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Daikin Altherma 3

Maidenhead · Semi-detached · 113 m² · 1940 to 1982 · 8 kW · radiators · installed by Octopus Energy Services

Last 7 days

169 hourly rows · MID-class heat meter present: yes
4.28efficiency (COP) over 169 hours, from the heat meter
better than 90% of the metered fleet in January 2026
Electricity used
42 kWh
Heat delivered
180 kWh (heat meter)
Estimate without heat meter
flow sensor 4.32 · temperature model 4.36
Mean outdoor temperature
9.1 °C · 54 space-heating hours · cooling 0 kWh removed (0 kWh electricity), kept out of the COP
Flow temperature at 0 °C outside
34.2 °C (curve slope -0.40 per K)
Flow − return while heating
3.9 K
House needs at −3 °C
3.0 kW (unit rated 8 kW) · fit r² 0.01
Hot water
30% of electricity, COP 3.33
infoOnly 54 space-heating hours in this window
Space-heating findings need at least 60 hours with the compressor running below 15 °C outside. Choose a winter window or come back during the heating season.

Day by day

electricity per daydaily COP3.0 floor
electricity, kWh per day0472026-10-31: 0.2 kWh, outside 11.5 °C2026-11-01: 5.2 kWh, outside 8.6 °C2026-11-02: 5.1 kWh, outside 9.4 °C2026-11-03: 5.4 kWh, outside 9.3 °C2026-11-04: 7.4 kWh, outside 9.1 °C2026-11-05: 5.2 kWh, outside 9 °C2026-11-06: 6.8 kWh, outside 9 °C2026-11-07: 6.8 kWh, outside 4.7 °Cdaily COP (heat ÷ electricity)1352026-11-01: COP 4.022026-11-02: COP 4.072026-11-03: COP 4.142026-11-04: COP 4.672026-11-05: COP 4.212026-11-06: COP 4.632026-11-07: COP 4.110-3111-0111-0211-0311-0411-0511-0611-07
Daily COP needs a heat meter; days without one show electricity only.
Public system published by its owner on HeatpumpMonitor.org. Cycling (starts per hour) comes from the site’s 365-day statistic. Findings use installer rules of thumb; see methodology.