How to Choose a Combi Boiler? Expert Advice
20-01-2025
11:46
When choosing a combi boiler , factors such as the square meter of the living area to be used, insulation status, facade and floor where it is located should be taken into consideration. The type of heating system in the house where the combi boiler will be connected to natural gas and the insulation materials used in the structure directly guide the choices. The issues to be considered in the selection of a combi boiler in order to obtain the most efficient heating quality in living spaces and the features that a good device should have are discussed in our article with expert opinion.
Features of a Good Combination
In order to use all systems of natural gas efficiently in living spaces, it is necessary to be careful about choosing a combi boiler . Many details, from the operating system of the combi boiler to the square meter area where it can be effective, are important in terms of obtaining a quality natural gas heating system in interior spaces. It is necessary to examine the combi boilers, which have various features according to the area of use, under several headings.
Condensing Combi Boiler
It is a combi system that exhibits a performance of 103% - 109% in terms of natural gas usage efficiency and savings. Although it is a little more expensive than other combi systems in terms of expense, it is the most ergonomic design in terms of efficiency and long-term performance.
The most misconception about condensing combi boiler systems is that they burn the same gas more than once, creating a toxic situation. The hot water vapor formed after the combustion reaction is separated by the combi boiler and the energy of the hot gas obtained is used once again. Contrary to popular belief, recycling hot energy into the system is an environmentally friendly and healthy practice. 
Electric Combi Boiler
Electric combi boilers, which are the product of new generation technology, are preferred in order to provide the same efficiency in regions where natural gas systems are not available. In electric combi boiler designs, electrical energy is used instead of gas to heat the water. Again, in houses where radiators or floor systems are used, as in natural gas houses, a clean heating is achieved thanks to the combi boiler.
Since there is no risk of gas leakage or poisoning in electric combi boilers, there is no need for a chimney in the design. Although the installation cost of electric combi boilers is high, it is possible to say that the fuel it uses is more affordable than natural gas. Especially in buildings where electricity is obtained by solar energy, it is possible to obtain zero-cost heating with these combi boilers.
Vented Combi Boiler
Vented combi boilers, which have an old-style operating system, use the oxygen in the environment they are in to bring the water to a sufficient temperature. Vented combi boilers heat the water as a result of the combustion reaction inside, and send the resulting harmful and waste gases out through the chimney.
In these products, it is very important to perform the necessary maintenance of the chimneys and use leak-proof materials. Vented combi boilers, which carry the risk of natural gas leakage, can cause dirty gas to fill in during windy and stormy weather. To eliminate the risk, vented combi boilers should be positioned in open areas such as balconies.
Hermetic Combi Boiler
The hermetic system, also known as the conventional combi boiler, has an effective design that provides 93% efficiency. Within the scope of the European Union harmonization law, the production and sale of hermetic combi boiler facilities in Turkey are prohibited. There is no restriction on the use or sale of hermetic combi boiler systems whose production dates are before April 21, 2018. There is no condensation system in hermetic combi boilers with an old system. 
Expert Advice: What Should You Pay Attention to When Choosing Your Combi Boiler?
The main criteria to consider when choosing a combi boiler is the operating system. Combi boilers that manage all heating and hot water systems of the house must be compatible with the square meter and general features of the building. The factors to be considered when choosing a combi boiler are discussed under headings.
Brand Reliability
The first thing to consider when choosing a combi boiler is the services and trust offered by the specified brand. Unknown combi boilers with no authorized service and after-sales service will cause losses in the long term. Cheap brands and products, especially those preferred in terms of price and performance, will cause problems such as inefficiency and inability to find a contact person in the future. Attention should be paid to the warranty periods of the selected combi boiler, and brands that offer a minimum of 2-4 years of warranty should be given priority.
Determining Needs Properly
When choosing a combi boiler, it is necessary to make a choice according to the area of use and need. Factors such as the width of the interior space to be heated, the heating system used in the environment, insulation details and the main material of the structure allow the correct determination of the combi boiler to be selected. A simple calculation is made to determine the features of the most suitable combi boiler for interior spaces such as homes and workplaces.
