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Gas condensing boilers

CGB-2 family

The CGB-2 series of WOLF gas condensing boilers covers the entire spectrum of gas condensing technology: from straightforward gas heating systems to combi boilers and models with integrated DHW storage cylinders.

Versatile and flexible

  • CGB-2

    The WOLF CGB-2 gas condensing boiler is the basic model. This gas heater covers heating output ratings of 14, 20 or 24 kW with the models CGB-2/14, CGB-2/20 and CGB-2/24.

    Basic information

    Dimensions (WxHxD) 440mm x 790mm x 378mm

    Seasonal space heating energy efficiency ηS 93

  • CGB-2K

    The CGB-2K combines central heating with integrated DHW heating. The gas condensing combi boiler is available with 20 or 24 kW heat output in the models CGB-2K/20 and GCB-2K/24.

    Basic information

    Dimensions (WxHxD) 440mm x 790mm x 378mm

    Seasonal space heating energy efficiency ηS 93

  • CGS-2L

    The CGB-2L model is a freestanding unit with an integrated floorstanding stratification cylinder. The CGB-2-14/120L offers 14 kW of heating output and 120 litres storage capacity.

    The CGB-2-20/160L has a storage capacity of 160 litres and generates 20 kW heating output. The CGB-2-24/200L has an output of 24 kW and a capacity of 200 litres.

    Basic information

    Energy efficiency class for DHW heating A

    Dimensions (WxHxD) 600mm x 1462mm x 635mm

    Seasonal space heating energy efficiency ηS 93

  • CGS-2R

    The CGB-2R gas condensing boiler is the best solution if your water is particularly hard. This is because the indirect coil heat exchanger in the integrated cylinder protects the system against scaling.

    The models CGB-2-14/150R, CGB-2-20/150R and CGB-2-24/150R have an output of 14, 20 or 24 kW and all have a storage capacity of 150 litres.

    Basic information

    Energy efficiency class, DHW heating A

    Seasonal space heating energy efficiency ηS 93

    Dimensions (WxHxD) 600mm x 1792mm x 635mm

  • CGW-2L

    The wall-mounted version of the CGW-2L is also equipped with a wall-mounted cylinder. The models CGB-2-14/100L, CGW-2-20/120L and CGW-2-24/140L have a heating output of 14, 20 or 24 kW and storage capacities of 100, 120 or 140 litres.

    Basic information

    Dimensions (WxHxD) 790mm x 800mm x 378mm

    Energy efficiency class, DHW heating A

  • CSZ-2R

    The CSZ-2R gas condensing solar centre is designed for combination with solar thermal collectors. The models CGZ-2-14/300R, CGZ-2-20/300R and CGZ-2-24/300R have a heating output of 14, 20 or 24 kW. The solar cylinders of all three models hold 300 litres.

    Basic information

    Dimensions (WxHxD) 1850mm x 600mm x 1013mm

  • CGB-2-38/55

    The CGB-2-38/55 gas condensing boiler is suitable for older buildings or apartment blocks thanks to its ample output of 38 or 55 kW. The boiler is the most robust in its performance class.

    It was developed for especially long runtimes and particularly for DHW heating in multi-unit buildings, which can put any boiler to the test.

    Basic information

    Seasonal space heating energy efficiency ηS 94

    Dimensions (WxHxD) 440mm x 790mm x 412mm

WOLF gas heating systems offer numerous benefits

High efficiency - man relaxing on the couch

Space-saving and flexible

Even fit in smaller rooms

The slim design of CGB gas condensing boilers means that they even fit into small utility rooms and attics. This applies to both the floorstanding and wall-mounted appliances. Read more

Can use many types of gas

The CGB series is, of course, designed to use all conventional types of gas. It can even use LPG if your house is not connected to the gas mains. CGB-2 appliances can also use biogas as long as it meets the specifications for natural gas.

Moreover, most of the models in the series are already H2-ready: they are equipped to burn a mixture of natural gas and hydrogen, which will become more widespread in the future. Read more

New building sectional view

Expandable system

Combine with renewable energies

All WOLF gas condensing boilers can be combined with renewable energies for particularly environmentally conscious, efficient and cost-saving heating.

Control all WOLF appliances

Gas condensing boilers, solar thermal systems, heat pumps and mechanical ventilation: WOLF system modules are perfectly coordinated and can be operated from a shared control system. They can even be controlled via smartphone app. Read more

Gas condensing boiler CGB-2 open

Robust and durable

Tried-and-tested for many years of service

The robust heat exchanger of the CGB series guarantees a long appliance service life. Gas condensing technology is also well established and has proven itself many times over.

Reliability for new and old buildings

The CGB series has the right heating system for any project, from brand new buildings to updated heating systems in old buildings.

