Coaxial chimney Vaillant - what are the advantages. Features of the device of coaxial chimneys: assistance in choosing and installing Types of coaxial smoke exhaust pipes

Increasingly, in the manufacture of flue gas systems, a coaxial chimney is used for gas boiler... On condition correct installation, the coaxial pipe copes with two tasks at once: it removes the combustion products and provides sufficient air flow for the operation of heating equipment.

There are several types of chimneys, differing in material and design, as well as different technical characteristics.

Coaxial chimney - what is it

Coaxial chimney is a simple design. In fact, they are just two pipes different diameters inserted one into the other, so that there is a gap of several cm between the walls of the outer and inner contours.

All pipes, regardless of the design features and the material used, can be conditionally divided into two groups:

Collective coaxial chimneys for gas boilers are manufactured exclusively at the factory, installed during the construction of a building. To increase the traction characteristics, they have an inner layer of thermal insulation.
Individual systems - chimneys designed for domestic use and connected to one heating device. Mostly plastic chimneys are used for condensing boilers, due to their low cost. Two-channel stainless steel pipes are used much less often.

The efficiency of the flue gas system largely depends on the right choice pipes. First you need to find out about how the chimney works, as well as on which boilers you can put the coaxial pipe.

The principle of operation of a coaxial chimney

The coaxial pipe is designed for the simultaneous removal of combustion products and air intake from the street. The gas circulation process is carried out through two channels.

The principle of operation of the chimney is as follows:

For the efficient operation of the pipe, you will need to: strictly observe the SNiP for coaxial chimneys, carry out a preliminary calculation of the system, and also perform the correct assembly, including the installation of safety assemblies: a condensate trap, an anti-icing nozzle, etc.

On which boilers can a coaxial pipe be installed

Chimneys of coaxial type are designed for connection to condensing and turbocharged boilers with a closed combustion chamber, forced or natural system smoke removal.

The pipe is optimally suited for parapet units and convectors. It is possible to install a coaxial system on a boiler with an atmospheric burner if the pipes are made of stainless steel.

Simple design significantly increases work efficiency gas equipment... Almost all modern models are connected to two-channel systems. It is allowed to install steel coaxial flues for single-circuit and double-circuit gas boilers, regardless of the principle of operation and design of the combustion chamber.

To determine if you can install two-channel chimney, you should be guided by the parameters specified by the manufacturer in the technical documentation. Usually, it contains detailed instructions and standards, as well as requirements for the installation of a flue gas system.

Some models of condensing turbocharged boilers have a separate system for removing combustion products through two separate outlets. One for the removal of combustion products, the other for air intake. In such modifications, the connection of the coaxial pipe is not advisable.

Types of coaxial smoke exhaust pipes

When choosing a coaxial pipe for gas equipment, it should be remembered that only branded chimneys made by the same company as the unit itself are suitable for some brands of boilers. , - all these manufacturing companies manufacture equipment with non-standard sizes outlet pipes. Therefore, the use of branded components is considered optimal for the manufacture of a smoke exhaust system.

In all other cases, the choice mainly comes down to the selection of a suitable pipe material. The structure of the systems is made of aluminum, of stainless steel and plastic. In domestic conditions, the most popular are plastic pipes and stainless steel products.

Two-channel plastic chimneys

Plastic chimneys are made of a special heat-resistant material that can withstand a maximum heating temperature of up to 205 ° C. Pipes are connected to condensing equipment gas type... The advantages of plastic:

Low weight.
Low cost.
Simple installation.

The disadvantages include the relatively short service life of plastic coaxial chimneys, as well as the limitations associated with the ability to connect to conventional gas boilers... It is allowed to use the system only in conditions of low-temperature gas removal mode.

Coaxial stainless steel pipes

The stainless steel used in the manufacture of the chimney is acid resistant and can withstand more than plastic pipe temperature, up to 550 ° С. Manufacturers offer chimneys of two designs:

When choosing a coaxial pipe, first of all, they are guided by the recommendations of the manufacturers of heating equipment specified in the technical documentation.

Coaxial flue installation regulations

State codes and regulations for the installation of a coaxial chimney for a gas heating boiler with closed chamber combustion, set out in. Design, calculation and installation works are carried out in accordance with regulatory documents. Failure to comply with the recommendations leads to the refusal of the Gas Service to put the heating system into operation.

