Homeowners Professionals
Vitocal 350-G

Ground source heat pump

Ground source heat pump heat pump with the option of water/water operation.

Rated heating output: 20.5 to 42.3 kW
High performance due to two-stage design
Flow temperatures up to 68°C
Low noise and low vibrations
Rated heating output for brine/water operation

20.5 to 42.3 kW (single-stage) and 41.0 to 84.6 kW (two-stage)

Rated heating output for water/water operation

25.4 to 52.3 kW (single-stage) and 50.8 to 104.6 kW (two-stage)

High heating outputs

With two-stage version

Flow temperatures up to 68 °C

Thanks to EVI compressor

Low noise and low vibrations

Due to sound-optimised appliance design

Low running costs due to high COP

Coefficient of performance to EN 14511 of up to 5.0 (brine 0 °C/water 35 °C)

Mono mode operation possible

For heating and DHW

High efficiency at every operating point due to RCD system

Refrigerant cycle diagnostic system in conjunction with electronic expansion valve

Easy to use Vitotronic control unit

With plain text and graphic display

Control unit for weather-compensated heating operation

As well as natural or active cooling

Master/slave solutions for higher heat demands

E.g. combination with the Vitocal 300-G

Consume self-generated power

Thanks to preparation for optimised power consumption from photovoltaic systems

Web-enabled by Vitoconnect

For operation and service via Viessmann apps (accessories)

The Vitocal 350-G achieves a high flow temperature of up to 68 °C and is therefore also suitable for modernisation projects involving radiator heating systems.

Vitocal 350-G: Heat pump with a high flow temperature of up to 68 °C

The powerful Vitocal  350-G brine/water heat pump is one of the quietest heat generators of its kind thanks to its low vibration design.

Where heat demand is even higher, the Vitocal  350-G can be operated in two-stage mode with an additional heat pump of the same type, or with a Vitocal  300-G in a master/slave system, and can then provide an output of up to 84.6  kW. At an early stage when planning the system, this configuration allows for optimum matching of the heat pumps to the building in question.

The Vitocal  350-G achieves high flow temperatures of up to 68 °C. This results from the use of an EVI (enhanced vapour injection) refrigerant circuit, where the injection of vapour cools the refrigerant so that it can be more densely compressed than is otherwise possible. This means that the Vitocal  350-G is also suitable for modernisation projects involving radiator heating systems.


In a master/slave system, the Vitocal  350-G, as the master, delivers high flow temperatures for DHW heating, while the Vitocal  300-G (slave, without its own control unit) covers the required heat load. The EVI refrigerant circuit enables the Vitocal  350-G to achieve a very high COP of up to 5.0, which contributes to its low running costs.

The Vitocal  350-G heat pump is already prepared for cost effective operation with self-generated power from a photovoltaic system. An intelligent control unit ensures maximum consumption of the self-generated power and therefore lowers energy costs.

The EHPA Quality Label serves as proof of the COP (coefficient of performance).  The German EHPA Quality Label Committee has confirmed that Viessmann's Vitocal  350-G heat pump meets EHPA Quality Label requirements.

  • Brine/water heat pump, single-stage heating output: 20.5 to 42.3  kW; two-stage: 41.0 to 84.6  kW
  • Water/water heat pump, single-stage heating output: 25.4 to 52.3  kW; two-stage: 50.8 to 104.6  kW
  • Low running costs with the highest level of efficiency at every operating point through the innovative RCD (refrigerant cycle diagnostic) system with EEV (electronic expansion valve)
  • Energy efficiency class*: A++ / A++

    *In accordance with Commission Delegated Regulation (EU) No  811/2013 for heating; average climatic conditions –– low (35  °C)/medium (55  °C) temperature applications

The integrated range of solutions for the Vitocal 350-G

Benefit from the value added services and digital services of Viessmann's integrated range of solutions.

ViCare app

The ViCare app provides intuitive heating control. Green for go – the user can see at a glance in the app whether their heating system is working as it should.

More about the ViCare app

ViGuide app

ViGuide is an app for trade partners. It has numerous functions for monitoring and controlling systems in both detached houses and apartment buildings and provides rapid access to Technical Service.

More about the ViGuide app


The Vitoconnect is the interface between boiler and app – the prerequisite for heating system operation via smartphone and tablet. It also provides remote system maintenance capability for contractors using the Vitoguide app.

More about the Vitoconnect

Vitotronic  200 control unit with communication capability

Viessmann uses the convenient Vitotronic  200 control unit to ensure standardised operation of all its heat generators. Its many functions include menu-guided operation, an integral diagnostic system, control of the instantaneous heating water heater and an additional (existing) oil or gas boiler, and of course, the natural and active cooling functions.

Furthermore, the Vitotronic  200 is capable of communicating and, via the Vitocom  300 communication module, allows the heat pump system to be set up, monitored and optimised over the internet with the Vitotrol  app on a smartphone or tablet.

Vitotronic 200

Product details

Rated heating output (kW), operating point A7/W35 (to EN 14511)

Type BW/BWS 351.B20: 20.5  kW | type BW/BWS 351.B27: 28.7  kW | type BW/BWS 351.B33: 32.7  kW | type BW/BWS 351.B42: 42.3  kW

Coefficient of performance ε (COP) A7/W35

Type BW/BWS 351.B20: 4.8 | type BW/BWS 351.B27: 4.9 | type BW/BWS 351.B33: 5.0 | type BW/BWS 351.B42: 4.8

Energy efficiency class*

A++ / A++

* In accordance with Commission Delegated Regulation (EU) No  811/2013 for heating, average climatic conditions –– low temperature application (35  °C) / medium temperature application (55  °C)

Energy efficiency class, DHW heating


Application area

Detached houses, two-family houses, apartment buildings, commercial enterprises, local authority premises, new build and modernisation projects


Vitotronic 200 control unit with plain text and graphic display; can be operated via the ViCare app

DHW heating

Additional DHW cylinder required, resulting in a high level of DHW convenience

Additional features

Natural cooling and active cooling functions

Product cross-section
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