Our COP for September

is reported at 7.6 which I'm taking with a pinch of salt because I think a COP of 7.6 is exceptional. I'd like to think it's true but the Mitsubishi system's figures don't seem to have a reputation for total accuracy.


Mitsubishi COP graph for September 2026. 46.9kWH of energy consumed, 353.9kWh of energy produced and a COP of 7.6


The export says 46.9kWh of energy was consumed and 353.9kWh of energy was produced (well, pumped) which would make the COP 7.5 which seems very high.

I'm expecting a good COP as we have a well insulated new build with full underfloor heating enabling us to run a low flow temperature.

Looking at HeatpumpMonitor.org I see there's a 8kW Mitsubishi system in Gloucestershire that's got a heating COP for September of 6.1 and a hot water COP of 3.8. The total COP is 4.9 due to the balance of energy use across heating and hot water.



Perhaps our figures are not too far of the mark.

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