Home / system #1381
Vaillant Arotherm+
Rhigos, Rhondda Cynon Taf · Bungalow · 190 m² · 2012 or newer · 5 kW · underfloor · installed by Net Zero Heating Solutions
Last 7 days
169 hourly rows · MID-class heat meter present: yes
4.44efficiency (COP) over 169 hours, from the heat meter
better than 92% of the metered fleet in January 2026
better than 92% of the metered fleet in January 2026
- Electricity used
- 95 kWh
- Heat delivered
- 420 kWh (heat meter)
- Estimate without heat meter
- flow sensor 4.48 · temperature model 4.25
- Mean outdoor temperature
- 8.1 °C · 117 space-heating hours · cooling 1 kWh removed (0 kWh electricity), kept out of the COP
- Flow temperature at 0 °C outside
- 36.5 °C (curve slope -0.86 per K)
- Flow − return while heating
- 2.9 K
- House needs at −3 °C
- 6.5 kW (unit rated 5 kW) · fit r² 0.10
- Hot water
- 23% of electricity, COP 3.63
warningOnly 2.9 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.
warningUnit is rated 5 kW but the house needs about 6.5 kW at −3 °C
Expect backup heater use on the coldest days. Improve insulation or draught-proofing before adding capacity.
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.