatures.
Is this what people are actually seeing. Can adjustments be made to thermo diff settings and interval monitoring to modify the over running of set temperatures?
And as if that’s not enough, Does short cycling due to low output interfere with interpretation of what’s happening during room heating process?
I don't know but I'd like to. I may try some experiments as it's easy for me to view the results using the monitoring data. If anyone wants to suggest some scenarios (within reason) I'll give it a go. The first one I was going to do was to switch thermo diff off and see what happens compared to having it on.
You could try different settings for the thermo diff., say +1C and -1C, then +2C and -2C etc. At each setting raise the desired room temperature by 0.5C or 1C and monitor how long the system takes to increase the room temperature. Then set the desired temperature back to its original setting to see how long its takes to cool back down.
The tests should then give some idea of the thermal mass of your home as well as how different thermo diff. settings affect the response of the system.
So Auto Adapt is intended to deal with localised internal temperature changes eg solar gain when curtains are opened, room increase from cooking or increased occupation etc.
It tries to do this via monitored history, prediction and anticipation. And should Adapt accordingly.
It appears to refer to outside temp changes and the existing compensation curve and makes additional ‘learned’ changes.
The suggestion appears to be a saving in energy over the compensation curve rather than an overrunning of its flow temperatures.
Is this what people are actually seeing. Can adjustments be made to thermo diff settings and interval monitoring to modify the over running of set temperatures?
And as if that’s not enough, Does short cycling due to low output interfere with interpretation of what’s happening during room heating process?
Keeping room temperatures reasonably constant is much easier said than done. It is probably like driving a car, which has extremely slow response, such that to increase speed from 50 mph to 60 mph would require the following. Press foot down on accelerator pedal, but nothing happens for 30 minutes, after which time the car starts to increase speed at a rate of 1 mph every 6 minutes, so after 1 hour and 30 minutes the goal of achieving a speed of 60 mph is accomplished. Just to complicate matters the car continues increasing its speed at a rate of 1 mph every 6 minutes for an additional 30 minutes after you have remove your foot from the pedal. 🙄
This is the type of problem with which a heat pump controller would need to deal with in AA mode.
As shown in the colourful 'Two Controls simulation on a day', much of the heavy lifting appears to be done by the WC curve, which is one of the reasons why it should be correctly optimised before AA mode is selected.
I believe that one of the major factors that could affect the response of a system in AA mode, is the thermal mass of the home. A home with a small thermal mass will respond much quicker than one with a large thermal mass, like a sports car compared to a heavily loaded truck.
I would hope that adaptation part of AA is to modify the system response to match that of the home, though this may take some time to accomplish. The other factors to consider is that even if the controller has adjusted to the thermal mass, things like solar gain, wind chill, rain effect and human activity are not constant, but can vary from day to day or even hour to hour.
A combination of all the above factors may therefore determine how far the actual room temperature deviates from the desired value.
If my understanding is correct, then reducing the thermo diff. settings (certainly the + one), should help reduce overshoot by the LWT, though it may introduce cycling, particularly in milder weather conditions. Conversely it could just be a matter of allowing the AA to adapt to the response times of your particular system. Though it should be remembered that the response times will vary with the weather conditions, during milder conditions your home will heat up quicker and cool down slower, and vice versa during colder weather conditions.
I hope that this helps but please feel free to question further.
I had a bit of time on my hands this afternoon (and it was raining) so decided to have a quick 'play' with AA mode again. OAT was 12C, and I set my WC curve to 38C at both ends (i.e. it was flat) to see if AA mode made any use of it. Themo diff adjust is back ON again, with a +3 / -5 configuration. I painstakingly noted the compressor frequency at 5 min intervals, and have added them to the timeline at the bottom of the graphs.
It seems that the target temp it has chosen is 32C (so not been influenced by the WC curve by the look of it!?). The first cycle LWT maxed out at around 35C (seems to have hit the +3 nicely) then reduced to 27C (seems to have hit the -5 nicely). The other two cycles are a little less obvious (there appears to be no attempt at the +3). Our DWH comes on at 15:00 so interrupted things, IAT had come up 0.5C in the two hours the heating was running though.
Comfort levels were very good. If I'm correct(?) in that the Ecodan compressor runs in a frequency range between 0-100Hz, the compressor numbers are sitting at the lower end (seems to like 36Hz, one peak at 46Hz when chasing the +3).
I had a bit of time on my hands this afternoon (and it was raining) so decided to have a quick 'play' with AA mode again. OAT was 12C, and I set my WC curve to 38C at both ends (i.e. it was flat) to see if AA mode made any use of it. Themo diff adjust is back ON again, with a +3 / -5 configuration. I painstakingly noted the compressor frequency at 5 min intervals, and have added them to the timeline at the bottom of the graphs.
It seems that the target temp it has chosen is 32C (so not been influenced by the WC curve by the look of it!?). The first cycle LWT maxed out at around 35C (seems to have hit the +3 nicely) then reduced to 27C (seems to have hit the -5 nicely). The other two cycles are a little less obvious (there appears to be no attempt at the +3). Our DWH comes on at 15:00 so interrupted things, IAT had come up 0.5C in the two hours the heating was running though.
Comfort levels were very good. If I'm correct(?) in that the Ecodan compressor runs in a frequency range between 0-100Hz, the compressor numbers are sitting at the lower end (seems to like 36Hz, one peak at 46Hz when chasing the +3).
That's quite interesting. It makes me wonder if AA has stored a copy of the original WC curve, which it may be adapting over time. What were the settings of your WC curve before you made the changes?
I still feel that AA mode will make reference to variations in OAT, since without it I suspect just a room sensor would fail to control the temperature, without excessive overshooting and undershooting.
Using my Ecodan simulation tool, it shows that the 7C change in OAT from 14C to 7C today, would require the LWT to be increased from 32.39C to 40.19C in a matter of 10 hours or so, which would require a 192% increase in electrical energy.
