PowerGuide
NIBE

NIBE S1255

A4.5 6kW
NIBE S1255

A premium Swedish ground-source system with one of the highest SCOPs available and excellent smart controls.

6kW
Heat output
4.7
Efficiency (SCOP)
65°C
Max flow temp
R407C
Refrigerant
43dB
Noise

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PowerGuide scoreA4.5 / 5How we score

Our verdict

About as efficient as home heating gets. If you're committing to groundworks anyway, the S1255's SCOP and controls justify the premium for many self-builders and deep retrofits.

Good

  • Class-leading SCOP up to ~4.7
  • Excellent controls
  • Premium build

Watch out

  • Expensive
  • Older refrigerant

Specifications

Heat output 6 kW
Efficiency (SCOP) 4.7
Max flow temp 65 °C
Refrigerant R407C
Noise 43 dB
Warranty 7 yrs

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