Open combustion chamber in a gas boiler. Chimney of closed combustion chamber

In the process of purchasing gas burner equipment for heating and domestic hot water, each potential buyer is faced with the fact that one has to choose from a variety of models that differ from each other in a huge number of parameters. Depending on the priorities that we set in the process of choosing a heating boiler, it is possible to choose the optimal engineering solution for a particular house or apartment, taking into account the climatic specifics of the region and the characteristics of the room.

All such equipment can be divided into two large groups - units with an open and closed combustion chamber. Each type of structure has its own characteristics, advantages and disadvantages. It is this question that we will consider in as much detail as possible below.

What is the "trick" of boilers with a closed combustion chamber?

Gas burner equipment equipped with a combustion chamber of this type is a practical and very convenient technique in daily operation. By purchasing such a design, you give up a lot of problems and inconveniences that you might encounter if you give preference to open-type units.

Boilers with a closed combustion chamber save living space in the house, since they do not require the arrangement of a separate room for a boiler room. You can install such a device absolutely anywhere, including in the kitchen or in the bathroom. In this case, of course, the room must meet certain requirements. These boilers are ideal for private apartments and small houses in which the issue of space saving is very relevant. It is enough to choose a place with an area of ​​​​several square meters for the installation of the boiler, and your home will be constantly supplied with hot water.

Of course, if you purchase such a gas boiler, the closed chamber must receive fresh air from somewhere and somehow bring the exhaust gases out. It would seem that the arrangement of the chimney is not an easy task. However, this is only at first glance. In fact, such boilers do not need to be equipped with a vertical chimney.

For the normal and safe operation of such equipment, horizontal smoke removal by means of a coaxial design is sufficient. For more efficient removal of exhaust gases, the unit is equipped with a powerful cooler, which simultaneously provides fresh air into the system and remove the smoke. Naturally, the presence of a ventilation element that functions from electricity imposes certain restrictions on the scope of the boiler.

In those regions where power is often turned off for a variety of reasons, the installation of such equipment can lead to unstable operation of the system. Of course, in the cold season, such a problem can turn a dwelling into an “ice hut”. Dependence on electricity is one of the undoubted disadvantages of technology with a closed combustion chamber.

The fact that such boilers take air from the street speaks of their more high efficiency compared to similar models equipped with open fireboxes. More efficient combustion of fuel allows you to save a considerable amount throughout the entire heating season which will be appreciated by practical buyers.

For the full functioning of a closed-type boiler in a house or apartment, it is necessary to install a coaxial chimney, which is a “pipe in pipe” type structure. Fresh air is drawn into the system through a larger diameter tube, and exhaust gases are expelled through a small one.

A coaxial chimney is a rational and very convenient engineering solution that does not require the installation of additional ventilation. This design has a number of advantages, including:

• High level of security. The exhaust gas passes through the tube, which is cooled from all sides by a stream of fresh air. Passing through the coaxial element, the smoke cools down.
• Environmental safety of equipment. Raise System efficiency is carried out due to the coaxial chimney, which contributes to more efficient combustion of fuel in the boiler.
• User comfort. Since the system is completely isolated from the room in which the gas boiler is located, the combustion air is not taken from the room. In turn, combustion products also do not enter the house or apartment in any way, since they are effectively removed through the horizontal chimney to the outside.

It should be borne in mind that a floor-standing boiler with a closed combustion chamber is more expensive than its open-type counterpart. Perhaps this is one of the few shortcomings of this equipment. However, considering all the advantages described above, one can easily come to the conclusion that buying a unit with an insulated firebox is a practical and economically sound decision. To verify this, let's take a closer look at designs with an open chamber.

Pros and cons of gas boilers with an open combustion chamber

Natural draft units are classic heating equipment that draws combustion air directly from the room in which it is located. At the same time, the equipment must necessarily be aggregated with a full-fledged vertical chimney. Otherwise, it will not meet the safety requirements.

One of the obvious disadvantages of technology with an open combustion chamber is the intake of fresh air from the living quarters. The room where the equipment is located is often very stuffy and there is a lack of oxygen. There are also confirmed cases of carbon monoxide poisoning in apartments where such appliances are installed. For this reason, buying a unit of this type, it is worth taking care of the availability of high-quality ventilation.

The ideal solution is the installation of equipment in a specially designated room allocated for a furnace. In this case, you will be able to avoid the discomfort that an open-type boiler entails.

Despite the complexity of installation and the specifics of operation, such equipment has several advantages. The first one is more low price compared to closed devices. The second advantage is independence from the supply of electricity, since the exhaust gases are discharged naturally, and not with the help of a fan. Thus, an open-type gas boiler is suitable for country houses located in regions where there are problems with the supply of electricity.

Summing up

From all of the above, a number of conclusions can be drawn:

• Boilers with a closed combustion chamber are characterized by high performance due to a more efficient intake of fresh air for fuel combustion.
• For the full-fledged stable operation of a unit with a closed chamber, it is important to have a coaxial chimney, which is easily equipped in the wall of a private or multi-storey building.
• Equipment with a closed firebox is noisier than its open counterparts.
• Boilers with a closed chamber are volatile, which excludes the possibility of their installation in the "problem" regions of Russia, where there are often interruptions in the supply of electricity.

With this information in hand, you can easily select the best gas burner equipment for your home. We have considered all the pros and cons of boilers with a closed and open combustion chamber. Understanding the pros and cons, you can easily navigate the wide variety of models on the market.