The standards regulate the distance from the coaxial chimney to the window, doorways, nearby buildings. Specifies the minimum requirements associated with the manufacture of fire protection diffusers and other safety standards. In particular, SNiP stipulates:

The location of the coaxial chimney on the facade - the head is placed at least two meters from the ground level. The size of the hole in the wall must exceed the diameter of the coaxial pipe by 1 cm, in case of passing through a brick one, by 5 cm for a wooden wall.
The use of coaxial chimneys in multi-storey residential buildings- the norms allow the installation of pipes of this type, subject to following conditions... The minimum distance to window and door openings located at the same level is not less than 0.5 m. To the window located above the chimney, not less than 1 m.
If a condensing boiler is used, there is no danger of poisoning by the flue gases discharged through the coaxial pipe. Provided that the system is correctly installed, the effect of the flue gases on the residents of the upper floors is negligible. Violations during the installation process lead to condensation on the windows of neighbors.
Fire safety standards and requirements. The size of the gap between wooden wall and a coaxial chimney of 5 cm. The minimum clearance is due to the fact that during operation, the surface of the outer contour of the pipe practically does not heat up. Install non-flammable materials between the coaxial pipe and the wood wall. It is optimal to use basalt insulation.
The regulated distance from the coaxial chimney, relative to windows and doors of neighboring houses and other buildings, is not less than 1.5 m. The site should not be blocked by walls, pillars, trees, etc. The removal of combustion products from the condensing boiler into a conventional chimney, instead of a coaxial one, is prohibited.
A coaxial chimney can be either horizontal or vertical. The installation of a collective smoke exhaust system is carried out only after obtaining permission from the gas service. It is not allowed to connect boilers with forced and natural discharge of combustion products into the same network.
Horizontal section - laying a two-channel chimney through an adjacent non-residential premises is allowed only if the pipe length does not exceed 3 meters. In turbocharged models, with the presence of the function of forced discharge of combustion products, it is allowed to increase the horizontal section up to 5 m.
Limitations on the output through the facade. Care must be taken to prevent condensation from dripping onto the ground. The pipe is installed at a slope towards the boiler. If there is a condensate drain, it is allowed to slope the outlet pipe to the ground to drain rainwater. With a collective connection, it will be necessary to agree on the disposal of the accumulated condensate with the sanitary and epidemiological authorities.
Installation standards - the coaxial chimney must protrude from the wall at a distance of at least 30 cm. For turbocharged boilers with a chimney section of about 1 m, a narrowing diaphragm must be installed - a unit that compensates for the insufficient length of the chimney. A diaphragm in a coaxial chimney is needed to limit the flow of air into a closed combustion chamber. Turbocharged boilers are designed to use a 5 m chimney. The diaphragm eliminates the difference.
Coaxial pipe maintenance - the system is serviced annually, at the beginning and end of the heating season. The accumulated condensate is removed, the tightness of the joints and the absence of burnout in the structure are checked.

Requirements for the safe operation of coaxial chimney systems may change, therefore, before purchasing and installing, you should consult a specialist.

Mounting options

Complete with coaxial chimney, factory assembled, must be included detailed instructions for installation. Compliance and careful implementation of these recommendations affects the operation of the boiler and the efficiency of the flue system. According to experts, the main reason blowing out of the boiler, the appearance of frost or ice, is associated with errors in calculations and when connecting the chimney.

Horizontal installation of coaxial pipes

Horizontal installation is carried out taking into account technical characteristics building. Initially, the place where the pipe exits from the wall is selected. There are restrictions related to the distance to the nearest neighbor's window when removing a horizontal coaxial chimney from the wall, which must be carefully observed.

Additionally, the following parameters are calculated:

The height of the pipe - from the outlet of the boiler to the through-hole in the wall, for floor-standing gas boilers there must be a height of at least 1 m. It is not allowed to lead the pipe directly from the outlet to the street. For wall-mounted gas boilers, a height reduction of up to 0.5 m is allowed.
The number of rotary couplings on the site should not exceed 2 pcs.
The maximum length of the horizontal section is 3-5 m, depending on the boiler model. To lengthen the pipe, a coupling with heat-resistant sealing rubber bands is used. The use of silicones and sealants is prohibited.

The peculiarity of using a two-channel chimney in winter is increased condensate production. The reason for moisture loss is that the system was originally designed for more favorable conditions exploitation. With an increased formation of condensation, it will be necessary to insulate the pipe.

Vertical installation of two-channel pipe

Vertical installation of the chimney provides for two connection methods:

How to properly install a coaxial chimney pipe

Exists general rules and regulations helping to install the chimney in such a way as to avoid further operational problems. Recommendations separately stipulate:

System outlet through the wall.
Connection to the boiler.
The possibility of extending the two-channel system.
Anti-icing and wind protection.

