Length of coaxial pipe for a gas boiler. Typical coaxial chimney for a gas boiler - overview of the design and installation diagram

Content

Design and principle of operation
Advantages of coaxial chimneys
Installation and connection to a gas boiler

Introduction

The main feature of gas boilers with closed camera combustion is that they use outside air for combustion. They also need a chimney to release combustion products into the atmosphere. Both of these functions are combined in a unique device - a coaxial chimney for gas boiler.

In this article we will talk about the design, operating principle and advantages of coaxial chimneys, the requirements and regulations governing their installation in private houses and apartments, as well as what you should pay attention to when doing the installation yourself.

Design and principle of operation

Wall-mounted and floor-standing gas boilers are divided into two large groups: with open and closed combustion chamber. The first ones use air from the room to work. That is why, in the place where such a boiler is installed there should be good ventilation. To remove gases, traditional chimneys made of material suitable for working with aggressive environments are used.

Boilers with a closed combustion chamber are completely isolated from the room. Air is supplied to them from the outside, and flue gases are also discharged there. A coaxial chimney is designed to perform both of these functions simultaneously. What is its structure?

Photo 1: Coaxial chimney installation

The term coaxial in technical markings means two-wire. An analogue of the veins in a chimney is made of two pipes of different diameters, inserted into one another. To hold the inner pipe in the center of the outer pipe, they are connected to each other by special spacers. In addition to performing their main function, they also give the structure additional rigidity.

The operating principle of a coaxial chimney is very simple. The gas combustion products are discharged into the environment through the inner pipe, and at the same time, the air necessary for combustion enters the gas boiler through the outer pipe.

Most often, short horizontal coaxial chimneys are used in conjunction with gas boilers. They come out right through the wall country house or ordinary apartment. There is also a vertical structure, which is mounted in the usual way through holes in the ceilings and roof.

Photo 2: Coaxial chimney kit with anti-icing

To combat glaciation horizontal installation, a special design is often used. Its peculiarity is that the pipe for removing combustion products protrudes from the air intake pipe to a considerable distance. Air intake holes are located only in the lower part of the outer pipe, which prevents precipitation from entering inside.

The most common are coaxial chimneys 60/100 with an internal pipe with a diameter of 60 mm and an external pipe with a diameter of 100 mm. Models with such parameters are produced by many manufacturers, such as: Baxi, Vaillant, Buderus, Bosch, Viessmann, Ariston, Ferroli, Electrolux.

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Advantages of coaxial chimneys

Despite its simplicity, the advantages of a coaxial chimney are quite significant. In addition to the obvious advantages of this design, there are a number of advantages that do not immediately come to mind. Let's look at them all in order:

Photo 3: Vaillant 60/100 coaxial chimney system

The combustion chamber is completely isolated, so the boiler does not burn out the air in the room. The entry of carbon monoxide into the living space is also excluded. For this reason, installing a heating device does not require the organization of a special boiler room, such as for example. It can be installed even in a room in an ordinary apartment in a typical multi-story building.
Passing from the outside to the inside, the air is heated by flue gases flowing through the adjacent channel in the opposite direction. Thanks to this, the efficiency of the gas boiler increases.
External walls chimneys have a safe temperature, thanks to the cooling of the central channel by the flow of outside air directed into the system. This increases the fire safety of the system in contact with elements of the building’s cladding and floors.
Installation of a coaxial chimney is very simple. For installation, you do not need to involve expensive specialists and carry out major redevelopment with large-scale construction work. All work can be done by the owner with his own hands.

Despite the apparent simplicity of connecting a gas boiler to a coaxial chimney, during installation some requirements must be met, which are in many ways similar to the rules for installing chimneys with. The safety and efficiency of the entire system depends on their implementation.

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Installation and connection to a gas boiler

As we have already found out, a coaxial chimney can be installed both vertically and horizontally. It is much easier to build a horizontal chimney, however, due to poor natural draft, it is only suitable for those models that are equipped with exhaust fans.

Installation work gas chimneys regulated regulatory documents SNiP SP 42-101-2003. We will list the basic rules and points that should be taken into account when installing coaxial chimneys. Let's start with horizontal structures:

When purchasing a coaxial chimney kit, you should make a choice based on its cross-section. It should not be smaller than the outlet pipe of the gas boiler.
According to the regulated rules for installing chimneys, the length horizontal section should be no more than 3 m. Some manufacturers recommend longer lengths for their models, relying on the increased power of exhaust fans.
The coaxial chimney should be installed at an inclination of 3° per meter of pipe away from the boiler. This is done in order to set the direction for the drainage of the resulting condensate.
When planning a place for a hole in the wall, it should be taken into account that there should be a distance of 0.5-1 m from the boiler outlet to the wall. This is done in order to avoid icing of the chimney inside the room when low temperatures in winter.
When installing a gas boiler near windows, it should be taken into account that the distance from the outer pipe of the coaxial chimney to the nearest window must be at least 0.5 m. It is strongly not recommended to place the pipe under the window. If there is no other possibility, then it should be at least 1 m below the window level. The distance to the gas supply pipe should be at least half the diameter of the coaxial chimney.
To avoid contamination, the external pipe must exit at a distance of at least 2 meters from the ground surface.
If the coaxial chimney is located under a canopy or balcony, then it must have a certain length of the protruding part. How to determine it is shown in the following figure:

