@derek-m super good news. I set the target temperature on my Honeywell "controller" to 25°C, then went out for the afternoon. Happily, the Ecodan seems to have completely ignored it. The temperature reading doesn't appear to have budged from 21°C - the radiators still seem normal, ie pretty much cool to the touch, & the house isn't sub-tropical. I will check the real-world Smart Meter readings at my usual times & see if anything was different, but fingers crossed

Posted by: @justinsb

@derek-m super good news. I set the target temperature on my Honeywell "controller" to 25°C, then went out for the afternoon. Happily, the Ecodan seems to have completely ignored it. The temperature reading doesn't appear to have budged from 21°C - the radiators still seem normal, ie pretty much cool to the touch, & the house isn't sub-tropical. I will check the real-world Smart Meter readings at my usual times & see if anything was different, but fingers crossed

Justin,

That is very promising news, of course the acid test will come when we start getting really cold weather. When a system is using only weather compensation, without any reference to the actual indoor temperature, matching the slope of the curve becomes more important.

Earlier today I posted a method of calculating what changes could be made to obtain the correct slope for the weather compensation, should it be deemed necessary, but at the moment I would suggest that you make no further changes to your system. Please monitor the operation of your system and post the results for others to envy.

@derek-m My system currently has the basic, stock Ecodan monitoring built in. Alas, I don't have the MMSP setup, as they wanted to charge me an extra £1000 + VAT for it (OK, which I would have got back over 7 years with the RHI, but it was an extra grand now, which I didn't feel like paying). It turns out that the stock monitoring system is called the EMP1 - The Energy Monitoring Pack 1 & it "estimates" your energy consumption to the nearest Kwh. The EMP2 (The Energy Monitoring Pack 2) will cost me around £150 + VAT & consists of two meters that measure electricity consumption down to each single Watt Hour (Wh). The EMP3 (The Energy Monitoring Pack 3) measures down to each single Wh for both electrical usage and heat produced, & is what you need to get your MMSP repayment on your RHI. The electrician is installing my EMP2 on Thursday, so my usage "should" be a little clearer (hopefully). The moral of that story is that you really, really, really want to have the MMSP package fitted to whatever ASHP you own, so don't let the salespeople talk you out of it so their bottom line price looks more competitive on paper.

I will keep on monitoring everything & report my findings back here

Plus, it will give me a baseline to see how adding 3.84Kw of Solar panels into the mix changes things, as that also goes live on Thursday or Friday.

TBH, I'm rather hoping that it will reduce my daily electricity consumption, even though it's Winter. As I mentioned earlier, daily Smart Meter readings show that my consumption is now 38Kwh per day, & pre-ASHP it was 13Kwh per day, so my 14Kw Ecodan has a daily electrical consumption of ~25Kwh to run 14 radiators & the hot water for the house. All credit for the electricity figures naturally goes to @derek-m for his guidance on the weather compensation settings 👍 

@justinsb 

Hi Justin,

I think that like you, most people would have baulked at the thought of paying over a grand for equipment that they thought would be of limited use, after-all, they just install an ASHP and it works perfectly, so why would you need to monitor it. Sorry, I'm being facetious again.

I have not researched the MMSP packages in detail, since I have an A2A ASHP, so MMSP would have been of little use. My understanding is the package 3 that you mention, consists of two temperature sensors, to measure the water flow a return temperatures, along with a flowmeter to measure how much water is flowing through the ASHP. The three signals are fed into a heat energy meter which calculates the heat energy produced by the heat pump. Of course you also require at least one electricity meter to quantify the amount of electrical energy used by the ASHP and maybe auxiliary equipment.

Without looking at the individual items of equipment it would be difficult to give actual costs, but a DIY installation would undoubtedly be several hundred pounds.

@derek-m The electrician who is coming is very nice, & has proved to be more than helpful when it comes to answering my questions. I'm going to quiz him on exactly what the EMP2 is, where it goes, & how it jacks into the system (& find about how an EMP3 would jack in too, if I can).

I'm always worried by financial quotes that involve large, round figures. Try running a claim for exactly £1000 past accounting & they'll usually laugh you out of the building, right before they reject the claim.

@justinsb,

EMP3 is what I have and yup it did cost over a grand (well it will when I pay for it).  It's not working yet hence why I haven't.  The bit that makes it expensive is the heat meter, which records energy produced.  I have it fitted but it's not recording data yet.  I'm trying to get the supplier back.

I'd be very interested in how your solar works alongside the ASHP so please keep us updated,

@kev-m @derek-m I'm just getting my figures to respond to your ASHP thread to the question of curves, flow temps & outside temperatures.

@justinsb 

Plus, it will give me a baseline to see how adding 3.84Kw of Solar panels into the mix changes things, as that also goes live on Thursday or Friday.

Today, our 4kW solar PV system generated a total of 4.31kWh, of which 1.6kWh was used to heat water in the hot water tank, the remainder was used within our home or to drive our A2A ASHP. No power was exported back to the grid.

You should certainly find that, Spring through to Autumn, a solar PV system is highly beneficial, it is less so in the Winter of course, but on a cold sunny day will help to power your heat pump.

@derek-m as they say, "Every little helps" 😀 

Speaking of which, my COP just hit 5.1 - Thank you

Posted by: @justinsb

@derek-m as they say, "Every little helps" 😀 

Speaking of which, my COP just hit 5.1 - Thank you

Unfortunately, the COP value is unlikely to stay that high as we go into the Winter months, though hopefully it will not fall too much.

You should also thank Brendon, for his perseverance at convincing many about the delights of weather compensation. Whilst we may not see eye to eye on other matters, he certainly knows a thing or two about waether compensation.

If you wish to increase your COP value a little higher, buy she who must be obeyed a jumper or two (for Christmas, so no extra cost), and turn the temperature down a degree.

Posted by: @derek-m

Mark,

I suspect that there is an error in the software for the display. The graph actually displays the true settings for Justin's system, water flow temperature of 45C @ ambient air temperature of 0C for the left hand end of the graph and water flow temperature of 20C @ ambient air temperature of 20C at the right hand end of the graph.

The 45C value displayed above the graph would appear to be correct, but the -30C to the right of the graph is obviously wrong.

Maybe you should point this out to Mr. Mitsubishi!!!!!!

@justinsb, @kev-m

I've just realised what is happening here. This display is showing you what the flow temp will be at any given outside temp.

So let's say you want to know what the flow temp will be when the outside temp is 13ºC you use the F4 button to move the X axis dot to 13ºC. The corresponding flow temp number will change as you move along.

So for me, at 13ºC outside temp will currently set a flow temp of 28ºC.

The reason it says -30ºC is because the chart defaults to the left side of the x axis.

@markc 

thanks, that makes sense.