For the combi m2 calculation , the criteria of the interior space to be heated, the facade it is on, the number of bathrooms and the floor it is on are taken into consideration. If the house where the combi will be purchased faces north, +15 square meters are added to the calculation. This means that the heating capacity of the combi must be calculated 15 square meters less.
Combi Boiler Efficiency and Energy Savings
In order for combi boilers to use energy better, their efficiency and energy saving criteria are evaluated. Combi boiler designs that burn the least allow bills to drop noticeably and spaces to be heated better. It is considered profitable to pay higher amounts at the beginning for efficient combi boilers that can pay for themselves in the long run and reduce bills.
Heating Capacity of the Combi Boiler
The choice of combi capacity is important in terms of providing sufficient efficiency to the radiators and radiators in the environment. Factors such as the number of rooms in the interior, the length of the radiators, the amount of radiators and towel warmers, bathrooms and toilets directly affect the capacity of the combi. It should be said that an apartment with an empty lower and upper floor is more difficult to heat than normal spaces. In such cases, it is more effective to choose products with a higher performance instead of combi boilers suitable for the square meter.
Design and Use of the Device
When choosing a combi boiler, it is recommended to pay attention to details such as programmable thermostat, easy heat adjustment and understandable LCD screen. In particular, the fact that the devices can be controlled with a remote control provides ease of use. 
Combi Boiler Selection Based on Square Metre
By choosing a combi boiler according to the size of the house, efficient heating of living spaces is ensured. Although not scientific, a generally accepted calculation logic is at the forefront for combi boiler calculations per square meter . Calculations are made on an average combi boiler capacity of 1.5-2 kW for every 10 m2 of living space.
The kW value calculated during combi boiler selection may vary depending on the region and climate conditions. The limits determined for combi boiler selection based on square meters and the details to be considered are examined under several headings.
Combi Boiler Selection for a 100 M2 House
In living spaces up to 160 m2, a combi boiler with a capacity of 20,000 kcal/h or 24 kW should be used. Combi boilers with a heating capacity of 20,000 kcal / 24,000 kcal can heat houses with an area of 80-100 m2 to 100-120 m2 and radiators with an equivalent capacity.
200 M2 Duplex House Combi Boiler Recommendation
30 kW combi boilers are preferred in houses with an area between 160 and 200 m2. The large number of rooms in duplex houses and the insulation of the attic floor cause the kW value of the combi boiler to increase. The central heating system used in two-storey houses is not evaluated as in single-storey spaces. While the water pressure is transmitted directly in single-storey houses, a more powerful combi boiler is needed to send the same water to the upper floor.
When choosing a combi boiler for a single-storey flat and a duplex house with the same square meter, the conditions are not the same. It is recommended to use 40 kW combi boilers for houses between 130-210 m2, 41 kW for 220 m2 spaces and 42 kW for 230 m2 areas. In short, it is possible to determine the appropriate combi boiler for the interior by adding +- 1/1.5 kW for every 10 square meters.
When choosing a combi boiler for a single-storey flat and a duplex house with the same square meter, the conditions are not the same. It is recommended to use 40 kW combi boilers for houses between 130-210 m2, 41 kW for 220 m2 spaces and 42 kW for 230 m2 areas. In short, it is possible to determine the appropriate combi boiler for the interior by adding +- 1/1.5 kW for every 10 square meters.
Combi Boiler for 300 M2 House
In indoor areas of 300 m2 and above, combi boilers with a power of 47 kW provide sufficient performance. If the house where the combi boiler will be used is not single-storey, care should be taken to ensure that the device has a higher kW rating.
Combi Boiler Selection According to Radiator Size
The power capacity of the combi boiler to be installed varies depending on the number of radiators and the total length of the radiators used in the space:
● For indoor spaces with radiators between 5 and 9 meters, 24 kW capacity combi boilers are sufficient.
● It is recommended to install 30 kW combi boilers in living spaces where radiators and radiators between 9 and 13 meters are used.
● In interior spaces where a radiator system of 13 meters or more is installed, a combi boiler with a power of 35 kW is deemed sufficient.
