Best Air Source Heat Pumps UK 2026 — comparing the top 5

Air-source heat pumps for UK homes. Eligible for the £7,500 Boiler Upgrade Scheme grant.

Compiled by Sepehr · Last reviewed May 2026

What to look for in an air-source heat pump

SCOP, not COP: The headline COP figure is measured in perfect lab conditions. The Seasonal Coefficient of Performance (SCOP) reflects real-world UK performance across a heating season — this is the number that actually determines your energy bills. Anything above 3.5 SCOP is strong for UK conditions.

Flow temperature compatibility: A heat pump running at 45°C flow temperature is significantly more efficient than one running at 55°C. This matters if you have existing radiators — they may need upsizing if they were designed for a 70°C boiler flow. Underfloor heating runs at 35–45°C and is ideal.

Boiler Upgrade Scheme: The £7,500 BUS grant is available to homeowners replacing a fossil fuel heating system. All products on this page are BUS-eligible — your MCS-certified installer handles the application. Check you meet the criteria (no outstanding Green Homes Grant, EPC below E) before booking.

Noise: Heat pumps run continuously rather than in short bursts like boilers. The sound output — typically 45–52dB(A) at 1m — matters more than boiler noise because it's constant. If your unit will sit close to a neighbour's window or bedroom, prioritise the quieter models.

Common mistake: Installing a heat pump into a poorly insulated home and being surprised by high bills. A heat pump extracts ambient heat efficiently — but if your home loses heat quickly, you'll run it continuously. The MCS Domestic Heat Pump Installer standard requires a heat loss survey before installation.

7.9

Daikin Altherma 3 R 8kW

Compact monobloc design with integrated controls. One of the tidier-looking units on the market, with a well-regarded app and strong SCOP.

~£14,200 installed (after £7,500 BUS grant: ~£6,700)

7.6

Bosch Compress 7000i AW 8kW

Solid mid-market option with a familiar brand and competitive pricing. Good SCOP and a straightforward install profile.

~£13,000 installed (after £7,500 BUS grant: ~£5,500)

8.1

Worcester Bosch Compress 7000i AW 8kW

Worcester Bosch air-source heat pump with R290 refrigerant. Familiar brand to UK homeowners, large installer network, and a competitive 7-year warranty.

~£13,800 installed (after £7,500 BUS grant: ~£6,300)

8.5

Vaillant arotherm plus 8kW

German-engineered ASHP with A+++ energy rating and among the lowest noise outputs in class at 46dB(A). Eligible for the Boiler Upgrade Scheme grant.

~£14,500 installed (after £7,500 BUS grant: ~£7,000)

8.0

LG ThermaV R32 9kW

Strong value proposition — competitive SCOP with one of the more aggressive installed prices. Good smart integration via LG ThinQ.

~£12,500 installed (after £7,500 BUS grant: ~£5,000)

Popular head-to-heads in heat pumps

Side-by-side comparisons of the most-quoted pairings.

Vaillant aroTHERM Plus vs Mitsubishi Ecodan

R290 refrigerant vs the most-installed UK ASHP — quieter and warmer flow.

Daikin Altherma 3 vs Vaillant aroTHERM Plus

Compact monobloc vs high flow-temperature R290 — sizing the right unit.

LG ThermaV vs Samsung EHS Mono HT Quiet

Korean rivals on SCOP, noise, and installed price after the £7,500 BUS grant.