Home / system #267
Stiebel Eltron WPE-I 12 HK Premium
Shetland · Detached · 319 m² · 2012 or newer · 12 kW · underfloor · installed by A J Pottinger
Last 7 days
144 hourly rows · MID-class heat meter present: yes
4.25efficiency (COP) over 144 hours, from the heat meter
better than 90% of the metered fleet in January 2026
better than 90% of the metered fleet in January 2026
- Electricity used
- 124 kWh
- Heat delivered
- 525 kWh (heat meter)
- Estimate without heat meter
- flow sensor 2.92 · temperature model 4.13
- Mean outdoor temperature
- 8.9 °C · 80 space-heating hours
- Flow temperature at 0 °C outside
- 42.6 °C (curve slope -0.47 per K)
- Flow − return while heating
- 6.0 K
- House needs at −3 °C
- 2.9 kW (unit rated 12 kW) · fit r² 0.00
- Hot water
- 55% of electricity, COP 3.37
warningHot water uses 55% of electricity at COP 3.37
Lower the tank target to 45–48 °C, heat water once a day in the warmest hours, and disable weekly legionella cycles unless required.
infoUnit is rated 12 kW but the house needs about 2.9 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.
noteOwner’s note on the source site: “0W standby power review required”
Day by day
electricity per daydaily COP3.0 floor
The installed heating curve
one heating hourfitted curve50 °C
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.