PowerGuide

Octopus Cosy 6 vs Vaillant aroTHERM Plus

A side-by-side look at the Octopus Cosy 6 and Vaillant aroTHERM Plus. Winning figures are highlighted.

Octopus Energy
Octopus Cosy 6
Vaillant
Vaillant aroTHERM Plus
Price from
Heat output 6 kW 7 kW
Efficiency (SCOP) 4.1 4
Max flow temp 65 °C 65 °C
Refrigerant R290 R290
Noise 42 dB 46 dB
Min operating temp -20 °C -25 °C
Type Monobloc Monobloc
Warranty 7 yrs 10 yrs

Octopus Cosy 6

The value disruptor. Octopus's bundled install plus the grant can make a heat pump astonishingly cheap, and the Cosy 6 itself is a capable R290 unit. Best if you're an Octopus customer.

Full Octopus Cosy 6 review →

Vaillant aroTHERM Plus

Our top pick for most homes. The R290 refrigerant hits high flow temperatures without wrecking efficiency, so it works in older properties that haven't had radiators upsized. Long warranty seals it.

Full Vaillant aroTHERM Plus review →

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