@derek-m I have two pumps in the same cupboard as the main gubbins and DHW cylinder but I have no idea how to change the anything on them. My DT is also barely 1/2c.
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.
@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.
You will probably need to change the speed of the water pump external to your heat pump to change the flow rate
@derekm and everyone else 😄
I said that I would investigate in more detail what is happening with my full mitsubishi packaged system pumps and have just emerged from the loft.
I was querying which pump was being controlled by the FTC controller....I have reduced the speed on mine to 1 in an attempt to increase DT from 5. The flow rate shows 11/12 litres fluctuations, if I alter speed to 5 the flow rate shown on the 540 enquiry increases as expected,,... Now!!
I got my good lady to increase the speed up and down while I sat beside the pumps but there was no evidence of either pump varying in speed.....this I cannot understand at all!!!.....So is the controller setting the pump speed and if so why does the 540 flow rate command show the increased flowrate
Also I mentioned some time back that I thought my DHW pump was constantly running when there was no call for heat.....this pump has manual speed control and I can confirm that the pump is running as it is evident when adjusting speed.....I don't understand that one either, if anyone has the preplumbed ecodan system just wondered if they have noticed similar behaviour.
One of the pumps is an Auto pump with led performance lights, I don't fully understand how this works as the manual shows a lot of technical variables--See attachment (not in correct order)-----this appears to be the heating circuit pump.
The other pump is on the heat pump return and has no manual adjustment so I would have thought this is the pump controlled by the FTC controller speed setting...but as stated earlier no evidence of speed change when setting varied.
@derek-m I have two pumps in the same cupboard as the main gubbins and DHW cylinder but I have no idea how to change the anything on them. My DT is also barely 1/2c.
Ok it’s not too surprising you’ve got a DT of 1/2c if your flow rate is in the 20s can you take a picture of the pumps? As an alternative perhaps you could just ask your installer to adjust them for you? At least you have a better understanding of what you should be getting....?
it sounds like you’ve got a pretty normal heating and hot water setup. One pump should switch off when the DHW cylinder is reheating.
@sunandair Picture of one of the pumps below. The other on the adjacent pipe is upside down of this. They both seem to operate at the same time when one of DHW or CH is required. The only difference I can tell is only one of the valves for either DHW or CH is open.
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.
it would appear you have a variable speed pump here is a video about it
So it should be quite simple to change the pump speed. There should be an illuminated number in the front panel when the pump is on and running. If you make a note of the number you can re set it back to that setting If you need to. To change the speed of the pump press the mode button several tomes until number 2 shows in the screen then do the same with the second pump. Then test the pump speed. Then refer back to the message about setting the DT... hope this helps
@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.
You will probably need to change the speed of the water pump external to your heat pump to change the flow rate
@derekm and everyone else 😄
I said that I would investigate in more detail what is happening with my full mitsubishi packaged system pumps and have just emerged from the loft.
I was querying which pump was being controlled by the FTC controller....I have reduced the speed on mine to 1 in an attempt to increase DT from 5. The flow rate shows 11/12 litres fluctuations, if I alter speed to 5 the flow rate shown on the 540 enquiry increases as expected,,... Now!!
I got my good lady to increase the speed up and down while I sat beside the pumps but there was no evidence of either pump varying in speed.....this I cannot understand at all!!!.....So is the controller setting the pump speed and if so why does the 540 flow rate command show the increased flowrate
Also I mentioned some time back that I thought my DHW pump was constantly running when there was no call for heat.....this pump has manual speed control and I can confirm that the pump is running as it is evident when adjusting speed.....I don't understand that one either, if anyone has the preplumbed ecodan system just wondered if they have noticed similar behaviour.
One of the pumps is an Auto pump with led performance lights, I don't fully understand how this works as the manual shows a lot of technical variables--See attachment (not in correct order)-----this appears to be the heating circuit pump.
The other pump is on the heat pump return and has no manual adjustment so I would have thought this is the pump controlled by the FTC controller speed setting...but as stated earlier no evidence of speed change when setting varied.
The plot thickens!
Hi Dave,
Can you provide close up photo's of the pumps so that they can be identified. Also the pump without any obvious manual control, how many cables are connected to it?
@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.
Heat pump switched off at 13:04, possibly immediately after a defrost cycle? Difficult to tell from only that one graph and no description of what you were expecting.
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