Octopus Cosy 6 Air Source Heat Pump
Octopus's 6kW air source heat pump for typical 1–4 bed UK homes (heat loss <5.6kW). R290 refrigerant, 8-year warranty, ~£4,460 fitted after BUS grant.
4.3 / 5
★★★★★ ★★★★★ Highly recommended
Strengths
- All-in installed cost typically £4,460 after the £7,500 Boiler Upgrade Scheme grant - among the most price-transparent UK heat pump packages
- R290 natural refrigerant (GWP of 3) - future-proof against the F-gas regulation tightening that will hit R32-based competitors
- Generous warranty: 8-year product cover plus 5-year labour, both backed by Octopus directly rather than a third-party installer
Watch outs
- SCOP 3.4 at 50°C flow / 2.8 at 65°C flow - mid-range efficiency; older homes that can't run at low flow temperatures will see noticeably higher running costs than published headline figures imply
- Cosy 6 caps at properties with measured heat loss below 5.6kW. Many UK semis and detached homes (especially pre-1990s with limited insulation upgrades) need the Cosy 9 or Cosy 12 instead
- Hardware can only be bought through Octopus's install service - you cannot have an independent installer fit a Cosy 6 if you prefer your own tradesperson
£4,460
Typical price - check Octopus Energy for live pricing.
- Heating capacity 6kW (suits homes with heat loss under 5.6kW)
- Refrigerant R290 (propane, GWP 3)
- SCOP at 50°C flow 3.4
- SCOP at 65°C flow 2.8
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By Editorial team1 min read
- Heating capacity
- 6kW (suits homes with heat loss under 5.6kW)
- Refrigerant
- R290 (propane, GWP 3)
- SCOP at 50°C flow
- 3.4
- SCOP at 65°C flow
- 2.8
- Sound power
- 58–60 dB(A) LWA
- Outdoor unit dimensions
- 855mm W × 1125mm H
- Warranty
- 8-year product, 5-year labour
- Hot water cylinder
- Included in install
- Cosy Pods
- Up to 4 included (temperature + humidity)
- Eligible BUS grant
- £7,500
- Typical net price after BUS
- £4,460