The boiler is the central element of any heating system, and if you want to purchase a high-quality gas double-circuit wall-mounted boiler, then you can assume that you have come to the right place. The Tavago company will offer you the best gas boilers from the world's leading manufacturers. Only the best prices, only positive reviews and huge selection already waiting for you in our catalog!

What is a gas double-circuit wall-mounted boiler?

Such boilers are gas-based heating devices. gaseous fuel is burned in such a boiler, as a result of which a certain amount of thermal energy is generated. This energy can be used for space heating, water heating, etc. Most often, natural gas is used as the initial fuel for gas boilers - propane-butane and methane. And there are several reasons to choose just such a gas:

Ease of use;

The ability to quickly automate the operation of gas-powered devices;

Profitability of gas consumption;

Fuel availability;

High level of gas combustion efficiency and, as a result, sufficient heat to heat residential and industrial premises.

Working principle and main advantages

Double-circuit gas boiler operates on simple principle. First, gas is supplied to the device, after which the ignition is turned on in it. After creating a spark, the igniter is ignited, which, in turn, ignites the burner. The burner heats the coolant in the system until the set temperature level is reached. The temperature is set on the thermostat, so that when the desired level is reached, the system stops. In the same case, if the temperature drops below the set mark, the boiler will turn on automatically and start the heating process to the desired temperature.

Wall construction The boiler allows you to install it directly on the wall, or in a special niche in it. This arrangement makes it possible to save space and provide convenient access to the boiler and its main controls and regulation. A double-circuit boiler heats not only the coolant in the heating system, but also the water supplied for domestic and economic needs. In this case, you do not need to connect any additional equipment.

Gas boilers can vary according to the principle of ignition. So, depending on this moment, they are divided into two large groups:

Models with electric ignition. Works automatically;

Models with piezo ignition. To turn it on, press the corresponding button.

The type of ignition does not affect the performance of the boiler. This is purely a matter of ease of use. You just need to understand that electric ignition leaves a small price imprint on the boiler, slightly increasing its cost.

Purchase of a gas boiler

Double-circuit gas boilers are very durable devices in use. Typically, the life of the boiler under normal conditions and careful attitude reaches several tens of years. In order to ensure maximum performance for the heating system, and at the same time not to overpay for specific model and its further operation, you should carefully approach the selection process. First of all, it is necessary to correctly calculate the required power. A Tavago consultant will be able to help you with the calculations if you apply accordingly. With it, you can quickly calculate a number of key indicators:

Type and number of heating radiators;

volumes of heat loss;

Approximate power of the heating system;

Maximum and minimum heating temperature;

The final cost of the boiler, etc.

With our help, you will be able to choose the best boiler for providing heating and continuous heating of water. We will present to your attention a number of unique models of gas boilers that are ideal for the implementation of your tasks. Hurry up to evaluate the favorable conditions of purchase and enjoy the excellent quality and power of the models we offer!

The desire of many apartment owners to achieve maximum autonomy, independence from city utilities is quite understandable. One of the main issues in this regard is the creation of our own heating system. This allows you to independently determine the start and end dates of your “local heating season”, setting the desired temperature in the premises at any time of the year, without freezing if the cold in autumn came too early or the arrival of spring was too long, and without suffering from the heat if the situation develops in a diametrically opposite way. And from the point of view of payment for services, it turns out to be much more profitable. Therefore, the installation of individual heating boilers becomes among landlordin in an increasingly popular trend.

Well, if the owners plan to create their own autonomous heating system, then it would be quite reasonable in parallel with this to immediately resolve the issue of independent hot water supply. It's no secret that almost everywhere with the supply hot water various “surprises” happen throughout the year, and in addition, prices for public Utilities tend to grow steadily. In this way? own heating and hot water supply system is not only “technical”, but also, to a certain extent, financial independence. In addition, an important aspect is.

Of course, the conditions of apartments in multi-storey buildings, which are cramped in area, limit the owners in choosing boiler equipment. However, there is a way out - this is a gas double-circuit wall-mounted boiler, how to choose which will be discussed in this publication.

The principle of operation of double-circuit boilers

Currently in cities network gas remains the most inexpensive source of energy. If multi-storey building connected to a gas main, then for sure, despite certain administrative and technological difficulties in installing the corresponding equipment, such a heating and hot water supply system will be the most profitable. Paying bills only for real spending "blue fuel", the hosts receive in return and independent heating, and uninterrupted supply of hot water for household household needs. And and the timing of inclusion, and the heating temperature - it all depends on the desire of the owners of the apartment.

With a certain simplification, the principle of connecting a double-circuit boiler can be schematically depicted as follows:

The boiler itself (pos. 1) is placed on the wall in the most convenient place, where it will be connected to the gas main (pos. 2) and to the combustion products removal system.

Hot water circuit. A cold water supply pipe is connected to the boiler (item 3, blue arrows). Heated water is distributed (pos. 4, red arrows) through a collector or corner circuit to points of consumption - in a bath (pos. 5), a shower stall (pos. 6), a kitchen sink (pos. 7), etc.

The heating circuit is closed. Circulation pump (most often it is constructive node boiler itself) ensures the movement of the coolant through the supply pipes (pos. 8) and "return" (pos. 9). Depending on the specific features of the heating system, ordinary radiators (pos. 10), water heated floors (pos. 11), convectors of one type or another (pos. 12) can be connected to the heating circuit. If desired, other devices can also be inserted here, for example, heated towel rails (pos. 13).

Thus, five pipes fit and connect to the wall-mounted double-circuit boiler:

• Gas main.
• Supply of the heating circuit with further distribution to priors or heat exchange systems.
• "Return" of the heating circuit.
• Cold water inlet
• Outlet of the heated water pipeline for household needs with subsequent distribution to water intake points.