When PPRC, namely polypropylene pipe systems, are used in the interior heating system, the insulation and insulation of the environment must be done well. PPRC pipe systems are generally preferred in central heating installations and are durable products that transmit heat with maximum efficiency.
Thanks to PPRC pipes that keep energy loss to a minimum, it is possible to heat a house with more radiators with a lower kW combi boiler. When choosing a combi boiler according to the radiator size, attention should be paid to whether the house is duplex or not.
Thanks to PPRC pipes that keep energy loss to a minimum, it is possible to heat a house with more radiators with a lower kW combi boiler. When choosing a combi boiler according to the radiator size, attention should be paid to whether the house is duplex or not.
Condensing Combi Boiler Advantages and Disadvantages
The features, advantages and disadvantages of condensing designs that attract the most attention during the combi boiler selection process are as follows:
● When considering the fuel consumption of combi boilers, condensing designs are the devices that offer the most energy efficiency.
● Condensing combi boilers offer equal performance to other models in terms of heating performance and heat efficiency, and they show their difference with low energy consumption.
● Condensing combi boilers, which have an environmentally friendly system, separate the hot water vapor in the gas they burn and include it in the heating system. Thus, it evaluates the hot water vapor obtained from the same gas more than once.
● The most important advantage of the condensing combi boiler is that it contributes to the environmentally friendly and renewable energy system.
The known disadvantages of condensing combi boilers are as follows:
● A disadvantage is that condensing combi boilers are sold at higher prices compared to conventional designs.
● A system similar to the waste water drainage of washing machines and dishwashers must also be prepared for condensing combi boilers.
● In cases where the waste water outlet is blocked, the operation of the condensing boiler is automatically stopped as a safety precaution.
● It is not suitable for central systems. While it is more efficient in single-storey houses, higher kW should be preferred in multi-storey flats.
Which Combi Boiler is Used for Underfloor Heating?
For the selection of underfloor heating combi boiler, it is necessary to prefer high-performance devices. In order to achieve high efficiency, it is more beneficial to combine the underfloor heating system with a condensing combi boiler. The underfloor heating system, which operates at low temperatures, provides energy savings in the long term with condensing and combi boilers with minimum operating options.
To get maximum efficiency from the system, it is sufficient to operate the combi boiler in the range of 35-40 degrees. Choosing condensing combi boilers that offer high efficiency at low temperatures and at the kW value appropriate for the square meter of the house increases performance.
Using the underfloor heating system, which is also compatible with conventional combi boilers, at very high temperatures will damage the parquet and floor material. When calculating the combi boiler suitable for underfloor heated spaces, care is taken to ensure that the device provides 80-100 watts of heat energy per square meter.
Combi Boiler Brands: Reliable Options
It is possible to find the most preferred among the reliable combi boiler brands in the list below:
● To faint
● ECA
● Buderus
● Bosch
● Vaillant
● Viessmann
● Protherm
● Dolce Vita
● DeDietrich
● Lambert
● Thermotechnics
● Warmhaus
The 2+ year warranty option, free installation and after-sales support services offered by the brands listed above highlight customer satisfaction. After installation, it is possible to get support from authorized service for any kind of malfunction and to provide original spare parts when necessary.
Combi Boiler Installation and After Sales Support
Eykom , the authorized dealer of popular combi brands, has after-sales support services. While the free installation of the combi of the preferred brand is carried out by the authorized service, it is also possible to receive support for any problems encountered during the usage process. In the problems encountered by users during the warranty period, free repair and renewal service is provided.
Combi boilers whose warranty has expired also have the opportunity to benefit from the services of authorized service within the scope of after-sales support. With the privilege of Eykom, you can find answers to all your questions about combi boiler selection via customer service and Whatsapp contact number. You can examine the campaign products in the online store and place an order immediately.
FAQ
▼ Which is the Most Preferred Combi Boiler?
Condensing combi boilers are the most frequently preferred high-performance and efficient designs.
▼ Which is the Quietest Boiler?
Condensing combi boilers are known as the quietest design with a sound power of 45 db(A).