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ViessmannVitocal 250-A AWO-M-E-AC 251.A04

Viessmann Vitocal 250-A AWO-M-E-AC 251.A04
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The Viessmann Vitocal 250-A AWO-M-E-AC 251.A04 is an air-to-water heat pump with a SCOP of 4.57 (35 °C) and a sound power level of 46 dB(A).1

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SCOP (35 °C)
4.571

Seasonal efficiency: how much heat you get per kWh of electricity across a heating season.

Heating capacity (A7/W35)
4kW1
Official source
Outdoor unit sound power
46dB(A)1
Official source
Refrigerant
R2901
Official source
Type (source)
Air-to-water1
Official source

Technical specifications

General
Type (source) Air-to-water1
Performance
Heating capacity (A7/W35) 4 kW1
Rated output 35 °C 4.08 kW1
Rated output 55 °C 3.77 kW1
Min. outdoor temperature -20 °C1
Efficiency
SCOP (35 °C) 4.571
SCOP (55 °C) 3.331
Seasonal efficiency ηs 35 °C 180 %1
Seasonal efficiency ηs 55 °C 130 %1
Energy label 35 °C A, , , 1
Energy label 55 °C A, , 1
COP A7/W35 5.11
Noise
Outdoor unit sound power 46 dB(A)1
Indoor unit sound power 40 dB(A)1
Refrigerant
Refrigerant R2901
Refrigerant GWP 31
Refrigerant charge 1.2 kg1

Variants

This model is registered in 21 combinations (for example with a different indoor unit or cylinder) with exactly the same performance. All figures on this page apply to each of these types. The part of the type number that differs is in bold; small differences (e.g. cylinder volume or anode) are listed after it:

  • Vitocal 250-A AWO-M-E-AC 251.A04
  • IDU-A Compact 2C AWMIT.A1.19-V056 / ODU 250-A AWMOF-251.A1.04-230-V002
  • IDU-A Compact AWMIT.A1.19-V053 / ODU 250-A AWMOF-251.A1.04-230-V002
  • IDU-A Modular AWMIW.A1.19-V051 / ODU 250-A AWMOF-251.A1.04-230-V002
  • Vitocal 250-A AWO-M-E-AC 251.A04 2C
  • Vitocal 250-A AWO-M-E-AC 251.A04 2C SP
  • Vitocal 250-A AWO-M-E-AC 251.A04 SP
  • Vitocal 250-A AWO-M-E-AC-AF 251.A04
  • Vitocal 250-A AWO-M-E-AC-AF 251.A04 2C
  • Vitocal 250-A AWO-M-E-AC-AF 251.A04 2C SP
  • Vitocal 250-A AWO-M-E-AC-AF 251.A04 SP
  • Vitocal 250-AH HAWO-M-AC 252.A04
  • Vitocal 250-AH HAWO-M-AC-AF 252.A04
  • Vitocal 252-A AWOT-M-E-AC 251.A04
  • Vitocal 252-A AWOT-M-E-AC 251.A04 2C
  • Vitocal 252-A AWOT-M-E-AC 251.A04 2C SP
  • Vitocal 252-A AWOT-M-E-AC 251.A04 SP
  • Vitocal 252-A AWOT-M-E-AC-AF 251.A04
  • Vitocal 252-A AWOT-M-E-AC-AF 251.A04 2C
  • Vitocal 252-A AWOT-M-E-AC-AF 251.A04 2C SP
  • Vitocal 252-A AWOT-M-E-AC-AF 251.A04 SP

Manufacturer documentation

  • Datasheet / specifications — VITOCAL 250-A Luft/Wasser-Wärmepumpen mit Innen- und Außeneinheit – Datenblatt (4/2025) (viessmann.de, PDF)

External links to Viessmann's official website. The manufacturer may change or move documents; where they differ, the manufacturer's latest version applies.

Frequently asked questions

Which refrigerant does the Viessmann Vitocal 250-A AWO-M-E-AC 251.A04 use?

The Viessmann Vitocal 250-A AWO-M-E-AC 251.A04 uses R290.1

Sources

  1. Heat Pump Keymark certificates — EHPA / DIN CERTCO (Heat Pump KEYMARK) · accessed 29 Sept 2026