Inside the boiler itself, both circuits - heating and hot water supply do not directly intersect, which makes it possible, if desired or if necessary, to use a special coolant in the heating.

By and large, this is the fundamental difference with single-circuit boilers, many of which have the ability to connect to a hot water supply system, but only through an indirect heating boiler.

Look at the diagram. Everything seems to be the same, but the points of consumption are hot household water connected to an indirect heating boiler. And already he, in turn, connects to the dedicated the contour of the boiler, along which the same coolant circulates as in the heating system.

Even if such a boiler has four water pipes at the outlet - two for heating circuits, and two for an indirect heating boiler, it will still not be considered a double-circuit one. It's just that its internal design provides for a rational redistribution of coolant flows with the necessary automation of this process. But the heat exchanger is used alone, and the composition of the liquid circulating in both circuits is no different.

A system using an indirect heating boiler has a number of significant benefits. In particular, it is possible to organize local closed DHW recirculation - at any time, whenever the tap is open, hot water will immediately flow from it set temperature.

But there are also a few negatives. Firstly, the cost of such a kit is always quite high. And second, for small apartments, perhaps, the main thing is that the installation of a boiler and a boiler will require a considerable area, which is far from always possible.

It is in such conditions that a double-circuit wall-mounted boiler will help out. Its main advantages:

• Compactness - it does not take up much space, and at the same time, as a rule, it does not harmonize with the kitchen interior.

• Two tasks are solved at once - heating the apartment and meeting the needs for hot water. The owners largely get rid of the "whims" of utilities.
• Similar boilers for correct installation and a well-thought-out, balanced autonomous heating system are very economical - this will certainly be immediately noticeable in the amount of monthly utility costs.
• The total costs for the purchase and installation of a double-circuit boiler will be significantly lower than for a single-circuit boiler with an indirect heating boiler.

However, double-circuit boilers and significant shortcomings:

• These devices operate simultaneously in only one mode. For example, if it is necessary to heat domestic water, the boiler switches completely to water supply, temporarily turning off the heating circuit.
• As in the case of a gas water heater, there is a certain “inertia” - when you open the tap, you will have to wait until the cold water remaining in the pipes flows out and until the boiler “accelerates” to the desired heating temperature.
• Many double-circuit boilers are very limited in terms of heating running water. So, taking a shower and washing dishes at the same time will either not always be possible, or uncomfortable - when you close one tap in another, a temperature jump will inevitably occur. True, many modern appliances equipped with an internal boiler, which eliminates this disadvantage.

• If in a single-circuit boiler the purity of the coolant can be achieved, then in a double-circuit Besides tap water is heated, which does not always and everywhere differ in quality. This poses a certain risk of overgrowth. heat exchanger tubes will either need to be cleaned regularly or replaced with new ones.

Which double-circuit wall-mounted boiler to choose?

The boiler connection diagram shown above is very arbitrary, and in no way covers the variety of these devices. So in order to correctly determine the desired model, it is necessary to take a closer look at the main selection criteria.

Boiler power and performance

• The boiler must fully cope with its main task - to ensure the operation of an autonomous heating system. Hence, one of the basic selection criteria is its thermal power.

Specialists calculate the need for an apartment or house in the total amount of heat, based on many factors - from the area and volume of the premises to the material of the walls, the degree of insulation of the building and climate zone residence. To independently determine the required power of the boiler, it is possible, with acceptable simplification, to proceed from the standard of 10 m² of the area of ​​\u200b\u200bheated rooms per 1 kW. this rule will be valid with an average ceiling height of up to 2.5 - 3 m, and in the event that the rules for proper thermal insulation are still observed in the house (apartment).

It is clear that the heater should not work at the peak of its capabilities, so it is better to lay a certain margin, especially in the case when the insulation of a high-rise building still does not cause complete confidence. Plus, the boiler needs additional power to work on heating water. In a word, it will not be a mistake to add another 30 ÷ 35% to the obtained value.

Most modern double-circuit boilers have a fairly wide power range. The technical documentation usually indicates its minimum and maximum value. For example, useful heat output: 9.3 ÷ 14 kW.

• The second component of the problem is the performance of the device for heating water for domestic needs. If there is no boiler, then the heating will be carried out according to the flow scheme, and the selection parameter depends on the number of draw-off pointsthat can work simultaneously. It is clear that the more liters per minute the boiler can heat up, the better.

Usually, in the technical documentation of double-circuit boilers, several performance values ​​\u200b\u200bare indicated, with different indicators of the difference in temperature at the inlet and outlet. Usually operate with values ​​Δt° = 25 and 35 degrees. This is not the outlet water temperature, but the rise in its value compared to the inlet. For example, in the summer, water in the water supply can have 15 ° FROM, and at Δt° = 25°, 40° will flow into the taps, which is quite enough for taking a shower.

In principle, a performance of about 10 ÷ 11 l/min at Δt° = 25 ° FROM, and 7 ÷ 8 l/min at Δt° = 35 °C.

All these considered characteristics will be valid only if the gas pressure in the pipeline and water in the water supply system correspond to the parameters specified by the manufacturer. This should also be taken into account close attention.

Type and number of heat exchangers

According to the principle of heating water for hot water, boilers can vary significantly. So, there are two main varieties of such devices - with a secondary heat exchanger and with bithermic. Each type has its own characteristics.

Main boiler heat exchanger is responsible for the most energy-intensive function, heating, always located above the gas burners. And water heating can take place in the same place, or with heat transfer from a heated coolant through an additional device - a secondary heat exchanger.