Coaxial chimney outlet through the wall

It is actually quite simple to bring the coaxial flue system through the wall. The difficulty is to determine the optimal place for this task. Fire safety requirements are imposed on the location of the coaxial chimney. Some norms are described in SP 60.13330.

Recommended angle of inclination of the horizontal section 3 ° to the side heater... If a steam trap is installed, it is permissible to incline to the other side.
The maximum length of the horizontal section of the coaxial pipe is from 3 to 5 m, depending on the technical parameters of the installed boiler. More than two corners may not be used along the entire length of the chimney.
Passage node brick wall done with a gap of 1 cm. The gap is not sealed non-combustible material and closes with a special overlay.
Passage node wooden wall expands by 5 cm compared to the pipe diameter. Basalt insulation is placed in the resulting gap. Alternatively, a hole around the coaxial chimney in the wooden wall of the house can be repaired with special fire-resistant foam.
A tee with a condensate trap and an inspection channel for cleaning is installed.
The concentration of exhaust gases when connecting a coaxial chimney is low. But for safety reasons, it is recommended that minimum distance the exit of the coaxial chimney above ground level was not lower than 2 meters from the ground. So, you can completely neutralize the insignificant danger of gas combustion products.

Installation work is carried out in accordance with the instructions provided by the manufacturer.

How to connect a two-channel chimney to a boiler

One of the common mistakes when connecting a coaxial smoke exhaust system is the use of improvised means, which is a gross violation of safety and operation. The norms prescribe the use of special adapter for connection. It is forbidden to install a self-made branch pipe from a piece of stainless pipe.

Immediately after the outlet pipe, a tee with a condensate collector is mounted, after which the pipe is raised up by 0.5-1 m, the angle is set and the chimney is brought out through the wall. Before commissioning, check the quality of traction.

How to lengthen a coaxial pipe

It is not always possible to install the boiler in such a way that the chimney is no more than 1 m. In some cases, it will be necessary to extend the pipe lengthwise. The construction is assembled on the principle of "dad-mom". The pipes are mounted over condensate. For angles use 45 ° and 90 ° swivel couplings.

Do not seal joints with silicone. The adapters are fitted with rubber bands that can withstand heating up to 250 ° C. During installation, it is required to minimize the number of turns and corners as much as possible in order to ensure better traction... Fastening clamps are installed along the entire length.

How to protect the coaxial flue gas system from icing

Icicles on the head indicate obvious irregularities during the installation works... As a rule, if design calculations and subsequent installation is done correctly, there is no chance of icing.

You can additionally protect the chimney from ice formation as follows:

The de-icing nozzle is a component that helps to eliminate the problem of pipe freezing, even with improper installation.
If there is no condensate drain in the pipe structure, the slope should be towards the boiler, which will lead to condensate draining into the tee and a special collector. When, despite the observance of the slopes, frost still forms on the head, this indicates incorrect calculations. If a condensate drain is installed, it will be necessary to protect the brick from gas combustion products by extending the pipe head 50-60 cm from the wall.

When using individual coaxial flues in low-rise residential buildings, the installation of an anti-icing nozzle is mandatory.

The maximum boiler power allowed for connection to a coaxial chimney is 40 kW. Installation of equipment with high performance parameters leads to insufficient draft, increased condensate production and icing.

How to protect a two-channel chimney from the wind

Blowing out of the boiler, the presence of a reverse draft is unacceptable. If the system is not protected from wind and draft, combustion products will enter the room, which often leads to carbon monoxide poisoning of residents.

Backdraft can be avoided as follows:

Installation of windscreen and diaphragm.
Correct location of the pipe under the window, in relation to doorways and surrounding buildings.

The distance from the window, on the outer side of the wall, is not less than 1 m. If you place the chimney closer, then a draft will form when the window opening is opened.

Pros and cons of coaxial smoke exhaust systems

Each smoke exhaust system has certain advantages and disadvantages, without exception. When deciding how justified the use of a coaxial pipe is, you should pay attention to several important factors:

The cost of construction and installation.
Advantages and disadvantages.
Boiler type.

Cost of a coaxial kit for a chimney

Compared to a conventional chimney, a coaxial chimney is more expensive. A standard meter kit will cost about 3,000 rubles. Each additional meter for lengthening, another 1800-2000 rubles. Knee and sealing rubber in 1500 and 300 rubles. respectively.

In general, the assembly of the system, provided that the connection is carried out independently, will cost from 6 to 10 thousand rubles. The pleasure is not cheap. For some types of gas equipment, there is no alternative to installing a coaxial pipe. For example, it is forbidden to use a conventional chimney for a condensing heating boiler.

