@sunandair ah, thank you. I had seen this numbers but didn't realise it was a cumulative (monthly) number. So yesterday I had COP of 2.64. current month...2.52. could be better I feel.
I had a look at temp sensors on flow/return pipes. Contacts look ok, but no insulation as Derek suggested should be present. Do I need to lag them with something?
Looking at the photo I suspect that the upper sensor is not making good thermal contact, particularly at the end section where the sensor is often located within the actual sensor body.
I would suggest getting some new cable ties, along with some thermally conductive paste, and good quality pipe insulation of the correct size.
Remove the old cable ties, and clean both the pipework and sensors, then apply thermally conductive paste and refit the sensors, with the cable tie near the end section.
Once the sensors have been correctly installed check the readings on the controller. When the readings have stabilsed cover the whole pipework with insulation and note if the readings change.
For info, found this guide for temp sensor best install. I might try moving the one that appears to be over some oxidation residue on my install.
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That's useful, thanks. I've located the sensors on mine; they look to be in good positions, have two cable ties, with pipe lagging over them. I can't see any evidence of thermal paste though. I notice Derek has mentioned paste in a follow up post - how important is this (marginal or..?). Adding some tin foil would be easy enough for me to test.
Generally I'd say things are running well, it's just I'm still to see a COP starting with a 3. Feels like something in the energy monitoring side isn't quite right.
For instance what bearing do these energy monitor settings have on accuracy (the water pump ones in particular), mine are all at the defaults..
n.b. the title of this thread is not aging well lol.
If you go to melcloud and click on reports tab then select energy usage.....set the start and end dates for period you want ...for a single day use both dates the same....it gives a pie chart showing total consumed and below that a bar chart for consumed and delivered...you can deselect the hot water by clicking on the orange bit under the bar charts if you want just heating consumption.
All said on my melcloud it does not show cop which I would have thought was very easy to do but as you said it's just delivered/ consumed.
As I understand it you have to have extra monitoring input to the FTC board (such as you would with one of the MMSP monitoring packages) to get more detailed information through MelCloud. I have a meter installed in the CU measuring the heat pump electrical use but no electric meter or heat meters connected to the FTC, and so in MelCloud only monthly usage totals are available to me. Adding an electric meter providing a pulsed reading output is probably not too complicated depending on location, I don't know whether this would automatically activate some of the extra MelCloud data.
I find the unit's own measurement of it's electric consumption to be too high. More inaccurate at lower power draws I think, so a greater proportional disparity in the warmer months. January's total was about 10% above the accurately measured consumption. That'll help your COP calculation!
Mitsubishi EcoDan 8.5 kW ASHP - radiators on a single loop 210l Mitsubishi solar tank Solar thermal 3.94kW of PV
I find the unit's own measurement of it's electric consumption to be too high. More inaccurate at lower power draws I think, so a greater proportional disparity in the warmer months. January's total was about 10% above the accurately measured consumption. That'll help your COP calculation!
That's exactly what I think I'm observing. 'Believeable' COP values in cold conditions (2.3-2.5), nothing over 3 in milder conditions.
For info, found this guide for temp sensor best install. I might try moving the one that appears to be over some oxidation residue on my install.
-- Attachment is not available --
That's useful, thanks. I've located the sensors on mine; they look to be in good positions, have two cable ties, with pipe lagging over them. I can't see any evidence of thermal paste though. I notice Derek has mentioned paste in a follow up post - how important is this (marginal or..?). Adding some tin foil would be easy enough for me to test.
Generally I'd say things are running well, it's just I'm still to see a COP starting with a 3. Feels like something in the energy monitoring side isn't quite right.
For instance what bearing do these energy monitor settings have on accuracy (the water pump ones in particular), mine are all at the defaults..
n.b. the title of this thread is not aging well lol.
I would have expected that the above should have been set by your installer, for example, if you have a 3kW immersion heater installed then the relevant value should have been set to read 3.
The pulse rate for the electricity meter input is only relevant if you have a meter connected to the controller.
Been lurking on this thread for a while and.......................... My DT is poor. Rarely more than a degree or two difference. I've tried changing the flow rate as per the previous video. The DHW and heating are set at #5 = 21LPM flow. I change it to 3 and............no change, 21LPM. So that isn't going to alter my DT.
I appear unable to set mode to AA. When I do as previously suggested there should be two temps shown on the controller screen. Target temp and actual current temp. I only get the single temp shown, the larger figure, so no AA. Help please because this system is costing more to run as I think it's capable of.
Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.
14 x 500w Monocrystalline solar panels.
I would have expected that the above should have been set by your installer
Yeah, I may query this with them. Although I also note from the manual 🙃 that Method 1 'should be used as a guide' so even getting the values set correctly may still provide inaccurate data. At least I now understand the limitations.
I appear unable to set mode to AA. When I do as previously suggested there should be two temps shown on the controller screen. Target temp and actual current temp. I only get the single temp shown, the larger figure, so no AA.
Mine does not show the smaller current temp number on the main controller either, but it's definitely running in AA mode. I had assumed that it was some quirk of having the remote wireless controller where the current temp is displayed.
Just an observation on the three charts you provided. I looks to me like your system was off between 12:38-14:16. Also, if you remove Tank Temperature and Set Tank Temperature from the graph you will get a better scale on the Flow Temperature and Return Temperature lines (makes it much easier to interpret).
I've tried changing the flow rate as per the previous video. The DHW and heating are set at #5 = 21LPM flow. I change it to 3 and............no change, 21LPM. So that isn't going to alter my DT.
I think we've now established that changing the Pump Speed via the controller may only be applicable with a pre installed setup. You may have to change the speed on your external pumps manually (on that note: I'm happy to play around with mine, but not confident advising others just yet).
Just an observation on the three charts you provided. I looks to me like your system was off between 12:38-14:16. Also, if you remove Tank Temperature and Set Tank Temperature from the graph you will get a better scale on the Flow Temperature and Return Temperature lines (makes it much easier to interpret).
It probably was mild enough not to require heating. Certainly not turned off.
Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.
14 x 500w Monocrystalline solar panels.
It probably was mild enough not to require heating. Certainly not turned off.
I think we're saying the same thing. Where there is a linear decrease in flow and return temps like that, that says to me that target temp has been hit and the HP and circulation pumps are off.
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