Double-circuit boilers with a secondary heat exchanger

The primary heat exchanger itself is metal structure- a curved pipe, the coils of which are united by lamellar ribs to increase the heat exchange area from the hot combustion products to the circulating coolant. In this version of the boiler, such a heat exchanger has two pipes - inlet and outlet.

Heating of water for domestic needs is carried out in a secondary heat exchanger, which is located below the combustion chamber and does not come into contact with the burner flame in any way. Typically, this element has a compact plate design.

Secondary heat exchanger - more compact, plate type

Here there are already four pipes, and inside there are two contours of the oncoming movement of the liquid. On one - the heated coolant circulates, giving off heat, on the second - tap water receiving it.

The principle of operation of such a boiler is shown in more detail in the diagrams.

• The boiler is in heating mode.

Above the gas burner (pos. 1) is the primary heat exchanger (pos. 3). The combustion of the gas flowing through the main (yellow arrow) leads to heating of the coolant in the circuit. The circulation pump (pos. 5) ensures the movement of fluid through the heating pipes. At the same time, the three-way valve with a servo drive (pos. 7) is in a position in which the valves open the flow from the return of the heating circuit and at the same time block the inlet to the secondary heat exchanger.

Prices for Baxi gas boilers

gas boiler Baxi

As a result, the circulation goes "in a big circle", through the heating collectors and installed heating devices.

The diagram additionally shows the built-in expansion tank (pos. 8) and the safety group - safety valve and automatic air vent(pos. 9).

• What happens when you open a hot water tap?

Water flows through the pipes of the DHW circuit. This causes the impeller of the flow sensor (pos.6) to rotate. The signal from the sensor enters the automation unit, where a control pulse is generated on a three-way valve (pos. 7). Move the valve to the position in which the valve closes the inlet from return lines heating, but opens the entrance to the secondary heat exchanger. At the same time, the pump does not turn off, providing circulation of the heated coolant in a "small circle".

During the use of hot water, the circulation of the coolant through the heating circuit is suspended.

In the event that this happens during a period when the heating is turned off altogether, when the hot water tap is turned on, the flow sensor will send a signal to the control unit, which will start circulation pump, will open gas valve and trigger the electronic igniter (pos. 2). The gas heaters (pos. 3) are ignited, and the circulation of the coolant through the secondary heat exchanger begins with the transfer of thermal energy to the water.

Advantages of boilers with a secondary heat exchanger:

• Dual heat exchange eliminates the possibility of getting burned from excessively hot water. Under any circumstances, if the temperature in the primary circuit can reach 80 ° FROM, then in the secondary it will not rise above 60.
• For the same reason, and also because heating occurs exclusively when circulating in both circuits at the same time, scale build-up in the secondary heat exchanger is much less than in boilers with a bithermal heat exchanger.
• The tubes of the primary heat exchanger can be made thicker, and they will be less at risk of clogging or fouling.
• Even an overgrown primary heat exchanger can be washed and cleaned.
• This boiler is more maintainable- each node can be removed, cleaned or even replaced. The cost of each heat exchanger separately- not so high.

Disadvantages of boilers with secondary heat exchange in the DHW circuit

• The price of such equipment is higher than with a bithermal heat exchanger.
• The presence of an additional electromechanical valve ( three-way valve) is an extra vulnerable spot for breakage.

Video: a small "lecture" on the installation of a wall-mounted double-circuit boiler

Boilers with bithermal heat exchanger

In these types of boilers, both heat exchange circuits are combined into one structural unit.

Bithermal heat exchanger - outside view ...

Externally, the heat exchanger seems to be similar to the primary one, which was already mentioned above. But there are already four branch pipes - a pair for heating and hot water.

... and he is in the context

If you look at the section of such a heat exchanger, you can see that the tubes have a cellular structure. Hot water is circulated through the central channel. External channels (in this case - four) are designed to circulate the coolant of the heating system.

If only heating is turned on, then the circulation pump ensures the movement of the coolant, and the water in the central channel is stationary.

When a hot tap on the mixer is opened, under the action of the pressure of the water pipe, the movement of water through the inlet pipe (pos. 1) towards the outlet (pos. 2). The flow sensor through the control unit turns off the circulation pump of the heating system, and the movement of the coolant stops. Heating from the burners is taken over by the heated water. When the tap is turned off, the pump resumes operation, and the heating system becomes the main one.

Advantages of such a scheme:

• One heat exchanger takes much less space. In addition, there is no servo-driven t-way valve, additional piping. This makes the whole structure of a double-circuit boiler much lighter and more compact.
• Although a bithermal heat exchanger is enough complex from the point of view of the manufacturing technology of the part, its cost is still lower than two separate heat exchangers. This also affects the price of the boiler.

The disadvantages are very significant:

• In any mode, in one of the heat exchanger circuits, the liquid is stationary, but is heated. This leads to a fairly rapid formation of scale and overgrowth of the channels.
• The relatively narrow lumen of all channels also leads to the same consequences. Overgrowing of at least one of them entails a decrease in the characteristics of the boiler and the appearance of unpleasant noises.
• While the hot water circuit is closed, the water continues to heat up and reaches the same temperatures as the heating medium. When the faucet is turned on, very hot water may initially flow, which can scald the skin. To minimize such a risk, they try to limit the total heating temperature by hardware and software methods (not higher than 70 ÷ 75 ° FROM, although this is too much). But such a decrease at the same time entails a decrease in the possible thermal output of the boiler for the heating system.
• A bithermic heat exchanger is more difficult to manufacture, and the presence a large number joints greatly increases the likelihood of leaks. Rinsing such a design from scale is much more difficult. Well, in the event of a leak (especially between the external and internal circuits), such a heat exchanger is practically beyond repair and requires mandatory replacement. But its cost is much higher than both primary and secondary in boilers of a different type.

