When choosing a heating boiler, the consumer is faced with a very large amount of equipment that the modern market offers him, so making the optimal decision when purchasing becomes a painstaking and quite difficult task. Initially, it is necessary to proceed from an assessment of the possibility of the premises and the preferred method of heating the house.
The recommendation of most experts is to install a wall-mounted gas boiler with a closed combustion chamber, which now occupies the bulk of the presented models of gas heat generators and is used in private homes and in small industrial or public premises. Its qualitative advantages are compactness, efficiency, price feasibility and ease of maintenance.
Types of gas boilers
There is a division according to the type of combustion chambers of boilers. There are closed and open. Convection boilers can be of both types; condensing boilers are only of the closed type. You can read more about other economical heating boilers for a private home here.
Boilers with open combustion chamber
The open chamber is characterized by natural draft. In this case, air is taken from the room, and combustion products are removed through the chimney. In case of insufficient ventilation, there will be a constant lack of oxygen and there is a risk of combustion products getting inside. But these boilers have a lower price range.
It is advisable to install boilers with a closed chamber in a room with an equipped vertical chimney.
Boilers with a closed combustion chamber
Having a forced draft in its design, a gas boiler with a closed combustion chamber makes it possible to remove combustion products using an electric fan from the chamber through a coaxial chimney. The latter is one pipe located inside another. Air is sucked into the combustion chamber through the outer pipe and exhausted through the inner pipe. The usual location of such a boiler is vertical.
Wall and floor boilers
Based on the design options, there are floor-standing and wall-mounted boilers. The type of wall-mounted boilers has the advantage of a more compact location, taking up little space, which makes them suitable even in city apartments. When installing a gas floor-standing boiler with a closed combustion chamber, you need to remember that a separate room may be required. But they have more power and are equipped with cast iron heat exchangers. Further, gas boilers for heating a house can be double-circuit or single-circuit.
Single-circuit gas boilers
The task performed by single-circuit gas boilers with a closed combustion chamber is to provide heating. Double-circuit units simultaneously perform the heating function and also produce sanitary hot water. Often used single-circuit gas heating boilers have a method of heating the coolant in a heat exchanger and its further entry into the heating system, where heat is released and the room is heated.
Double-circuit gas boilers
A double-circuit boiler, being an effective heating device, has a slightly different structure. It is used when it is necessary to solve the problem of the need for hot water and to ensure a sufficient level of heating. The choice of most consumers remains with wall-mounted gas double-circuit boilers with a closed combustion chamber. Connection, installation and further use will not require much effort and time.
Construction of gas boilers with a closed combustion chamber
Gas combustion in installations with a closed chamber occurs due to the forced supply of air to the burner zone. An electric fan is provided for this purpose. The heating block consists of a chamber, inside of which a nozzle is installed and an air channel is supplied to ensure the combustion reaction. Water is supplied between the double walls of the working chamber, acting as a coolant.
The gas enters through the nozzle into the chamber, where it is completely burned to form carbon dioxide and water vapor. Waste products under pressure provided by the supercharger are discharged through a channel and then released into the atmosphere. The water is heated in a heat exchanger located in the combustion chamber and then enters the heating system.
A coaxial chimney is used to supply air and exhaust smoke. It is a “pipe-in-pipe” design. Smoke is removed through an internal channel of smaller diameter (a separate channel is not needed for it). The fresh air entering through the outer ring is heated by the heat of the exhaust gases. The continuous flow of the latter is ensured by an electric fan.
This design makes it possible to achieve almost complete combustion of fuel, so the efficiency of such installations is higher than that of atmospheric combustion devices. This means that the water contact area is larger, so the heat exchange process is more efficient.
Since an electric fan or turbine is used to supply air, these installations are often called turbocharged boilers.
Features of a gas boiler with a closed combustion chamber
The main difference between boilers with open and closed combustion chambers on the market lies in the way they absorb oxygen as a design feature. In order to heat a living space, it would be more correct to choose a gas boiler whose closed combustion chamber will provide better applicability for the home.
The option of purchasing an open form is best used in boiler rooms. The open chamber works on the principle of absorbing oxygen from the air in the room. At the same time, care must be taken to constantly ventilate it to avoid lack of air.
During the operation of a closed combustion chamber, the air that ensures its normal functioning is absorbed through an installed coaxial chimney from the street. Then the products processed by this chamber are also taken out into the street. This allows you to do without additional ventilation structures.
The combustion chamber is located separately from the room with the heat generator. This leads to the fact that the leakage of gas or combustion products becomes impossible, since no air is taken from the house. If the gas pipeline is tight and there is no damage to the combustion chamber, the possibility of an accident will be excluded. Air intake and removal are forced; a boiler fan is used.
Boilers with a closed combustion chamber are often called turbocharged. Technologically, the coaxial pipe and separate channels can be routed horizontally, eliminating the need for a vertical chimney.
Gas boilers with a closed combustion chamber
Boilers with a closed chamber are more technologically advanced and complex, so their cost is often higher than that of boilers with an open chamber. Combustion of gas fuel occurs in an isolated closed chamber; air is pumped in and combustion products are removed using a fan (turbine). The gas combustion process is regulated automatically, which allows optimizing fuel consumption.