Some, wishing to reduce the cost of the flue system, use improvised means. On the Internet, you can find videos and articles on how to use sewer pipes as a chimney for a condensing boiler, which is dangerous and leads to carbon monoxide poisoning of the residents of the house.

It is better not to save on safety and buy the chimney recommended by the manufacturer of heating equipment.

Advantages of a chimney from coaxial pipes

The main advantage of the coaxial flue gas system is that during the operation of a gas boiler, air is burned, taken not from the room, but from the street. As a result, the requirements for room ventilation are reduced and total area the room used for the boiler room.

The existing standards allow installing the boiler in an unventilated room, since the need for ventilation in the boiler room is minimal. If we compare, then a boiler with a closed combustion chamber, during operation, uses as much oxygen from the room as is necessary for the combustion of one burner of a gas stove.

The main advantages of a coaxial pipe from a conventional chimney are as follows:

Installation speed.
Suitable for almost any heating equipment.
Provided correct installation, good traction performance.
Suitable for use in apartment buildings.

Given the merits of two-channel designs, it is not surprising that such systems have become widespread.

Disadvantages of two-channel pipes

Two-channel pipes have their drawbacks:

Coordination with the Sanitary and Epidemiological Supervision is required. During work, it stands out a large number of toxic condensate. It is forbidden to pour it into the ground. Disposal in specially designated places is allowed.
In practice, if you install a two-channel design in a private house, then all possible claims will be reduced to the wishes of the owners of the house, from representatives gas service, dispose of condensate properly. For collective systems, you will have to get permission from the sanitary and epidemiological supervision.
Large amount of condensation. No matter how you insulate the two-channel pipe, the amount of condensate produced will still be large. Even minor irregularities during installation lead to icing of the outlet, a decrease in thrust characteristics, etc. When installing a coaxial chimney, you will need to insulate the pipe from condensation.

Typical mistakes during installation and operation

The main mistake still remains self-connection pipes by a person with no special skills. The main recommendation of installers is to invite licensed workers to carry out the work, capable of performing calculations and assembling the structure without violations.

As practice shows, certain violations are more common than others:

Incorrect system design - there is a direct dependence of the outlet temperature on the length of the pipe. Exceeding the distance limits leads to cooling of the escaping smoke so that it is not able to heat the accumulating condensate. As a result, icicles form on the head.
Failure to comply with fire regulations. The length of the horizontal section of the pipe outside the wooden building is increased to 60 cm. Fire-prevention gaps must be made.

As a separate point, one can single out the absence of protective assemblies and elements, which somewhat raise the cost of the structure, but increase the efficiency of the smoke exhaust system.

Mandatory component vertical system is a set for draining condensate, as well as a valve to increase the draft. Horizontal structures require wind protection, a diaphragm, and an anti-icing module.

Correct calculation and qualified work, in accordance with the existing SNiP and SP, guarantees effective work coaxial chimney throughout the entire service life.

In the middle of this device, special bridges are provided that do not allow the elements to come into contact with each other.

The coaxial chimney is installed complete with a gas boiler equipped with a closed combustion chamber.

Each of the contours of such a channel has its own task:

one of them is responsible for flue gas discharge from the combustion chamber of the boiler unit;
through the second is carried out fresh air supply, which is important for the complete combustion of fuel.

For boilers with a closed firebox, it is necessary to install chimneys with a length of no more than two meters. This is important because the larger the size, the thrust will be poor, therefore, the fuel will not burn completely. This is due to the formation of peculiar vortices that interfere with the exit of the products of the chemical reaction of the oxidation of the substance and the entry of air flows from the outside.

Advantages and disadvantages

As for the advantages of the coaxial design, the following points can be attributed to them:

Quite high efficiency.
Small size. When installing a conventional chimney, two pipes are required, and in the case of a coaxial structure, one product is required.
There is no need for an additional ventilation system.
Environmental friendliness.
Staying in a boiler room is absolutely not harmful to human health, since the heating system takes oxygen not from the room, but through canals from the street.
Economical fuel consumption.
Due to the constant flow of cold air, the walls cannot become overheated.

The only drawback of the device is as follows: when sub-zero temperature a pipe with a smaller diameter may freeze up, since the flue gases give off their heat to the inner channel along the way and at the outlet already have a rather low temperature. That is why the formation of condensate accumulations in the pipe is normal. With a decrease in indicators to -15 ° C, a rolled metal product may succumb to severe freezing, which leads to undesirable consequences.

It is believed that coaxial structures are not suitable for the harsh climate of Russian cities. At first, this system was developed for the southern countries. However, many experts agree that pipe freezing is the result of an illiterate design of this system. Whatever the cause, the end effect is the same: the galvanized chamber and burners quickly deteriorate. Repairing such equipment is considered quite expensive.

