Gas Condensing Boiler CGB-2
CGB-2-38 / CGB-2-55

With the new WOLF gas condensing boiler CGB-2-38/55, you receive the most robust heat source in its performance class. Featuring an appealing WOLF design, the unit was developed specially for long operating times with maximum demands. Longevity, operational reliability, maximum efficiency and the highest component quality make the CGB-2-38/55 a workhorse among gas condensing boilers.

Nine convincing arguments
for you and your customers

Consistently robust

The CGB-2-38/55 was developed for especially long runtimes, which can put a boiler to the test, particularly for DHW service in a multi-unit building. The robot-welded V4A fined tube heat exchangers optimized for 38 and 55 kW have 7 times the surface area of smooth tube heat exchangers. The advantage: minimal material stress even at high thermal loads.

Peak Performance

10% higher output compared with the predecessor model provides extra security in the event of demand spikes. The modulation range is also greater, and the units can modulate down to 15% of the nominal output, resulting in less cyclic operation and optimal comustion. In summary: Extra-reliable, efficient and long-lasting.

Many possible applications

Multi-unit residental buildings, offices or industrial buildings: Cascades of up to five units ensure very high operational reliabilty and modulation. Simple integration into BMS systems, pump spread control for optimization of the condensing operation and uncomplicated conversion to natural gas LL or LPG make the CGB-2 38/55 a true allrounder.

Maximum accessibility with
minimal footprint

Up to 55 kW in a compact space and yet still entirely accessible from the front. Minimum side spacing of just 4 cm allows installation in nearly any situation. The removable casing cover creates maximum open space for maintenance.

Improved combustion chamber:
The WOLF solution

From the combustion chamber cover to the condensate pan - the focus is on robust, long-lasting designs and materials with outstanding corrosion properties. New, improved materials such as vermiculite (natural clay mineral) and the cyclone inflow ensure particularly clean and stable combustion.

Installation and assembly as
easy as could be desired

Despite the solid design, the unit is easy to move at 47 kg. The hydraulic connections are entirely compaible with previous models. Existing boilers can be easily replaced thanks to intelligently planned accessories. The commissioning assistant helps ensure fast and easy configuration.

Convenient, fast maintenance

The low, open structure was developed in cooperation with expert technicins. Servicing can take place under system pressure, as usual. Thanks to the intelligent design, the seals require no silicone grease. In other words: Maintenance of the boiler is as clean as operation.

Extensive features and
optimized part management

Everything already integrated: e.g. modulating HE pump, flo rate sensor (less cycling, optimal setting) and flue gas exhaust return damper (for flue gas cascades). WOLF's typical, practical accessory and replacement parts management round out the features perfectly.

WOLF CGB-2-38/55 - Networking

Practical control and simple networking

The WRS-2 control system with the BM-2 programming unit allows the heating system to be combined with he most recent and future generations of WOLF products (Hybrid +). Remote diagnosis and optimization are also no problem thanks to the Smartset portal and app with the integrated WOLF Link home.

performance data
at a glance

Rated heating output at 80/60 °CkW5.3 - 34.9 7.8 - 51.1
Rated heating output at 50/30 °CkW6.3 - 389.2 - 55
Central heating efficiency
Energy efficiency class-AA
heightmm790        790         
Connection of flow and returnG1 1/4"1 1/4"
Balanced flue connectionmm80/12580/125
Max. Overall positive pressure, heatingbar66
Total weight (empty)kg4747
IP Rating-IP X4DIP X4D
Indoor sound power level db (A)5255
Available gas fan draughPa159164

 We provide no guarantee as to the correctness of the information supplied.


When it comes to building services, if you invest in quality, you need to be confident that it's for the long term. Find out here how to get our 5 year system guarantee and what requirements need to be met.

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