Thus, according to these positions, a boiler with secondary heat exchange in the hot water circuit still looks preferable.

Vaillant gas boiler prices

gas boiler Vaillant

There is another innovative type of double-circuit boilers - with a condensing type primary heat exchanger. They are designed with an eye to a rather serious effect of saving gas consumption at the same or even more high rates thermal power.

The fact is that one of the combustion products of natural gas is always water vapor. He is in conventional boilers is simply thrown into the atmosphere, but meanwhile it thermal energy(temperature reaches 110 - 140 ° FROM) can be additionally used to heat the coolant.

The special device of the heat exchanger ensures the condensation of steam with heat transfer. Studies have shown that steam potentially stores up to 11% of the total heat produced by the boiler, and if their unreasonable losses are returned to heat exchange, then gas savings per season can reach 30% of the usual level of consumption.

Undoubtedly, such energy-saving boilers are the future, and in many countries they have taken a leading position in popularity. The only thing that keeps them widespread in our area so far is a very high price.

Type of combustion products removal system

Boilers are divided into two large subgroups - with an open combustion chamber and with a closed one. Accordingly, they are also poured into the systems for supplying the air necessary for combustion of the gas and removing the combustion products into the atmosphere.

Chimney boilers with an open combustion chamber

An open combustion chamber assumes that the air supply to the burners occurs naturally, from the room in which the boiler is located. Combustion products, also naturally rising up, are redirected to the branch pipe to which the chimney is connected. In a word, the effect of natural draft is used, based on the difference in the density of cold and heated gases.

The advantages of such a boiler:

• Operation does not require a special fan. This is both the absence of noise and the lower power consumption of the boiler.
• In contraction there are no complex elements of air injection and control (pneumatic relay), therefore, the overall reliability of the device is higher.
• A chimney assembled according to all the rules solves the problem with the formation of condensate.
• Chimney boilers are cheaper than turbocharged ones.

Disadvantages:

• Air enters the combustion chamber directly from the room. So, you should consider the issues of constant supply ventilation. And this very often leads to excessive heat loss in the premises, to the appearance of drafts.
• There are special, rather strict rules for the design and installation of a chimney. This often leads to large-scale repair and construction work and serious expenses - otherwise you will not get permission to install the boiler.
• Not in all buildings, the installation of a chimney is possible in principle.

Smokeless boilers with a closed combustion chamber.

Such boilers are still very often called turbocharged. The air for them is forcibly supplied from the street, using a special fan-turbine, respectively, and the products of combustion are thrown out onto the street by the created pressure.

The chamber itself is completely closed, and the entry of exhaust gases into the room is excluded.

Air supply and exhaust of combustion products can be carried out through two separate pipes, but in the vast majority of modern boilers of this type, an installation is provided coaxial system- "pipe in a pipe", which is displayed through the wall to the outside.

Inside the outer tube with a diameter, as a rule, 100 mm, a second one, with a diameter of 60 mm, is coaxially located. Through the space between the outer wall and the inner pipe, forced air is taken from the street. The internal channel serves for the exit of combustion products.

The advantages of such a system:

• There are practically no significant restrictions on its installation.
• In the room there is no need to provide supply ventilation.
• The cost of such boilers is slightly higher, but it is fully justified by the lack of large-scale work on the design and construction of the chimney.

The disadvantages are the following:

• Significant temperature difference in the external and inner tube accompanied by condensation. In severe frosts, this can lead to icing with a violation of the patency of the chimney and, accordingly, insufficient vacuum in the chamber to trigger the automation.
• Mandatory elements systems - pneumatic relay, fan and fan switch relay. All of them have a certain resource, and the failure of any of them leads to the failure of the boiler.
• The fan makes noise during operation. In addition, it is an additional power consumption.

Conclusion: a boiler with an open combustion chamber and a conventional chimney looks more reliable in operation. But turbocharged boilers are easier to install and do not have any special restrictions on the installation site.

You might be interested in information on how to choose

Controls, automation, protection levels

The boiler must be fairly easy to use, have clear controls, be equipped with the necessary functions to optimize operation and several degrees of protection against emergencies.

Leading manufacturing firms they are constantly improving their models, thereby creating competition between brands, so new and new developments are constantly appearing. So, modern boilers can be equipped with the following options:

• Modulation of a flame in the modes of heating and heating of water. The flame level is electronically regulated, providing smooth starts, which is especially important for models with instantaneous DHW heating. Automation independently selects the height of the flames depending on the set temperature and the specific current water flow.

In some models, the last 5 degrees to the set heating temperature of the heating system are gained at a reduced combustion intensity. This allows you to make the operation of the device smoother, reduce the number of starts, and therefore - and increase the service life of the equipment.

• Similar goals are pursued by the smooth electronic ignition system, when, after the appearance of a minimum flame on the burners, it gradually grows to given intensity burning for 30 - 40 seconds.

When the boiler is operating as a water heater, this option is not used - here, on the contrary, the rate of heating water to a predetermined level is important.

• weather dependent boiler automation. This innovation, when installing an external outdoor sensor, allows the equipment to monitor the level of the external temperature and make adjustments to maintain the optimal microclimate in the apartment.

More advanced equipment of this type also has the function of automatic self-adaptation. Electronics not only compares graphs of changes in external and internal temperatures, but also conducts an analysis, making adjustments to the operation of the boiler, which leads to both maximum comfort and significant gas savings.