Technical details

  • CGB-2

    CGB-2-14
    CGB-2-20
    CGB-2-24
    Min./max. rated heating output at 50/30°C
    kW
    2.1 - 15.2
    4.4 - 20.4
    5.6 - 25.8
    Seasonal space heating energy efficiency ηS
    93
    93
    93
    Width
    mm
    440
    440
    440
    Height
    mm
    790
    790
    790
    Depth
    mm
    378
    378
    378

    CGB-2

    • CGB-2-14

    • CGB-2-20

    • CGB-2-24

      Min./max. rated heating output at 50/30°C
      kW
      2.1 - 15.2
      4.4 - 20.4
      5.6 - 25.8
      Seasonal space heating energy efficiency ηS
      93
      93
      93
      Width
      mm
      440
      440
      440
      Height
      mm
      790
      790
      790
      Depth
      mm
      378
      378
      378
    • CGB-2K

      CGB-2K-20
      CGB-2K-24
      Min./max. rated heating output at 50/30°C
      kW
      4.4 - 20.4
      5.6 - 25.8
      Seasonal space heating energy efficiency ηS
      93
      93
      Width
      mm
      440
      440
      Height
      mm
      790
      790
      Depth
      mm
      378
      378

      CGB-2K

      • CGB-2K-20

      • CGB-2K-24

        Min./max. rated heating output at 50/30°C
        kW
        4.4 - 20.4
        5.6 - 25.8
        Seasonal space heating energy efficiency ηS
        93
        93
        Width
        mm
        440
        440
        Height
        mm
        790
        790
        Depth
        mm
        378
        378
      • CGS-2L

        CGS-2-14 / 120L
        CGS-2-20 / 160L
        CGS-2-24 / 200L
        Min./max. rated heating output at 50/30°C
        kW
        2.1 - 15.2
        4.4 - 20.4
        5.6 - 25.8
        Seasonal space heating energy efficiency ηS
        93
        93
        93
        Width
        mm
        600
        600
        600
        Height
        mm
        1462
        1462
        1462
        Depth
        mm
        635
        635
        635
        Energy efficiency class, DHW heating
        A
        A
        A

        CGS-2L

        • CGS-2-14 / 120L

        • CGS-2-20 / 160L

        • CGS-2-24 / 200L

          Min./max. rated heating output at 50/30°C
          kW
          2.1 - 15.2
          4.4 - 20.4
          5.6 - 25.8
          Seasonal space heating energy efficiency ηS
          93
          93
          93
          Width
          mm
          600
          600
          600
          Height
          mm
          1462
          1462
          1462
          Depth
          mm
          635
          635
          635
          Energy efficiency class, DHW heating
          A
          A
          A
        • CGS-2R

          CGS-2-14 / 150R
          CGS-2-20 / 150R
          CGS-2-24 / 150R
          Min./max. rated heating output at 50/30°C
          kW
          2.1 - 15.2
          4.4 - 20.4
          5.6 - 28.8
          Seasonal space heating energy efficiency ηS
          93
          93
          93
          Width
          mm
          600
          600
          600
          Height
          mm
          1792
          1792
          1792
          Depth
          mm
          635
          635
          635
          Energy efficiency class, DHW heating
          A
          A
          A

          CGS-2R

          • CGS-2-14 / 150R

          • CGS-2-20 / 150R

          • CGS-2-24 / 150R

            Min./max. rated heating output at 50/30°C
            kW
            2.1 - 15.2
            4.4 - 20.4
            5.6 - 28.8
            Seasonal space heating energy efficiency ηS
            93
            93
            93
            Width
            mm
            600
            600
            600
            Height
            mm
            1792
            1792
            1792
            Depth
            mm
            635
            635
            635
            Energy efficiency class, DHW heating
            A
            A
            A
          • CGW-2L

            CGW-2-14 / 100L
            CGW-2-20 / 120L
            CGW-2-24 / 140L
            Min./max. rated heating output at 50/30°C
            kW
            14
            19
            23
            Width
            mm
            790
            790
            790
            Height
            mm
            800
            800
            800
            Depth
            mm
            378
            378
            378
            Energy efficiency class, DHW heating
            A
            A
            A

            CGW-2L

            • CGW-2-14 / 100L

            • CGW-2-20 / 120L

            • CGW-2-24 / 140L

              Min./max. rated heating output at 50/30°C
              kW
              14
              19
              23
              Width
              mm
              790
              790
              790
              Height
              mm
              800
              800
              800
              Depth
              mm
              378
              378
              378
              Energy efficiency class, DHW heating
              A
              A
              A
            • CSZ-2R

              CSZ-2-14 / 300R
              CSZ-2-20 / 300R
              CSZ-2-24 / 300R
              Min./max. rated heating output at 50/30°C
              kW
              4
              19
              24
              Width
              mm
              1850
              1850
              1850
              Height
              mm
              600
              600
              600
              Depth
              mm
              1013
              1013
              1013

              CSZ-2R

              • CSZ-2-14 / 300R

              • CSZ-2-20 / 300R

              • CSZ-2-24 / 300R

                Min./max. rated heating output at 50/30°C
                kW
                4
                19
                24
                Width
                mm
                1850
                1850
                1850
                Height
                mm
                600
                600
                600
                Depth
                mm
                1013
                1013
                1013
              • CGB-2-38/55

                CGB-2-38
                CGB-2-55
                Width
                mm
                440
                440
                Height
                mm
                790
                790
                Depth
                mm
                412
                412

                CGB-2-38/55

                • CGB-2-38

                • CGB-2-55

                  Width
                  mm
                  440
                  440
                  Height
                  mm
                  790
                  790
                  Depth
                  mm
                  412
                  412

                Do you have any questions?

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