Most often, such problems are observed precisely in those types of chimneys that are manufactured according to parameters that can significantly increase the efficiency. For this, the diameter of the pipe is made as small as possible, which practically brings the temperature indicators of the flue gases to the dew point.

For southern countries, such values \ u200b \ u200bdo not affect anything, but in Russia, with the first serious decrease in temperature, freezing of the pipe entails a complete installation heating system... Manufacturers can only shrug their shoulders, as the tests this device are not carried out in such conditions.

Summarizing all of the above, we can conclude that its resistance to negative temperatures... It is worth noting that this system is negatively affected by significant voltage drops, as well as a complete power outage.

Selection of a chimney for a bath

There is no individually designed chimney system for arranging heating in a bathhouse. They select it depending on the type of boiler, the type of fuel and the design characteristics of the room. The device of such chimneys for different ovens almost the same. Coaxial pipe is usually manufactured made of high quality plastic or aluminum... When purchasing such a system, you must pay attention to the presence of all jumpers, which are designed to prevent the pipes from touching.

All recommendations for proper design can be found in the Russian SNiP 2.04.08-87 "Safety rules in the gas industry." Without special skills and knowledge, these requirements will be difficult to understand. To simplify, you can purchase a completely turnkey system, which includes all required certificates... By their design, such devices are horizontal and vertical.

Manufacturers

A universal option for most popular gas boilers is the coaxial design of the STOUT brand. Everything constituent elements systems are ideally matched to each other, easy to install and maintain, adapted for use in our country.

A variety of elements allows you to create absolutely any smoke exhaust system. The manufacturer gives a two-year warranty on all products. Technological process manufacturing is carried out at the same factories in Italy, where a similar, but more expensive product is produced. STOUT is the choice of those who do not overpay for the promoted brand name, but are used to choosing only high quality.

Coaxial chimneys of the company Baxi produced for boilers that run on gaseous fuels. Their construction is made of the highest quality stainless steel.

Company Immergas manufactures horizontal coaxial flues. It is possible to use such a device for gas boilers, as well as for units operating on liquid fuel.

Firm Buderus is engaged in the manufacture of horizontal chimney systems. Two types of steel are used for their production: galvanized and stainless steel.

Coaxial chimney for gas boilers Hermann manufactured in certain sizes: diameter of the inner pipe - 6 cm, outer - 10 cm. Such systems are performed both horizontal and vertical.

Coaxial chimneys of the company Vaillant produced with some design features that allow the device to be used in conjunction with boilers from other companies.

Korean manufacturer Navien manufactures chimneys that can be used together with floor or wall-mounted boilers power not exceeding 75 kW.

Coaxial chimneys of a popular company Viessmann produced in several versions with diameters 6/10 cm, 8 / 12.5 cm, 10/15 cm. By design, they can be both vertical and horizontal.

Firm Protherm manufactures both types of coaxial flues in sizes 6/10 cm and 8 / 12.5 cm.

The design of similar devices of the company Daewoo designed in such a way that the installation can be carried out from either side of the boiler.

Horizontal and vertical chimneys of the company Ariston are made of enamelled steel.

Installation requirements

Installation of such a design has its own rules, which should be described in the instructions attached to the equipment. Gas supply services and the Ministry of Emergency Situations can make adjustments and additions.

When installing a coaxial chimney, it is important to take into account certain requirements:

The design of the pipe is made in such a way that there should be no back thrust. A special valve is installed in front of the firebox, which prevents flue gases from blowing into the room.

Passing a coaxial device through a wooden wall

In SNiP and fire safety rules, there are no recommendations for the installation of horizontal chimneys. However, there are general requirements, according to which the passage of the pipe through a wooden wall must be carried out with certain cuts. To a greater extent, this condition is met not in order to protect the structure from fire, but to exclude incidents with fire services in the form of fines and instructions.

The passage of a coaxial chimney through a wall made of non-combustible materials

The process of preparing the hole required for the output of the pipe is not particularly difficult. The opening is cut required diameter whose slope is directed towards the ground. The size of this hole must be equal to the corresponding chimney value. A special extension cord is inserted into the opening made, which fulfills the requirement for the location of the connection to the wall.

It is possible to protect the chimney from icing only by installing additional elements. It is recommended to purchase special attachment which will prevent condensate from freezing. This device will also help in case of incorrect design and subsequent installation without the desired slope. The nozzle helps to maintain the temperature inside the pipe at a certain level.

The distance from the gas supply duct to the chimney should be approximately 60 cm.