• Pump post circulation. Useful feature, which, with the established room thermostat, can significantly reduce energy consumption. After the required heating temperature has been reached in the heating system, the boiler is switched off and the pump continues to operate for another three minutes. The start of both the boiler and the pump, if necessary, the resumption of work is carried out simultaneously.
• Naturally, all modern electronically controlled boilers allow you to accurately set the temperature in both the heating circuit and the hot water supply. In addition, some models have two switchable ranges in heating mode - for conventional radiators and for underfloor heating.
• Electronics allows programming the operation of the boiler for a certain period, with the entry of programs into memory for reuse.
• Any gas equipment has several degrees of protection - in case of insufficient traction, when the heating pad is attenuated, in the absence or insufficiency of water pressure in the circuits, etc. In addition, modern models are equipped with other safety features. So, if the temperature in the circuits drops to +5 degrees, the boiler will start up on its own to bring the level of heating of the coolant and water to a safe value, in order to avoid freezing. In addition, some control systems monitor the condition of the boiler elements. If the device has not been used for more than a day, the processor will turn on pump or switch back and forth the position of the three-way valve. This avoids blocking or "sticking" of these nodes, prolongs their service life.

Control panels can have push-button, touch or electromechanical control, are supplied with pointer or digital indicators of temperature and pressure in the system.

Prices for popular gas boilers

Dimensions, "appearance", manufacturing company

A mandatory evaluation criterion should be the dimensions of the boiler - they must correspond to the dimensions of the place where it is planned to be installed. This takes into account the location of the gas line, and the possibility of connecting to a chimney or installing a coaxial system. There are certain restrictions in these matters, for example, along the length of the coaxial pipe - this must be clarified in the product passport.

You might be interested in information on how to choose

Perhaps, if the area of ​​​​the installation site allows, it makes sense to purchase a boiler with built-in boilers - it certainly has larger dimensions, but also ease of use is incomparably higher - this has already been mentioned.

For many hosts important criterion choice is the design of the boiler. It is difficult to give advice here - the main thing is that the device does not spoil the interior. Most of the cauldrons have a matte white finish that goes well with any style.

No matter how much you like this or that model presented for sale, you should always give preference to reputable brands. Leading manufacturing companies give a solid guarantee for their equipment, and since the boiler can be attributed to an expensive purchase, this fact has a very importance.

Very popular modern model"Baxi - Luna3"

well-deserved authority and untarnished reputation"Used by European companies Viessmann, Beretta, Baxi, Vaillant, Bosch,. Protherm, Buderus, Ariston and other firms have proven themselves well. It is quite possible to trust the products of the Korean companies "Navien", "Daewoo", "Celtic", "Kiturami" - in terms of equipment with modern electronics, they sometimes surpass Europeans.

Video: wall-mounted double-circuit gas boilers Daewoo

You should be careful with Chinese technology, despite its relatively low price. Well, the “unknown to science” brand should be dismissed immediately, no matter how attractive the model may seem.

When choosing between manufacturers, it should be clarified whether there are service centers in the region, how difficult it will be to send equipment for preventive maintenance or replacement based on a complaint. Probably, you should not buy a boiler even from the most popular manufacturer, if it is “exotic” in a given area, and the search for any trifling detail will be difficult.

You may be interested in information about what are

So, in order to choose a really high-quality wall-mounted double-circuit boiler, completely suitable in all respects, you should evaluate a lot of criteria, understand the device, scrupulously study technical documentation on the model you like, compare its technical characteristics with the existing conditions of the planned operation. Don't go for cheap

- a responsible and serious communication system, and very convenient in terms of heating buildings. It is with its help that you can control the temperature in the premises, plus save energy consumption. The center (heart) of the heating system is. In this article we will talk about such a variety of it as a gas wall-mounted double-circuit boiler with a closed combustion chamber. Therefore, first of all, we will determine what exactly a double-circuit unit is, and secondly, why the combustion chamber is called closed.

Imagine a heating system. This, and all this is interconnected. In the water is heated, which moves through the pipes, getting into, where the heat is transferred to the air. After that, the cooled coolant moves back into the boiler, where it heats up again. Such a system, where water moves cyclically, in a circle, is called single-circuit. There is a double-circuit heating, in which two communication lines are combined: heating and. And the water in both systems is heated by one.

The principle of operation of a double-circuit boiler

Let's start with the fact that double-circuit boiler two heat exchangers, and in a single-circuit - one. The water in the latter is heated by gas in the combustion chamber, which then moves towards heating. All the same happens in a two-circuit unit, when it comes only to the heating system.

But when you turn on, thereby opening the hot water supply, which is an integral part of the design heater, shuts off the hot water supply to the heating system, switching it to the second circuit - DHW system. The coolant passes through the second heat exchanger, reducing the temperature to the required level (up to +55…+60°С).

As soon as the consumption of hot water stops, the pressure in the system rises, three-way valve switches it to heating mode. Here the question may arise, but will it not turn out that the disconnected heating network will begin to reduce the temperature regime. It will be and will be, but everything will depend on how long you keep open system DHW. And if you take it within 10-15 minutes, then the changes will be insignificant.

The device of a wall-mounted double-circuit gas boiler

Schematically, the main elements of such a communication network can be seen in the photo below.

Please note that the main heat exchanger is located in the fuel combustion chamber. It is there that the coolant is heated up to + 95 ° С. There is also a burner here.

Open and closed combustion chamber - what is it

To make it easier to understand the peculiarity of these two systems, it is necessary to introduce . This is an example of the simplest open combustion chamber. The fuel has access to oxygen. According to this principle, a conventional oven with a blower operates. The disadvantage of such a system is high flow oxygen in the room, which will lead to the need for additional or frequent ventilation.

