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Grant Aerona HP290

Penrith, Cumbria · Detached · 85 m² · 1983 to 2011 · 6.5 kW · radiators · installed by IMS Heat Pumps

Last 7 days

169 hourly rows · MID-class heat meter present: yes
3.03efficiency (COP) over 169 hours, from the heat meter
better than 8% of the metered fleet in January 2026
Electricity used
117 kWh
Heat delivered
356 kWh (heat meter)
Estimate without heat meter
flow sensor 3.03 · temperature model 4.21
Mean outdoor temperature
7.8 °C · 125 space-heating hours
Flow temperature at 0 °C outside
33.5 °C (curve slope -0.29 per K)
Flow − return while heating
2.6 K
House needs at −3 °C
2.9 kW (unit rated 6.5 kW) · fit r² 0.13
Hot water
30% of electricity, COP 2.63
warningOnly 2.6 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.
infoUnit is rated 6.5 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.
valueReaching the fleet’s January median (3.69) would have saved about £5 in this window at 0.25 GBP/kWh. An estimate, not a promise.

Day by day

electricity per daydaily COP3.0 floor
electricity, kWh per day010202026-10-31: 5.4 kWh, outside 9.9 °C2026-11-01: 15.1 kWh, outside 8.5 °C2026-11-02: 20.1 kWh, outside 4.5 °C2026-11-03: 19.4 kWh, outside 7.6 °C2026-11-04: 16.5 kWh, outside 7.7 °C2026-11-05: 15.5 kWh, outside 9.3 °C2026-11-06: 17.5 kWh, outside 8.2 °C2026-11-07: 7.7 kWh, outside 7.7 °Cdaily COP (heat ÷ electricity)1352026-10-31: COP 3.032026-11-01: COP 3.122026-11-02: COP 2.722026-11-03: COP 3.082026-11-04: COP 3.092026-11-05: COP 3.12026-11-06: COP 3.082026-11-07: COP 3.1810-3111-0111-0211-0311-0411-0511-0611-07
Daily COP needs a heat meter; days without one show electricity only.

The installed heating curve

one heating hourfitted curve50 °C
2030405060-1135791113outdoor 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.