Heatproof
Deutsch
Sprache
DeutschEnglish
Darstellung
DunkelHellSystem
Ansicht
Einfach: nur der Rechnungs-CheckVollständig: alle Seiten
Home / system #620

Vaillant Arotherm+

Oxford, Oxfordshire · Semi-detached · 100 m² · 1900 to 1939 · 5 kW · radiators · installed by Boxt

Last 30 daysLast 7 days5 Jan – 4 Feb 2026 (winter reference)1–31 Dec 2025

5 Jan – 4 Feb 2026 (winter reference)

719 hourly rows · MID-class heat meter present: yes
3.75efficiency (COP) over 719 hours, from the heat meter
better than 59% of the metered fleet in January 2026
Electricity used
360 kWh
Heat delivered
1350 kWh (heat meter)
Estimate without heat meter
flow sensor 3.61 · temperature model 3.64
Mean outdoor temperature
5.0 °C · 630 space-heating hours
Flow temperature at 0 °C outside
36.0 °C (curve slope -0.60 per K)
Flow − return while heating
1.9 K
House needs at −3 °C
2.9 kW (unit rated 5 kW) · fit r² 0.55
Hot water
18% of electricity, COP 3.31
warningOnly 1.9 K between flow and return
Circulation pump may be set too high or emitters are undersized for the low flow temperature. Ask the installer to check pump speed.
noteOwner’s note on the source site: “Not recording negative heat on heat meter”

Day by day

electricity per daydaily COP3.0 floor
electricity, kWh per day011212026-01-05: 21.4 kWh, outside -2.1 °C2026-01-06: 21.3 kWh, outside -0.7 °C2026-01-07: 16.3 kWh, outside 2.9 °C2026-01-08: 13.9 kWh, outside 2.7 °C2026-01-09: 16.7 kWh, outside 2.6 °C2026-01-10: 20.6 kWh, outside -0.2 °C2026-01-11: 14.5 kWh, outside 4.2 °C2026-01-12: 8.5 kWh, outside 9.5 °C2026-01-13: 8.7 kWh, outside 7.8 °C2026-01-14: 14.5 kWh, outside 1.9 °C2026-01-15: 9.4 kWh, outside 6.7 °C2026-01-16: 10.9 kWh, outside 4.7 °C2026-01-17: 9.6 kWh, outside 6.4 °C2026-01-18: 9 kWh, outside 6.5 °C2026-01-19: 7.9 kWh, outside 8.1 °C2026-01-20: 8.7 kWh, outside 7.7 °C2026-01-21: 9.4 kWh, outside 6.8 °C2026-01-22: 7.9 kWh, outside 8 °C2026-01-23: 10.1 kWh, outside 6.5 °C2026-01-24: 10.3 kWh, outside 6.8 °C2026-01-25: 10.3 kWh, outside 6.1 °C2026-01-26: 11.8 kWh, outside 4.3 °C2026-01-27: 10.5 kWh, outside 6.5 °C2026-01-28: 12 kWh, outside 3.6 °C2026-01-29: 12.8 kWh, outside 3.5 °C2026-01-30: 10 kWh, outside 6.5 °C2026-01-31: 10 kWh, outside 6.5 °C2026-02-01: 9.4 kWh, outside 6.3 °C2026-02-02: 9.5 kWh, outside 6.4 °C2026-02-03: 13.3 kWh, outside 3.5 °C2026-02-04: 0.9 kWh, outside 1.5 °Cdaily COP (heat ÷ electricity)1352026-01-05: COP 2.972026-01-06: COP 3.012026-01-07: COP 3.532026-01-08: COP 3.632026-01-09: COP 3.452026-01-10: COP 32026-01-11: COP 3.562026-01-12: COP 4.492026-01-13: COP 4.242026-01-14: COP 3.372026-01-15: COP 4.112026-01-16: COP 3.912026-01-17: COP 4.12026-01-18: COP 4.142026-01-19: COP 4.262026-01-20: COP 4.162026-01-21: COP 4.12026-01-22: COP 4.262026-01-23: COP 4.072026-01-24: COP 4.112026-01-25: COP 4.092026-01-26: COP 3.942026-01-27: COP 4.192026-01-28: COP 3.862026-01-29: COP 3.792026-01-30: COP 4.082026-01-31: COP 4.062026-02-01: COP 4.12026-02-02: COP 4.052026-02-03: COP 3.672026-02-04: COP 2.801-0501-0901-1301-1701-2101-2501-2902-02
Daily COP needs a heat meter; days without one show electricity only.

The installed heating curve

one heating hourfitted curve50 °C
2030405060-8-5-21471013outdoor 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.