Installing a coaxial device

It is important to know that non-observance of the rules for the construction and installation of such a structure can nullify all the advantages of this device.

Installation instructions:

Coaxial chimney - new technical solution, which replaced the standard chimneys. A feature and great advantage of this device is that oxygen for combustion in the boiler furnace is taken from the street, and not from the house.

Coaxial chimney designs

Chimneys are used for different types boilers:

B - chimneys for boilers with open chamber burning;
C - chimneys for boilers with a closed combustion chamber.

In high-rise buildings you can find a variant of a collective chimney to which individual boilers are connected. Such a chimney goes to the roof

Coaxial chimneys are mounted in two positions:

vertical;

horizontal.

Only the installation method differs, but the principle of the chimney is the same. Like everyone else engineering systems, it has both advantages and disadvantages. Let's consider them.

Advantages

Structurally, the chimney consists of two pipes, one plays the role of an outer shell, the other inner. Combustion products - exhaust gases - are discharged through a pipe with a smaller diameter. Air enters the combustion chamber of the boiler through the outer pipe to maintain combustion. This system provides a compact and aesthetic appearance, takes up little space. The system provides heating of the incoming outdoor air with exhaust gases, which increases the efficiency of the boiler.

Another important advantage of this system is its fire safety. When flue gases are removed, they are cooled with air, which enters the combustion chamber of the heating unit, reducing the risk of fire to zero. Additional insulation of the chimney with fire resistant materials is not required.

A similar chimney system can be installed on Various types boilers:

on gas;
on liquid fuel;
solid fuel.

Disadvantages of a coaxial chimney

Freezing. This is probably the main and most serious drawback when installing a horizontal chimney.

The first models of coaxial chimneys that appeared on the Russian market were not designed for such low operating temperatures - -15 - -30 ° С. They are designed for countries with milder climates. As a result - the possibility of freezing of the chimney and failure of the heating unit.

Although not all experts are so categorical. In their opinion, the main reason for the freezing of the coaxial chimney is the incorrect heat engineering calculation. In this case, the boiler efficiency depends on the supply air temperature. In pursuit of an increase in efficiency, the designers reduced the diameter of the exhaust pipe. In this case, the temperature of the flue gases drops below the dew point, which leads to an increase in the formed condensation inside the exhaust pipe and freezing. To reduce the effect of this factor, it is necessary to increase the temperature of the flue gases by increasing the diameter of the pipe. A properly sized coaxial chimney must not freeze up.

When installing a vertical coaxial chimney, we face the problem of collecting condensate. Since the problem is known to all manufacturers, the models of coaxial chimneys designed for vertical installation, complete with a condensate collector.

Rules for installing a coaxial chimney for a gas boiler

When installing a coaxial chimney yourself, you must read the manufacturer's instructions. Be sure to adhere to the rules for installing a coaxial chimney.

When installing, use only materials and components that have been tested in the state gas supervision; it is forbidden to make any changes to the configuration and construction of the chimney.
During installation, it is forbidden to use materials not manufactured by the manufacturer of the chimney; the necessary additional components can be purchased only at service centers.
All parts of the chimney are firmly connected and tested for flue gas leaks.
The use of sealants and adhesives forbidden.
It is forbidden to dock pipes in the thickness of the wall, it is necessary to provide a joint outside of it.
A horizontal coaxial chimney is installed (unless otherwise specified by the manufacturer of the boiler): for condensing boilers 2-3 ° towards the boiler, for classic 2-3 ° outwards, ensuring the drainage of condensate and no precipitation entering the boiler.
The length of the coaxial chimney depends on the boiler model, the complexity of the chimney route and ranges from 1 to 7 m (maximum length for a straight-line installation for a boiler with a turbine installed, with a capacity of more than 30 kW.).
It is forbidden to equip the outlet of the coaxial chimney below ground level into the window pit of the semi-basement room.
Remember, for breakdowns and accidents during the operation of the chimney, the installer is responsible.

Installation diagram of a coaxial chimney

The exit of the coaxial chimney through the enclosing structures must comply with a number of rules and requirements. Since boilers of type C are with a closed combustion chamber, they can be installed in all types of premises. Regardless of the presence of windows of the ventilation system and the volume of the room itself, several standards must be adhered to. The photo shows the requirements for installing a coaxial chimney in different versions:

a - the minimum distance from the axis of the chimney to any opening element of the facade of the house;
b is the minimum distance from the axis of the chimney to any air intake;
c - the minimum distance to the sidewalks (to reduce the distance, a grill with a deflector is installed, in this case the distance will be 0.15 m);
d is the minimum distance from the ground;
e - the minimum distance from the axis of the chimney to the wall at an angle of 90 ° with opening elements or air intake holes; (0.15 m with a deflector);
f is the minimum distance from the axis of the chimney to the wall at an angle of 90 ° without opening elements;
g is the minimum distance to green spaces;
h is the minimum distance to the gutter system or vertical pipeline.

