The inventor of the condensing technology, Bosch Termoteknik, answers the frequently asked questions about the condensing technology.

The market share of condensing combi boilers, which is one of the best solutions offered by the constantly improving technology, is gradually increasing. The condensing combi boilers, replacing the conventional combi boilers, enable condensation of the vapour in the flue while heating and convey the generated energy to the heating system. So, compared to the conventional heating appliances, they save a considerable amount of energy depending on climate, operating and building conditions.

As the inventor of the condensing technology, Bosch has offered economical products without compromising on quality in light of the experience it has gained since 1895. The fully modulated fan in the Bosch condensing combi boilers automatically increases or decreases its speed according to the heating needs of the room. This way, appliance efficiency increases with the combustion efficiency. Bosch Thermoteknik specialists are answering questions related to the topics of different types of condensing technologies.

The designs of condensing combi boilers make a difference

Different industrial designs that utilize condensing technology can be used in heating appliances. . One of the methods used to utilize the condensing technology is to design the entire combustion chamber of the combi boiler to be suitable for condensation. The advantage of this design is the compact appliance structure and relatively higher operating efficiency. In a design with a conventional combustion chamber that has a condensing economiser, a condensing economizer located on the flue gas line in the combi boiler can be utilized. An advantage in investment cost is provided upfront and the efficiency value may be lower compared to the previously mentioned design. However, more important at this point are the appliance efficiency yield values specified by the manufacturers. . Even though these types of products are called "semi-condensing" in the combi boiler industry, it is an alternative solution to utilize the efficiency derived from the condensing process.

Bosch exclusive design: Condens 2000 series

The Condens 2000 series, which is one of the most important products in the Bosch product portfolio, has a condensing economiser and as an added benefit to this Bosch brand-specific design, cold domestic water is directly preheated at the combi boiler inlet, providing the benefit achieved from condensing in both summer and winter (even in summer months when only hot water is required). With this feature combi boilers use latent heat due to the contact of the flue gas directly both with the heating circuit and the mains water (hot domestic water) and covers the operating principle corresponding to the "double condensing" concept. This operation requires that hot domestic water is preheated at 3-5°C in the first stage. The effect of this recovery is revealed only when a need for hot water arises. Since the energy consumed for the domestic water has a fairly low share in the total consumption, it is not the only criterion in selecting combi boilers (you can find a rate according to your own consumption habits by comparing the summer and winter bills).

Note the seasonal efficiency yield value in selecting a combi boiler

In selecting a condensing combi boiler, Bosch recommends that you first analyse the seasonal efficiency yield values of the appliance and make sure that the appliance can be operated with modulation according to the room temperature during the heating operation and be equipped with compliant modular room controllers accordingly. This way, the heating operation, which contributes greatly to the overall energy consumption can be selected in the most efficient manner. Therefore, the use modulated room controllers that provide precise room temperature control with advanced technology in all condensing combi boilers is recommended.