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Hi @kev-m our installer, Ecobubl did a hear loss and heat demand calc (required by MCS). He then used the Daikin ASHP tool to plug the data into, to come out with a heat demand and electric usage curve per month across the year. So I am just comparing my metered ASHP usage to this. I don’t know how much is supplied by my solar PV.
My solar PV does provide all of the hot water over the summer months. Meaning ASHP does run.
Daikin Altherma 3H HT 12kWh ASHP with Mixergy h/w cylinder; 4kW solar PV with Solic 200 electric diverter; Honda e and Volvo EX30 Ultra Twin Performance electric vehicles with Myenergi Zappi mk1 & Ohme chargers
@jeff yes both. Coming to about 21k kWh per year for both
Daikin Altherma 3H HT 12kWh ASHP with Mixergy h/w cylinder; 4kW solar PV with Solic 200 electric diverter; Honda e and Volvo EX30 Ultra Twin Performance electric vehicles with Myenergi Zappi mk1 & Ohme chargers
@julianc the ASHP used 560kw in October, last year on gas we used 3,000kw. So all together not too shabby in terms of use. I get that as a cop of 5.3 (if demand was broadly the same) however I've been running the house overnight at 20 and at 22° between 00.30 and 04.30 due to the go tariff. So the house is probably far warmer than last year.
@batalto, that's brilliant. Great to hear it's been such a success.
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@derek-m not sure I've been listening lol. My minimum temperature is set to 37° and the house is much more comfortable than it was with the water temperatures in the 20s. That said the radiators in our main room are far colder, so I think they need balancing.
As a note, I've never seen the ASHP use more than 3kw at any point yet. It's a 12kw pump, so it's performing admirably as far as I can see.
From the data I have October should be roughly 6% of your annual demand. 565/6% = 9,416kw for the year. Last year we used 34,683kw. So if we can get by with 9.4MW I get an annual COP of 3.68
@batalto 37 Deg C is vey high at this time of the year, I would expect to be running at least 10 Deg lower than that, however, it you have buffer tanks, system seperation, TRV's and thermostats, that is why you have to keep it that high with a resulting reduction in performance and increased electricity bill.
@heacol less than that just doesn't warm up our main room - which is where we have the most heat loss. There is no way to fix it without changing a huge area of glass; the bi folds are more than 12m2. I think there is also an issue with radiator balance as they are coldest in the house. Once that's fixed I might be able to lower the temperature. However my current price per KW is 10p averaged, so I'm doing pretty well.
@heacol the whole house, however that room would seem to have it's own climate. You can feel a difference in the doorway. The thermostat lives in the main room
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