But in closed type there is no access to open oxygen in the combustion chamber. Typically, such an oven is equipped with only two holes - and for air intake. Moreover, the latter can be installed as part of the chimney and as a separate pipe. Exhaust gases and vapors are removed through the chimney, and fresh air enters through the air intake. The photo below clearly shows the air intake duct, which is located separately from the chimney.

Attention! A closed combustion chamber is the presence of a fan that creates noise. This is what sometimes repels consumers from purchasing boilers of this type. Today, manufacturers are doing their best to reduce this parameter, and they succeed.

So, having understood the principle of operation and the device of gas boilers with an open or closed combustion chamber, their differences, we can proceed to the analysis of the technical characteristics of the second.

Technical characteristics of the closed type boiler

Choosing a heating boiler for own house, it is necessary to take into account its characteristics. Because this is the basis not only for the efficient operation of the entire heating network, but also for significant fuel savings.

Boiler power

Here it is necessary to take into account the fact that the power of the unit, measured in kilowatts of thermal energy, provides the required temperature regime inside the rooms. If there is not enough power, it will be cool inside the house in winter. If it is overabundant, then fuel consumption will be increased, which, from the economic side of the matter, is unprofitable.

It is not easy to calculate the power of a heating boiler, because for this you will have to take into account a large list of various parameters of the erected house: the materials from which it was built, whether insulation was carried out or not, which ones were installed and in what quantity, and others no less important parameters. But there is an easier way. Usually, the power of the furnace is considered as follows: 1 kW of thermal energy should be consumed per 10 m². This is provided that the height of the ceilings does not exceed 3 m. For obvious reasons, this figure may vary depending on the region. So for the northern regions, the heat consumption will be in the range of 1.2-1.5 kW, in the southern - 0.7-0.9 kW.

Type of heat exchanger

Today, manufacturers offer two types of double-circuit boilers:

1. With separate heat exchangers.
2. With one bithermic.

We have already dealt with the first ones, their work is understandable, but the main thing is that each of them provides its own circuit with heat: heating or hot water supply. And they are located inside the boiler in different places. As for the bithermic heat exchanger, it is a pipe in a pipe. Water intended for the system moves along the inside. Between the pipes in the gap moves the coolant for the heating system.

This is the most simple design both in terms of the principle of operation and heat extraction, and in terms of functionality. Moreover, such a design is a minimum of additional devices responsible for switching, hence the low price of the equipment itself. However, this system has two significant drawbacks:

1. It is better not to install such boilers in systems where it is used. Scale will quickly begin to be deposited on the walls of the pipes, especially in the outer pipe, which will lead to a decrease in their cross section. And this is a decrease in the efficiency of the device, respectively, and the entire heating network.
2. As soon as the mixer opens the water supply, very hot water will pour out at first. And only after a few seconds will begin to act normal.

We add that a bithermic heat exchanger is more often a coil made of copper pipes.

As for separate heat exchangers, the main one is also made in the form of a copper coil with fins, and the additional one, which is responsible for hot water supply, is usually made of stainless steel.

Burner type

Immediately make a reservation that only atmospheric burners are installed in wall-mounted gas boilers. That is, those that work under the influence of mixing air with gas in a natural way, without the use of additional units (turbines and fans). The latter are installed in pressure-type burners, and they, in turn, are used in floor units high power.

Now about atmospheric burners. They can be of two types:

1. Single stage. This is when the device is either on or off. There are no other options for her. Therefore, in order to achieve the required mode of maintaining the temperature regime, the burner turns on and off.
2. Two-stage. There are three positions here: complete shutdown, one hundred percent power (maximum) and intermediate by 50-60%. Positions are set automatically using equipment specially installed in the boiler.
3. Modular. These are the most economical burners in terms of gas consumption, but also the most expensive. They automatically switch from 10 to 100% of power with a gradation of 10%.

Automation

All gas double-circuit boilers are provided with an automation system that controls three nodes. The safety of operation of the heating unit depends on them:

• draft in the chimney;
• the flame burns or not;
• supply gas pressure.

If one of these parameters does not meet the standards or is absent at all, then the boiler simply does not turn on.

Safety Features

1. Coolant temperature control. There are two directions of control: coolant or.
2. Post-circulation coolant. The essence of the function lies in the fact that, which is part of the boiler design, it does not turn off immediately after shutting off the gas. He drives the coolant around the circuit until it cools down. Otherwise, the water in the heat exchanger may boil.
3. Function summer mode. During the warm season, the heating system does not work. But in everyday life it is necessary. Therefore, the boiler heats it through a three-way valve and two heat exchangers. But so that stagnation does not occur inside the entire system, the circulation one turns on once a day and drives water along the circuit.
4. Anti-freeze function. It is used in winter when no one lives in the house. The temperature of the coolant is simply maintained within + 5 ° С.

Advantages and disadvantages

pros	Minuses
Compact, small wall area required for installation.	Power is not the greatest, which does not give wall boilers use in heating systems of large houses.
High reliability of the device, which guarantees one hundred percent safety of operation due to the installation of an automation system.	Boilers of this type are volatile.
Attractive appearance, which will not spoil the design of the room.
It can be installed inside the house, for example, that is, there is no need to equip a separate boiler room.	Difficult installation that requires experience and knowledge. With your own hands, if you are a layman in this matter, better installation do not produce. Moreover, this is due to the connection to the gas pipe.
High heating rate of the coolant. Literally a few minutes after turning on the heating gas, it will already start working.
Air is not consumed from the premises.	The service life of single-circuit units is much higher.
There is no need to equip ventilation with a higher draft.