Choosing a coaxial chimney

When choosing a coaxial chimney, first of all, you need to pay attention to the recommendations of the boiler manufacturer. There have been cases when the service center did not accept the equipment for warranty through the installation of a coaxial chimney that was not recommended for this boiler.

The coaxial chimney must ensure not only the outlet of flue gases, but also completely ensure the intake of oxygen from the street, therefore, its reliability is very important. It is worth choosing from trusted foreign brands: Baxi, Vaillant, Navien, Ferroli, Ariston, Viessmann.

Coaxial chimney Baxi

Chimneys are made of stainless steel and high-strength polymer materials... The standard kit includes a 1 meter flue pipe, 90 ° elbow, wind protection nozzle, decorative rings. If you need to use an extension cord, purchase it separately. It should be noted that for a chimney up to 1m long it is necessary to install a narrowing diaphragm on the boiler air duct. The procedure is carried out to compensate for the draft, since the boiler fan is designed for maximum length chimney (5m), and in the absence of a diaphragm, a large amount of air will enter the combustion chamber, which will lead to a decrease in the boiler efficiency. To protect against freezing, the coaxial pipe should protrude from the wall for the length of the tip, no more. If the length of the pipe is longer than necessary, the excess is cut off from the inside.

Photos of the main Baxi coaxial chimneys:

Chimney coaxial Vaillant

Vaillant completes boilers own production coaxial chimneys. Correspondence of the size of the nozzles is the key to the successful operation of the boiler. Also, Vilent coaxial chimneys can be purchased for boilers from other manufacturers.

Coaxial chimney Navien

Smoke removal systems Navien from the Korean company are well recommended in the heating equipment market. Chimneys are produced for wall and floor boilers up to 75 kW. The cost of Navien coaxial chimneys is slightly lower than its European competitors, while the quality of performance is not inferior to them.

The German company Vaillant, which specializes in the production of autonomous heating systems, has always been one step ahead of its competitors, offering consumers the latest technological solutions... She managed to achieve incredible success in various niches of the household heating equipment market, including in such a specific area as the production of exhaust gas removal systems.

Today, the Vaillant company, being one of the industry leaders, is actively developing the direction of coaxial chimneys - a new global trend. In this article, we will take a closer look at one of the latest developments of German engineers - the Vaillant 60x100 coaxial chimney, which is designed for units with a closed combustion chamber.

The design is made in the classic "pipe-in-pipe" format, which provides an effective intake of fresh air and rapid removal of exhaust gases. The coaxial chimney Vilant provides complete isolation of the processes of air supply to the furnace and smoke removal. The installation of such a chimney not only helps to maintain the optimal level of humidity and the amount of oxygen in the room, but also increases the coefficient useful action boiler by a few percent.

The principle of operation of the Vaillant chimney with all the perfection of the design is quite simple. The forced draft burner, which is located in the boiler, throws exhaust gases outside through the inner pipe, and fresh air is sucked in from the combustion chamber through the outer pipe of a larger diameter.

This design is compact and easy to use and install. The Vaillant smoke extraction system cannot be compared to a traditional chimney. A coaxial pipe can be installed in absolutely any room, and quite quickly. To install a chimney in an apartment, you need to make a small hole in the wall for the unimpeded removal of gases.

The versatility of the German Vaillant coaxial chimney is noted by many experts. It can be installed on either the right or left side of the boiler.

What is included in mounting kit? It includes:

Elbow 90 degrees with a flange for aggregation with a boiler and specially provided holes that make it possible to take a sample of combustion products;
750 mm coaxial chimney section;
Cuffs for decoration of the inter-wall passage;
Mounting kit for installing screws, gaskets and clamps.

The Vaillant coaxial chimney is used for horizontal exhaust gas discharge and rapid air flow into the combustion chamber. The total length of the structure is 1 meter.

Outcomes

If you do not have the opportunity to equip a full-fledged exhaust gas removal system, this does not mean that your only choice is an electric water heating boiler. Today, the installation of a gas or solid fuel boiler, requiring additional installation gas exhaust systems, possible in any room. The coaxial Vilant design, which has proven itself among European consumers, will help you in solving this issue.

Any heating equipment: stove or heating boiler, fireplace or even simple gas water heater connects a common feature: they need to recycle air, which is saturated with combustion products. This is not only a guarantee of comfort, but also safety. Failure to comply with the norms for installing chimneys can even lead to sad consequences - carbon monoxide poisoning.

