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Stiebel Eltron WPL Premium

York, North Yorkshire · Detached · 143 m² · 2012 or newer · 7 kW · radiators · installed by Clear Skies Energy Ltd

1–31 Dec 2025

745 hourly rows · MID-class heat meter present: yes
5.36efficiency (COP) over 745 hours, from the heat meter
better than 99% of the metered fleet in January 2026
Electricity used
230 kWh
Heat delivered
1232 kWh (heat meter)
Estimate without heat meter
flow sensor 5.17 · temperature model 4.38
Mean outdoor temperature
7.0 °C · 471 space-heating hours · cooling 1 kWh removed (1 kWh electricity), kept out of the COP
Flow temperature at 0 °C outside
31.6 °C (curve slope -0.22 per K)
Flow − return while heating
4.7 K
House needs at −3 °C
2.3 kW (unit rated 7 kW) · fit r² 0.00
Hot water
no hot-water flag in data
infoUnit is rated 7 kW but the house needs about 2.3 kW at −3 °C
Oversizing causes cycling in mild weather. Cannot be fixed cheaply now, but the curve and minimum run time can limit the damage.

Day by day

electricity per daydaily COP3.0 floor
electricity, kWh per day06122025-12-01: 5.8 kWh, outside 9.8 °C2025-12-02: 7.3 kWh, outside 7 °C2025-12-03: 10.2 kWh, outside 3.9 °C2025-12-04: 8.2 kWh, outside 6.1 °C2025-12-05: 9.8 kWh, outside 4.9 °C2025-12-06: 6.4 kWh, outside 8.8 °C2025-12-07: 5.4 kWh, outside 8.6 °C2025-12-08: 5.4 kWh, outside 9.5 °C2025-12-09: 3.7 kWh, outside 11.9 °C2025-12-10: 4.2 kWh, outside 10.2 °C2025-12-11: 4.9 kWh, outside 9 °C2025-12-12: 5.8 kWh, outside 8 °C2025-12-13: 9 kWh, outside 6.1 °C2025-12-14: 5.7 kWh, outside 10 °C2025-12-15: 4.3 kWh, outside 9.8 °C2025-12-16: 7.6 kWh, outside 5.5 °C2025-12-17: 9.4 kWh, outside 5.6 °C2025-12-18: 5.3 kWh, outside 9.2 °C2025-12-19: 7.1 kWh, outside 7.4 °C2025-12-20: 9.1 kWh, outside 4.5 °C2025-12-21: 7.2 kWh, outside 8 °C2025-12-22: 4.9 kWh, outside 8.5 °C2025-12-23: 6.5 kWh, outside 7.1 °C2025-12-24: 8 kWh, outside 5.7 °C2025-12-25: 10.2 kWh, outside 5 °C2025-12-26: 10.4 kWh, outside 3.4 °C2025-12-27: 10.7 kWh, outside 4.6 °C2025-12-28: 8.8 kWh, outside 6.4 °C2025-12-29: 8 kWh, outside 5.4 °C2025-12-30: 11.7 kWh, outside 3.8 °C2025-12-31: 10.1 kWh, outside 1.8 °C2026-01-01: 0.1 kWh, outside 4.8 °Cdaily COP (heat ÷ electricity)1352025-12-01: COP 5.882025-12-02: COP 5.342025-12-03: COP 4.942025-12-04: COP 5.352025-12-05: COP 52025-12-06: COP 5.872025-12-07: COP 5.742025-12-08: COP 5.742025-12-09: COP 6.092025-12-10: COP 6.122025-12-11: COP 5.842025-12-12: COP 5.92025-12-13: COP 5.12025-12-14: COP 5.72025-12-15: COP 6.472025-12-16: COP 5.322025-12-17: COP 5.142025-12-18: COP 6.172025-12-19: COP 5.552025-12-20: COP 5.292025-12-21: COP 5.632025-12-22: COP 5.972025-12-23: COP 5.672025-12-24: COP 5.352025-12-25: COP 5.012025-12-26: COP 4.772025-12-27: COP 4.792025-12-28: COP 5.212025-12-29: COP 5.32025-12-30: COP 4.772025-12-31: COP 4.2912-0112-0512-0912-1312-1712-2112-2512-29
Daily COP needs a heat meter; days without one show electricity only.

The installed heating curve

one heating hourfitted curve50 °C
2030405060-4-12581114outdoor temperature, °Cflow temperature, °C
Each point is one hour of space heating. Lower and flatter is cheaper; well-set radiator systems sit around 35–42 °C at 0 °C outside.
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.