Manufacturers and models

It is difficult to say which brand or model is better to give preference to. And even the ratings compiled do not reflect reality, because the market is filled with double-circuit gas boilers wall type with a closed combustion chamber from different manufacturers. Here are foreign analogues, and domestic ones. But, according to experts, many European models in Lately gave up positions. The reason is the transfer of production to China.

However, let's try to define best options. Boilers come first BAXI from an international concern, whose representative offices are scattered around the world and in Russia, including. Although originally an Italian brand, the headquarters in this country is located. noted high quality and long term operation.

In second place we will put equipment from a German company Bosch . It makes no sense to talk a lot about these boilers, because they have high performance. The only negative is the high price.

Another German manufacturer of boiler equipment, producing units under the brand name Vaillant . Again, this is a high quality and price point.

It should be noted that and Russian manufacturers offer boilers with excellent technical qualities according to affordable price. The brand has gained particular popularity in recent years. Protherm , which has designated itself as the most reliable heating unit in its category.

Of course, it is necessary to include in the list the brands that are well known to consumers. Let's just list them: Ariston , Electrolux , AEG , wolf , Ferolli .

Features of the installation of double-circuit gas boilers

As mentioned above, the gas boiler must be installed by a competent specialist, so we will describe how to properly install in the general case.

A photo	Description of works
	Everything needs to be prepared
	We fix our bracket on the screws.
	We fix the boiler.
	We install the device to communications: gas, water, coolant supply and return circuits, heating pipes.
	Now you need to connect the shut-off valves to the nozzles. The gas valve is connected first, then the water valves.
	After that, all communication networks are connected to them.
	A coaxial chimney is installed.
	We feed our boiler into the terminal box.
	We check the correct connection of the wires.
	And systems. We pay attention to safety precautions.

As we have seen, connecting the boiler does not require special knowledge. However, it is worth noting that important role the quality of raw materials plays a role in the operation of the system. Therefore, be sure to read the instructions for the boiler in order to know exactly the features of its use.

Article

Regardless of fluctuations in world energy prices, heating services remain high, which forces consumers to implement a range of energy-saving measures. These include not only the insulation of houses and the replacement of windows with energy-saving structures, but the modernization of heating systems by replacing pipes, installing modern boilers, or switching to alternative views fuel.

Reliable heating boiler - a guarantee of warmth and comfort in the house

Each consumer solves this problem in his own way, but one thing is for sure: with an obsolete boiler, all energy saving measures will not give a tangible effect. A reliable boiler, regardless of the fuel used, is the heart of any heating system. It is from his work that the warmth in the house depends, which we so need in the cold season. But so that the cost of heat does not ruin family budget, the old boiler must be replaced with a new, modern and economical one.


The range of boilers is unusually large, and the consumer can choose a model designed both for heating a private house and for organizing autonomous heating in an apartment.

Classification of boilers and the general principle of their operation

Heating boilers are classified according to several parameters:

• Type of fuel.
• Power.
• The number of contours.
• Installation methods (floor or wall).
• Type of combustion chamber (open or closed).

If in an electric heating boiler water is heated directly by heating elements, then in gas, solid fuel and diesel boilers, an open flame is used to heat the coolant, which is created by burning fuel in a special chamber. Fuel combustion chambers are open or closed, and the combustion process and temperature conditions are controlled reliable system automation.

The principle of operation of any heating boiler is simple. The fuel burns, heats the coolant, which through the radiators gives off heat to the room. Diesel boilers use open chambers, and various models of gas and solid fuel boilers can have both open and closed combustion chamber designs. Consider them distinctive characteristics, as well as advantages and disadvantages.

Features of an open combustion chamber

An open combustion chamber is a burner that heats a coil, through thin tubes of which a coolant (water) flows. As you know, the presence of oxygen is necessary to maintain the combustion process. The design of the open chamber provides for the intake of oxygen from the surrounding air through special channels. Exhaust gases are removed naturally through the chimney.

In the room where the boiler is installed, there must be window with opening window, which provides a natural influx of fresh air and eliminates the high concentration of carbon monoxide. The design of an open combustion chamber is quite simple, and Maintenance such boilers consists of the following activities:

1. Burner cleaning.
2. Cleaning the coil from scale.
3. Chimney cleaning.
4. Control of the operation of automation devices.

It should be borne in mind that with all the advantages and disadvantages of open combustion chambers, the price of such boilers is an order of magnitude lower than the cost of boilers with a closed chamber, which is often the main criterion for choosing heating equipment. And tangible fuel savings can only be achieved by installing a water pump, as well as carefully insulating the chimney and walls of the house.

Features of a closed combustion chamber

A closed combustion chamber is a closed zone with a burner, where air is injected through a coaxial chimney, which is a pipe in a pipe, and combustion products are removed. Forced air circulation is provided through the use of an electric fan, which makes the heating system dependent on the availability of electricity, and also increases the noise level in the room.

The forced air is heated by the exhaust gases, which contributes to complete combustion fuel. This, in turn, increases the efficiency of boilers with a closed chamber and improves their environmental safety. Boilers with a closed chamber are different simple installation, they do not require bulky chimneys, and they are great for organizing autonomous heating in apartments.

Disadvantages include regular maintenance, significant energy consumption and the risk of freezing of the fuel combustion area due to the short length of the coaxial chimney. The fuel savings offered by closed chamber boilers are usually offset by the costs of electricity, maintenance and the purchase of spare parts needed in the event of a repair.