Buderus Logamax plus GB172i.2-25

Product detailed description

Buderus Logamax plus GB172i.2 - 25

- condensing gas boiler with the option to connect a storage tank

- output: 25 kW

We present to you the newest gas boiler from Buderus, the second generation of the Logamax Plus GB172i.2 range, which was developed as an improved version of the Logamax Plus GB172 range and a replacement for the GB072 range, which has been discontinued. The Buderus Logamax Plus GB172i.2 wall-mounted gas condensing boiler is an ideal heating and hot water preparation solution for family homes and flats, while being compatible with Buderus heat pumps to create hybrid systems. It features a modern colour touch display with detailed information on the operating status and faults. The heart of the new range is the innovative WB6 heat exchanger, which achieves an energy efficiency of up to 94% and a higher seasonal efficiency in energy class A+.

Energy cost savings

• A robust, latest-generation, high-efficiency pump with high energy efficiency (class A).
• Thanks to wide modulation (1 : 10), the boiler can smoothly adapt its output to the current heat demand. Lower gas consumption means lower energy costs for the household.

Easy replacement for both standalone and combined operation

• Compatible connections and small dimensions – the Logamax plus GB172i.2 is an ideal solution for a quick replacement when modernising an existing heating system.
• The unit can be operated with a hydrogen admixture of up to 20 %.
• At the same time it is also ready for combined operation with a heat pump for an even more economical and climate-friendlier heating solution for your household.

Smart and economical control

• The built-in BC30.2 control unit with a colour touch display ensures quick access to all important information on the operating status.
• An integrated slot for inserting the MX100, MX200 and MX300 modules enables wireless communication via the Logamatic TC100.2 controller or control via the MyBuderus mobile app.

Technical data:

• Thermal output range at 50/30 °C - 3,4 - 25,0 kW
• Thermal output range at 80/60 °C - 3,0 - 24,0 kW
• Maximum thermal output for DHW - 29,4 kW
• Noise level - 45 dB(A) 
• Energy efficiency class - A
• Seasonal space heating energy efficiency - 94%
• Indoor sound pressure level - 45 dB
• Dimensions (w x d x h) - 440 x 365 x 780 mm
• Weight (without packaging) - 47 kg

Frequently Asked Questions

• How exactly do I choose the output of a BUDERUS condensing boiler? The basis is the calculated heat loss of the heated building (most reliably from the project documentation or an energy certificate). If you don't have a project, you can roughly estimate around 60-100 W per m² of floor area for a commonly insulated house built after 2000, or 100-150 W/m² for an older, uninsulated house - the exact figure, however, differs depending on the number of floors, ceiling height, number and quality of windows, and building orientation. An oversized boiler switches on and off more often (so-called cycling), which shortens its lifespan and reduces efficiency; an undersized boiler, on the other hand, cannot heat the house sufficiently on freezing days.
• Why is a condensing boiler more economical than a conventional one? A condensing boiler additionally uses the heat hidden in the water vapor generated when burning gas - in a conventional boiler this heat leaves unused through the flue, while in a condensing boiler it is cooled below the so-called dew point, the vapor condenses, and the released heat is returned to the heating circuit. Thanks to this, condensing boilers achieve an efficiency of approximately 105-110% relative to the calorific value of the gas, compared to the usual 85-92% for conventional boilers.
• What type of flue gas extraction does this boiler need? Most modern condensing boilers are so-called turbo units (with a sealed combustion chamber) and require a coaxial (concentric) or separate flue gas extraction and combustion air supply routed through the exterior wall or roof - so they do not need a functional chimney. You will find the exact type and maximum length of the flue duct (depending on the diameter, 60/100 or 80/125 mm) in the technical documentation for the specific model, or you can consult our customer service.
• What does the ErP energy class stated for the boiler mean? This is a mandatory efficiency label for heating appliances under the EU ErP (Ecodesign) directive, similar to the energy labels on refrigerators. Condensing boilers commonly achieve class A, or higher in combination with room control (e.g. A+ when using weather-compensated control and a room thermostat).
• Can I install and connect this boiler myself? No. Connection to the natural gas supply, the electrical network, and the flue gas extraction is by law reserved exclusively for a person with the relevant authorization (most often an authorized service technician of the given brand or a gas appliance inspection technician). After installation, the boiler must be commissioned by the manufacturer's authorized service, which is usually also a condition for warranty validity.
• What about service and warranty? Most manufacturers require a regular annual service inspection by an authorized service provider in order to maintain the warranty even after its standard expiry (an extended warranty subject to regular servicing is common especially for the brands Vaillant, Protherm, Viessmann). You will find the exact warranty terms in the warranty certificate supplied with the boiler.
• What is included in the delivery of this specific product? The exact package contents (the boiler itself, possibly a hot water storage tank, room control, and other accessories in the case of a set) are stated in the product name and in its technical parameters above on this page.