Real world COP vs. manufacturer claim
The purpose of this poll is determine whether your real world, month-on-month, heat pump SCOP comes close to the manufacturer’s claims.
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Our lifetime COP is 2.7 and the published COP of our 18kW Global Energy Systems heat pump is supposed to be 3.46 at 45C flow temperature.
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I'm trying to work out the best xxxgate name for this, as in dieselgate. A catchy name will do wonders for publicising the problem. COPgate may be the obvious ones, but to me it sounds like something is wrong with the police, which is probably true, but that's another story. Flowgate was another candidate, but to me it misses the mark. For a moment I considered FreedomGate but that unfairly picks them out. I open the floor to any other suggestions.
Midea 14kW (for now...) ASHP heating both building and DHW
Posted by: @cathoderayI'm trying to work out the best xxxgate name for this, as in dieselgate. A catchy name will do wonders for publicising the problem. COPgate may be the obvious ones, but to me it sounds like something is wrong with the police, which is probably true, but that's another story. Flowgate was another candidate, but to me it misses the mark. For a moment I considered FreedomGate but that unfairly picks them out. I open the floor to any other suggestions.
Air-to-Watergate?
Posted by: @oswiuAir-to-Watergate?
Very good, I think that will be a hard one to beat!
Midea 14kW (for now...) ASHP heating both building and DHW
@oswiul that’s very good. I may have to steal that as a headline for my next post that I’m working in.
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Not the easiest poll to answer since Mitsubishi publish multiple figures at different scenarios.
Perhaps more telling, though, is what the heat pump’s performance has been compared with what our installers gave as a ballpark figure; they said 3 - 3.5 and we’ve achieved 3.22. By any reasonable yardstick, I’d say we received a valid and accurate estimate and I’m happy with that.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; suus solum profundum variat"
Did you need to make any changes to how your heat pump was initially configured to achieve that figure?

Nope. It’s running exactly as the installers left it, apart from putting it in holiday mode for a couple of weeks for the obvious reasons.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; suus solum profundum variat"
You must have been lucky, and found a real Heating Engineer.

I was, @derek-m, and I’ve been recommending them ever since. I was particularly impressed when our next door neighbours invited them round to give a quote and they advised that the neighbours’ money would be better spent on insulation than a new heating system. Clearly not in it for a fast buck.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; suus solum profundum variat"

In addition, @derek-m, that real world COP is being delivered by my (apparently very average - according to one expert) Mitsubishi unit. To me, that goes to show just how unimportant the choice of manufacturer is compared to the overall system being designed correctly. But then you knew that already and have been banging that drum since before I joined here, wouldn’t you say?
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; suus solum profundum variat"
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