Homeowners Professionals
Vitobloc 300

Compact, quiet, economical

Vitobloc 300

Type NG 15/NG 20

Combined heat and power unit for natural gas and LPG operation

Electrical output: 15 or 20 kW
Thermal output: 38.3 or 46.5 kW
Smooth running 4-cylinder engines
H₂ ready 20 %
Electrical output

15 kW (type NG 15) or 20 kW (type NG 20)

Thermal output

38.3 kW (type NG 15) or 46.5 kW (type NG 20)

Smooth running 4-cylinder engines

For low sound emissions

H₂ ready

Blends of 20 % hydrogen possible

Suitable for various fuels

Natural gas, bio natural gas, LPG

Optimum ratings for many applications

Small businesses, apartment buildings, hotels, restaurants, car dealerships, commercial nurseries and swimming pools

Low maintenance costs

Due to long maintenance intervals of 8000 hours run

Completely ready-to-connect

Plug and play design

Reduced installation work

Through water-cooled generator

Meet strict TAB conditions

Compliant with the strict technical connection conditions (TAB) of power supply utilities in Germany

Tested to VDE AR-N 4105

With integral GS protection


CHP control system developed by Viessmann

Integral LAN interface

For remote monitoring

Flexible setting of parameters

Tailored to system-specific requirements

Integral heating water pump

For charging a heating water buffer cylinder

Flexible hydraulic connection

And very high flow temperatures

Particularly economical generation of power and heat with CHP units

What could be more economical than using primary energy to generate two types of secondary energy at the same time? This is possible with cogeneration, where combined heat and power units (CHP units) supply electricity and heat at the same time. They are an ideal way to meet the requirements of the energy transition. Economical, efficient and decentralised. Compared to the separate generation of power and heat, they also have considerably higher efficiency.

Vitobloc 300 NG 15/NG 20: economical and efficient

The new compact Vitobloc 300 NG 15 and NG 20 (NG = natural gas) CHP units from Viessmann differ in their electrical and thermal output (15 kWel/38.3 kWth; 20 kWel/46.5 kWth).

Vitobloc 300 – compact, quiet and supplied ready-to-connect

Vitobloc 300 NG 15 and NG 20 are compact, ready-to-connect units with water-cooled synchronous generators for producing three-phase power and heating water. With their low operating noise of less than 54 dB(A) and small space requirement, they are recommended for a broad scope of applications, such as in new build and modernisation projects. The certified CHP units are equipped with integral grid and system protection as standard and are designed for mains substitution mode.

Meets the connection requirements of power supply utilities

The units meet the stringent current and future technical connection conditions (TAB) of power supply utilities in Germany. Thanks to the intelligent electronic platform, the power supply phase (cos phi) can be shifted via the software. This eliminates the need for additional hardware modifications.

Equipped for the future

The technology that enables the use of natural gas/hydrogen blends for heating buildings is already available and on the market in many thousands of cases. In principle, the Vitobloc 300 type NG 15/NG 20 CHP units can already be operated with 20 percent hydrogen today. Opting for this advanced CHP unit is an excellent way to prepare for the future.

Special features of the Vitobloc 300

Maintenance is only required after every 8000  hours run. This means that just one annual service is usually sufficient.

The pipework is pre-assembled at the factory and insulated where necessary. It connects the most important elements of the CHP unit (coolant heat exchanger, exhaust gas heat exchanger and engine). For the purpose of vibration isolation, all pipe joints are provided with metal expansion joints or flexible hose connections and are designed as flanged or flat-gasket threaded connections. The engine is filled at the factory with a water/glycol mixture, circulated by an electric coolant pump, to protect against corrosion.

The integral condensing technology enables overall efficiency of up to 107  percent. The resulting low exhaust gas temperature means that an inexpensive plastic exhaust system can be used. This simplifies the hydraulic connection and a return temperature raising facility is not required.

New electronic platform with innovative functions

The electronic platform with the ViNCI module developed by Viessmann is used to control the CHP unit. The core element of the control unit is a Linux-based industrial computer. This allows connection to innovative remote services and interfaces for communication in multi mode systems and building management systems (BMS). Cloud-based data management meets the highest security standards. The system naturally allows remote web-based visualisation and operation on professional backend solutions.

Vitobloc electronic platform
  • Monitoring and visualisation by app via web-based access
  • Control and monitoring of mains parallel mode and island mode
  • Control and monitoring of heat-led or power-led operation
  • Remote access (remote setting of parameters and event acknowledgement)
  • Flexible setting of parameters according to system-specific requirements
  • Integral load control, e.g. for self-supply
  • Integral, flexibly expandable grid code regulations
  • Increased number of sensors, e.g. heating water pressure, generator temperature, electronic high limit safety cut-out for exhaust gas, etc.
  • Fast data recording and storage in milliseconds
  • Integral colour touchscreen
  • Easy expansion with decentralised electronics modules
7 inch colour touchscreen of the Vitobloc 300
  • 1 x LAN for internet connection (TC-LAN)
  • 1 x external CAN for further decentralised electronics modules (e.g. buffer management)
  • 1 x LAN for Modbus TCP (e.g. for BMS)
  • 1 x RS232 for Modbus RTU (e.g. for BMS)
  • 1 x RS485 for Modbus RTU (e.g. for BMS)
  • 1 x USB for updates and parameter export
  • Continuous information about the system status
  • If required, evaluations and optimisations based on operating data
  • Convenient operation from anywhere
  • Flexible implementation of project-specific requirements, e.g. integration of additional sensors, implementation of utility-specific connection conditions (TAB)
  • Fast response times of the CHP service team when connecting the CHP unit to the TC-LAN system
  • Early detection and elimination of potential sources of error
  • No need for on-site service calls with the associated costs High availability and reliability

Remote access via professional interfaces

The Vitobloc electronic platform enables monitoring of the CHP units from anywhere. Useful conclusions can be drawn about potential optimisation measures while the unit is operational, which can help to boost efficiency.

The available data enables better planning of servicing work and faster responses by the CHP service team. With remote access, on-site maintenance is no longer needed, which saves on costs and increases the availability and reliability of the CHP unit.

Product details


Type NG 15 or NG 20

Electrical output

  15 or 20 kW

Thermal output

38.3 or 46.5  kW

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