Wall-mounted condensing boiler with instantaneous hot water heating BOSCH Condens GC2300iW 22/25 C

Product detailed description

Frequently Asked Questions

• How exactly do I choose the output of a BOSCH condensing boiler? The basis is the calculated heat loss of the heated building (most reliably from the project documentation or 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, non-insulated house - the exact figure, however, varies depending on the number of floors, room height, the number and quality of windows, and the orientation of the building. A boiler oversized in output switches on and off more frequently (so-called cycling), which shortens its service life and reduces efficiency; conversely, an undersized boiler cannot sufficiently heat the house on frosty days.
• Why is a condensing boiler more economical than a conventional one? A condensing boiler additionally utilises the heat hidden in the water vapour produced during gas combustion - in a conventional boiler this escapes unused through the flue, whereas in a condensing boiler it is cooled below the so-called dew point, the vapour 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 a typical 85-92% for conventional boilers.
• What type of flue gas extraction does this boiler need? Most modern condensing boilers are so-called turbo boilers (with a sealed combustion chamber) and require either a concentric (coaxial) or separate flue gas discharge and combustion air supply routed through the outer wall or roof - so a functioning chimney is not needed. The exact type and maximum length of the flue (depending on the 60/100 or 80/125 mm diameter) can be found in the technical documentation for the specific model, or you can consult our customer service.
• What does the ErP energy class shown for the boiler mean? This is a mandatory efficiency label for heating appliances under the EU ErP (Ecodesign) directive, similar to the energy labels used for refrigerators. Condensing boilers commonly achieve class A, or even higher in combination with room controls (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, electrical network and flue gas extraction is by law reserved exclusively for a person with the relevant authorisation (most often an authorised service technician of the given brand or a gas appliance inspection technician). After installation, the boiler must be commissioned by the manufacturer's authorised service, which is usually also a condition for the warranty to be valid.
• What about service and warranty? Most manufacturers require a regular annual service inspection by an authorised service provider in order to keep the warranty valid even after its standard expiry (an extended warranty for regular servicing is common especially with the brands Vaillant, Protherm and Viessmann). The exact warranty terms can be found in the warranty certificate supplied with the boiler.
• What is included in the delivery of this specific product? The exact contents of the package (the boiler itself, possibly a hot water cylinder, 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.