I see the same pattern when my HP is off and the water circulation pumps stay on. Essentially the flow and return water mix until they match temps, and of course the temp decreases as any remaining heat gets dumped in the room. Basically, all normal.
n.b. It looks like your pumps display the current wattage when running. Might be worth making a mental note of what wattage they are running at before you change modes. You'll get some sense of savings on the pumps running once you reduce the speed if that provides the desired outcome on DT.
@derek-m i see your point about the RFT not being up to temp shortly after a call for higher LFT which would result in a higher DT.
i delved further into the settings and indeed found these settings...
Booster Heater1 Capacity - which is set at 2kwh Booster Heater2 Capacity - which is set at 4kwh
just because these settings are there, does it mean my system has them? i suppose given that there are some values attached makes it a bit more likely.
i have googled ecodan booster heater but am none the wiser about where they might be in my system. do you have any foresight? would you suggest I knock these values back to 0kwh and observe what happens with flow temps?
some other readings I found...
flow temp range: min 30; max 55 ( I believe I am safe to reduce the min to 25. 25 is also my set min LFT temp on WC) room temp control: fast; 10m (only a concern for AA mode I believe) h/p thermo diff adjust: on. +5 / -5
I see the same pattern when my HP is off and the water circulation pumps stay on. Essentially the flow and return water mix until they match temps, and of course the temp decreases as any remaining heat gets dumped in the room. Basically, all normal.
n.b. It looks like your pumps display the current wattage when running. Might be worth making a mental note of what wattage they are running at before you change modes. You'll get some sense of savings on the pumps running once you reduce the speed if that provides the desired outcome on DT.
I know all are trying to help but this is all becoming disjointed, confusing and somewhat frustrating. My knowledge is minimal and my confidence is low to make changes to pumps etc when then told something about wattages and ....................is doing my head in a bit. Please don't take that as the comment of an ingrate. I really don't have the wherewithal to play like this and risk my warranty. Were I to call the installer back he will only tell me it is what it is and charge a large amount plus mileage (he isn't local) for the privilege.
Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.
14 x 500w Monocrystalline solar panels.
@morgan just checking with @derek-m for correct pump speed Constant or proportional options
have you seen the video of your pump? When your pump is running what light symbols do you have? This will tell us what speed it is running at.
how do you feel now about adjusting the pump speed based on my earlier instructions message.... then testing the adjusted thermistor readings. And flow rate...?
@derek-m ref: @morgan pump speed. would you suggest proportional pressure pump setting for this radiator installation presumably with thermostatic radiator valves?
I was going to suggest speed2 first and then try speed1 if speed is still too high.
It is difficult to say without knowing exactly what equipment is installed and how it is being used. Probably starting at a setting of 2 and then checking the flow rate and DeltaT is a good starting point.
I know all are trying to help but this is all becoming disjointed, confusing and somewhat frustrating.
I know: it would be much easier for me to follow if you and anyone else who isn't Jasper01 started your own new topics in the ASHP section about the problems with your system. I don't know if @editor Mars can split this topic up or if it's mixed-up too much.
@morgan just checking with @derek-m for correct pump speed Constant or proportional options
have you seen the video of your pump? When your pump is running what light symbols do you have? This will tell us what speed it is running at.
how do you feel now about adjusting the pump speed based on my earlier instructions message.... then testing the adjusted thermistor readings. And flow rate...?
re the light symbols, it's not easy to tell because the lights flash momentarily then there's just a single light to indicate the pump is running, no figure displayed. That's my recollection. I will need to force it to start up and take a full on look at it and let you know.
Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.
14 x 500w Monocrystalline solar panels.
@sunandair I've done a 540 enquiry (posted earlier). 21LPM at setting 5. The same at setting 3 so it appears that I cannot change the flow rate.
The rest of your post re flow and return thermistor readings and setting the AA parameters is beyond my current comprehension.
ok, but as you can already do the 540 enquiry means you are making really good progress.
Data - You’ve already been Data Gathering- on the menu screen where you selected running information you will see below it “Thermistor readings”... If you click on it you will see it gather all the main thermistor readings you have. The Flow and Return temperatures are in the bottom left corner labelled THW1(flow) and THW2(return) so write these numbers down and subtract the thw2 from thw1 The result should give you your DeltaT
Practical activity-
how many pumps do you have? Are you operating radiators only or is it Domestic Hot water also? Can you send a picture of the pumps? Their speed may only be controlled by physical push buttons on the pump itself.
Principal objective
Manually slow down pumps from 21lpm
do a 540 check (flow rate LPM)
check new thermistor readings (calc new DT)
Adjust pump speed again if needed
Target - achieve a DeltaT of 5 or 6 ltrs per minute with a flow rate within the operating limits of your heat pump (our 8.5kw Ecodan is 10.8 to 24 LPM)
If you can answer any of the questions first that would be a good place to start then we can look at the actions later.
ok I’ve looked at my own setup and we are on constant curve speed 1 pump setting
are you ready to look into your Delta T adjustment? It’s not a problem if you’d rather not. But the instructions I wrote are back on this post if you’re interested.
first step is to read what the existing pump speed is from the illuminated pump face.... should be something like C lll (meaning constant3) or another symbol like p lll etc.
second step I said to change the speed by repeatedly pressing the mode button until c l shows on the pump face, this means constant l (the slowest speed with constant pressure)
you will need to do this adjustment to C1 speed on both pumps before you check for flow speed.
are you ready to look into your Delta T adjustment? It’s not a problem if you’d rather not. But the instructions I wrote are back on this post if you’re interested.
Not yet. Trying to get pictures of the pump display atm re an earlier question.. Got it going but it all went too fast to get clear pictures of the sequence. Now the pump won't stop so I need to try again in a bit and video it switching on for clarity. I don't know how to sensibly move my input into a separate thread and start over.
Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.
14 x 500w Monocrystalline solar panels.
@derek-m i see your point about the RFT not being up to temp shortly after a call for higher LFT which would result in a higher DT.
i delved further into the settings and indeed found these settings...
Booster Heater1 Capacity - which is set at 2kwh Booster Heater2 Capacity - which is set at 4kwh
just because these settings are there, does it mean my system has them? i suppose given that there are some values attached makes it a bit more likely.
i have googled ecodan booster heater but am none the wiser about where they might be in my system. do you have any foresight? would you suggest I knock these values back to 0kwh and observe what happens with flow temps?
some other readings I found...
flow temp range: min 30; max 55 ( I believe I am safe to reduce the min to 25. 25 is also my set min LFT temp on WC) room temp control: fast; 10m (only a concern for AA mode I believe) h/p thermo diff adjust: on. +5 / -5
thank you all for continued advice & support
I am not certain if the fact that there is a value set, that this means that one or more booster heaters are actually installed. As far as I am aware they would normally be located within a suitable vessel on the flow line from the heat pump.
An easy way to check if the booster heaters are actually being used would be to check the position of DIP Switch SW1-5, which enables (On) or disables (Off) the booster heaters.
You can see the details in Table 5.1.1 in the attached manual on page C27.
I cannot foresee any problem in lowering the minimum flow temperature setting from 30 to 25.
I would suggest changing the room temperature control from fast to normal, and if you decide to use AA mode then start with a Time Interval of 60 minutes.
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