Air intake and smoke exhaust can be done either through a separate or through a coaxial chimney (side, through the wall). It is designed according to the “pipe-in-pipe” principle. This option is the safest to use. Air is not taken from the room, so boilers with a closed chamber can be installed in the kitchen or other suitable room.
Obvious advantages of boilers with a closed chamber:
- higher efficiency indicators (efficiency, environmental friendliness, safety) in comparison with atmospheric models;
- a coaxial chimney is easier to install than a classic one;
- stability of traction without the risk of being blown by the wind;
- there are no strict ventilation requirements;
- can be installed not only in the boiler room, but also in other suitable rooms.
The disadvantages include:
- higher cost (10-30% more expensive than atmospheric);
- energy dependence;
- higher gas consumption when operating at partial power compared to an open chamber;
- the risk of chimney icing, however, you can buy a special coaxial chimney with anti-icing protection;
- slightly increased noise level from the operation of the turbine (fan), but this is almost imperceptible.
The best boilers with a closed combustion chamber in 2021
- Vaillant turboFIT VUW 242/5-2, 24 kW
- Vaillant turboTEC pro VUW INT 242/5-3
- Vaillant ecoVIT VKK 286/4
- Protherm Cheetah 23 MTV
- Protherm Jaguar 24 JTV
- Protherm Lynx K 25 MKO
- BAXI ECO Nova 18 F
- BAXI ECO Nova 24 F
- BAXI LUNA-3 240 Fi
- BAXI SLIM 1.300 FiN 5E
Advantages of using gas boilers with a closed combustion chamber
A gas floor-standing boiler with a closed combustion chamber has undoubted advantages; the main ones should be highlighted. When the waste material is released, all gas products are cooled. This makes the use of such boilers safe. The room in which such a device is used warms up without the formation of various air pollutants; combustion processes occur outside the premises or home, on the street. Therefore, the use of gas boilers is comfortable.
The efficiency of a gas boiler is quite high. This is due to the fact that the air entering the pipe is warmed up. As a result, boilers with a closed combustion chamber have environmentally friendly qualities. The gas in them is burned better with a significant reduction in emissions into nature.
Along with this, it should be noted that such equipment will not be able to operate without electricity - in this case, the heat generator will turn off and the operation of the fan will stop. When electricity appears, the boiler starts automatically.
Boilers with a closed combustion chamber
The design of such a device is the most productive, since the gas entering it is burned out almost completely. The smoke has less toxic properties, in contrast to the type of combustion chamber discussed above. The presence of a chimney is not necessary for it.
Principle of operation
The operation of gas boilers with a closed combustion chamber occurs due to the fact that air is forced into the area where combustion occurs. The design of the heating block has undergone some changes, and is a chamber, inside of which there is a nozzle and a channel for supplying air from an external fan. There is water between the double walls. When the gas burns, it is heated, and the smoke escapes through the chimney under the pressure created by the blower over long distances. Short chimneys are often used to vent smoke outside. In such cases, they are installed horizontally. Air enters the boiler in the same way as the water is removed. Due to the double walls of the chimney, the intake air is heated by the heat of the exhaust.
Advantages and disadvantages
A number of advantages of boilers with this type of combustion chamber include:
- minimum fuel consumption when compared with the consumption of open burners;
- if the turbine is in working condition, the draft and stability of the boiler are guaranteed;
- suitable for installation in multi-storey buildings, since there is no need to construct a chimney. Smoke is released under pressure over a distance of more than three meters;
- does not require the creation of a separate room or provision of continuous ventilation. The gas mixture is prepared together with outside air.
In addition to its advantages, any complex unit can always have a number of disadvantages that will help you make the right choice:
- Boilers with this type of combustion chamber require maintenance quite often. When checking, you should always pay attention to the condition of the turbine, clean the blades and lubricate them.
- The turbine has a limited lifespan. This is typical for all units that have moving parts.
- The combustion area may freeze. This happens because the chimney is too short and in bad weather conditions such as wind and frost it can lead to an accident. Models that are produced nowadays are equipped with additional parts in the form of plugs that respond to external temperature. Such structures are more prone to failure.
- The noise from the boiler is at a fairly high level, it is created by a working turbine. Over time, the bushings wear out and the blades become dirty, which further increases the noise.
- Although fuel consumption is economical, the same cannot be said about electricity. The turbine and electronic control system require a large amount of electricity.
Popular brands of gas boilers
Installation of wall-mounted gas boilers occurs everywhere. They are widely used for heating apartments, houses, cottages and dachas. The boilers are supplied for connection with maximum comfort and minimum installation. They are compact and have a modern design.
Wall-mounted gas boiler Wolf CGG 1K 24
The wall-mounted gas boiler Wolf CGG 1K 24, designed for flow-through hot water supply and heating, is characterized by high efficiency and can be installed in a wide variety of facilities. The boiler is perfectly adapted to work in difficult conditions, taking into account the instability of gas pressure, and guarantees an effective solution to the problems of heating and hot water supply.
Among its advantages are reliable and stable operation even during power surges or gas pressure changes. It has a robust design and is easy to install. Thoughtful functionality allows the installed gas fittings to select the optimal mode and save gas consumption. The boiler components have undergone strict control.
