The condensing boiler represents a major innovation in the world of residential heating. This technology, increasingly adopted by French households, is transforming the way we use energy for heating while helping to reduce our carbon footprint.
How a Condensing Boiler Works
The condensing boiler stands out for its ability to maximize fuel use, whether gas or oil. Its operation is based on an ingenious mechanism that transforms heat normally lost into usable energy.
How Condensing Technology Recovers Energy
Condensing technology captures the heat contained in the water vapor produced during combustion. In a traditional system, this vapor escapes through the chimney, carrying with it a significant amount of thermal energy. The condensing boiler, on the other hand, cools this vapor sufficiently to transform it into liquid water (condensation), thus releasing the latent heat it contains. This energy recovery explains the advantages of the condensing boiler, which can achieve a theoretical efficiency greater than 100% compared to the lower calorific value of the fuel.
Difference from traditional boilers
Traditional boilers release high-temperature flue gases (around 150-200°C) without exploiting their energy potential. Condensing boilers lower the temperature of these flue gases to around 50-60°C, recovering up to 30% additional energy. This THPE (Very High Energy Performance) technology requires a specific evacuation of the acidic condensates produced, generally to wastewater. Another major distinguishing feature is the flue gas evacuation system, which can be installed via a flue or flue-type chimney, thus adapting the installation to the constraints of the home.
Savings achieved with a condensing boiler
The condensing boiler represents a modern solution for home heating. This technology uses an innovative principle: it recovers the heat contained in the water vapor produced during gas combustion. This heat recovery process gives it an efficiency of over 100%, whereas traditional boilers only achieve 80 to 90%. Let’s see what concrete savings this technology can bring to your home.
Reduced energy consumption
The condensing boiler stands out for its ability to significantly reduce energy consumption. Thanks to its heat recovery mechanism from combustion fumes, it generates savings of up to 30% compared to a conventional gas boiler. This performance is due to its ability to utilize the thermal energy usually lost in conventional systems. The THPE (Very High Energy Performance) system guarantees an ETAS of over 92%, maximizing fuel utilization. To maximize these savings, it is advisable to pair the boiler with a room thermostat and a temperature sensor. This combination with hydraulic underfloor heating or low-temperature radiators increases the overall efficiency of the central heating system, further reducing energy bills.
Financial assistance is available for installation.
Despite a higher initial investment than a standard boiler, several devices can reduce the acquisition cost of a condensing boiler. The reduced VAT rate of 5.5% for purchase and installation represents an immediate initial savings. The zero-interest eco-loan is an advantageous financing solution for homeowners wishing to make this energy transition. Local subsidies may also exist depending on your place of residence: inquire at your town hall or departmental council. Note that to benefit from this assistance, the installation must be carried out by an RGE (Recognized Environmental Guarantor) certified professional, such as Engie. It should be noted that certain subsidies such as MaPrimeRénov’ and Energy Savings Certificates are no longer available for this type of equipment since 2023 and 2024 respectively. Condensing boilers are no longer authorized in new constructions, as regulations now favor other heating solutions that emit less CO2.