The latest solution for modern technologies heating is a coaxial chimney. It allows you to significantly reduce the volume of the chimney, moreover, in the process of operation, air from the room is not used at all, which is undoubtedly an important advantage. This type of chimney is suitable for boilers with a built-in exhaust fan (forced draft). It is much shorter and more compact than a conventional traditional pipe. Its European quality is combined with an excellent price.

The principle of operation of a coaxial chimney

The smoke exhauster built into the boiler system allows air intake from the outside through the outer pipe simultaneously with the removal of flue gases through the inner pipe. Since the air draft is practically ensured, then outer tube has a small diameter and length corresponding to the layout of the installation. Exhaust air containing an admixture of combustion products is discharged from the boiler through an inner pipe. It is also shorter than the traditional one, and thus the boiler does not take up much space. The coaxial chimney is made of modern reliable acid-resistant materials, therefore inner tube does not react with harmful impurities, that is, it is not subject to destruction.

The structure of such a chimney is such that the flue gases do not enter the air duct during exhaust. All this must be taken into account when designing a coaxial chimney, installation and fire safety standards as well. Another important condition for its reliable functioning is the tightness of the connection of the external air duct and branch pipe.

Installation SNiP

Gas-fired heating systems are somewhat different from coal and wood stoves... Therefore, if a coaxial chimney is installed, the installation standards are also different.

In the case of this type of chimney, the combustion products can be discharged into the atmosphere through outer wall premises. In this case, in particular, there is no need for a vertical channel from the system, through which the combustion products will be forcibly removed. In this case, the opening of the smoke channel on the facade of the house is placed according to the instructions for installing gas equipment from the manufacturer, but subject to the following conditions:

at a distance of at least 2 meters from the ground level;
minimum distance to doors, windows and open ventilation grilles(holes) horizontally should be 0.5 meters;
the minimum distance to the upper edge of doors, windows and open ventilation grilles (holes) should also be 0.5 meters;
the vertical distance from the windows located above the opening of the smoke channel - from 1 meter;
in the area of 1.5 meters from the coaxial pipe, there should be no obstacles, say, walls, pillars, etc.

The flue pipe, if there is no condensate trap, must be installed at an angle to the ground, preventing condensation from draining back. The optimum slope is 6–12 °.

If smoke channel placed under a balcony, canopy or eaves of the roof of the house, then it must go beyond the circumference with a radius R. It is equal to the width of the part of the building protruding above the chimney.
The smoke channel should not go through the outer wall into passages (arches), underground passages, tunnels, etc.

When exiting through the wall, the length of the horizontal section of the channel is taken to be no more than 3 meters. However, on this issue, the manufacturing plants allow discrepancies. For example, according to the instructions, the Ferroli coaxial chimney has a maximum permissible pipe length of 4 m (60/100) or 5 m (80/125), and the Navien coaxial chimney - 3 m. the beginning of the design, it is necessary to carefully study the instructions for the gas equipment that is supposed to be installed, since for different boilers some of the basic parameters may not coincide.
(below are SNIP documents, and installation rules for chimneys of some manufacturers)

Coaxial chimneys of the best manufacturers - a guarantee of reliability and quality

Coaxial chimney Ariston
Italian-made Ariston chimneys are suitable for most modern boilers. They also come with them gaskets and wall coverings.

Coaxial chimney Baxi
The chimney in its structure must have a length of up to 5 m. If it is directed towards the street, it is given a slope at the rate of 1 cm for each meter of its length. For the conditions of the Russian climate, insulated options are more suitable with the following changes made to the design:

lengthened head,
the design of the air intake duct is especially protected,
made of composite material.

Such a system makes it possible to prevent icing of the chimney and cause the boiler to shutdown in emergency mode if the outside temperature drops to -50 C.

Coaxial chimney Proterm
These products are very easy to install and help to increase the efficiency of the respective Protherm boilers. In addition to them, the company also offers chimney extensions, adapters designed for separate smoke exhaust and other.

Coaxial chimney Vaillant
This company is considered one of the leaders in the European market. Its products have been in high demand in recent years. When choosing chimney it is especially important that its cross-section matches the section of the Vaillant boiler pipe. During installation, the distance between the chimney and flammable structural elements must be at least 100 mm.

Coaxial chimney Viessmann
In addition to the coaxial outlet (diameter 60/100, 90 °), the kit usually includes: a coaxial pipe equipped with a ferrule (diameter 60/100, length 0.75 m) and wall plates. Its special design prevents the pipe from freezing in winter.