Photo 4: Rules for installing a coaxial chimney under a canopy

A vertical coaxial chimney is installed if for some reason it is impossible to install a horizontal one. Installation of such a structure is more complex and is subject to the same requirements as for installing a chimney for a solid fuel heater, such as. We list the main points that are worth paying attention to:

When assembling chimney elbows for a gas boiler, each upper elbow should be inserted inside the previous one and connected with clamps. If this rule is violated, condensate will penetrate through the joints and flow down the outer walls of the chimney.
To collect condensate, ease of cleaning and maintenance, a tee is required to be installed at the bottom of the structure.
Special attention should be given to the section of the coaxial chimney located on the roof. How this part of the chimney should be built is clearly shown in the following figure:

Photo 5: Requirements for installing a coaxial chimney on the roof

Attention: Due to the risk of icing, the installation of protective caps (deflectors) on gas chimney pipes is prohibited.

To see more clearly how to properly install a coaxial chimney, see the following video:

Warmth is one of the components of comfort and coziness in the house. Today there are many ways to heat your home. For multi-apartment buildings, the solution is centralized heating, while owners of private houses have to install boiler equipment.

Such devices that work with fire necessarily require the presence of a smoke exhaust device. And if conventional pipes were previously used, today they have been replaced by a more advanced solution. An increasing number of homeowners are resorting to installing coaxial chimneys, which are efficient.

Coaxial pipe device

A coaxial pipe requires the presence of two nodes, one of which is inserted into the other. The design has two contours, which have different diameters and are arranged according to the principle of a Russian nesting doll. There is a jumper inside that prevents parts from touching.

Such a device is mounted in a heat generator that has a closed combustion chamber; it should include a gas boiler. The coaxial pipe has such a device that the inner pipe is used to remove combustion products to the street, while a larger diameter pipe, which is located outside, is used to supply the oxygen necessary to ensure combustion.

A standard coaxial type chimney has a special device that allows you to solve problems, one of which guarantees the combustion process, the other ensures the flow of air. The length of the device does not exceed 2 m. Typically, such structures are located horizontally and lead out through the wall. Sometimes there is a coaxial pipe that exits through the roof and ceiling.

Problem solving

The design of the described chimney allows it to work on a principle that differs from the usual one. The oxygen necessary for combustion enters the equipment from the outside. This eliminates the need for a constant flow of air into the room using the ventilation method, which is traditional for conventional smoke exhaust ducts. Among other things, several other problems that are characteristic of traditional chimneys are quite successfully solved, among them:

reduction of heat losses;
reducing the risk of fire;
high coefficient useful action;
the combustion process occurs in a closed chamber;
saving space;
Possibility to choose a chimney from a wide range.

More information about the benefits of a chimney for gas boiler equipment

Coaxial pipe allows you to reduce heat losses due to the fact that the air entering from the outside is heated by the exhaust air hot pipe, as a result of which it is possible to achieve a higher efficiency. The risk of fire is minimized, this especially applies to areas that come into contact with the exhaust channel and flammable surfaces, because the inner pipe is cooled to a safe temperature when it transfers heat to the one located outside.

Such chimneys for gas boilers ensure complete combustion of fuel, and unburned particles are not emitted outside and do not pollute the atmosphere. Equipment equipped with a coaxial chimney is environmentally friendly. Due to the fact that processes such as combustion, gas removal and oxygen supply occur in a closed chamber, the operation of the equipment becomes safer for humans, combustion products that could pose a health hazard no longer enter the room. This also indicates that a ventilation system is not required.

Chimneys for gas boilers are quite compact in size, which additionally saves space. By visiting the store, you can find designs that are presented in a wide range; certain models are used for systems of different power.

Installation Requirements

Today there are two known ways in which a coaxial chimney can be installed:

vertical;
horizontal.

The smoke exhaust duct will have a direction that is determined by each boiler individually. It is important to consider that horizontal structures are intended exclusively for those devices that have forced ventilation. If you look at the sanitary norms and rules, you can find out that the horizontal section must have a limited length, its maximum value does not exceed 3 m. But some manufacturers set other restrictions for their products. Therefore, before designing structures, it is necessary to familiarize yourself with the characteristics of the device.

Pipe orientation and connection

The coaxial gas pipe is positioned vertically if it is not possible to arrange the channel outlet through the wall. This case applies to small street widths or close windows. The coaxial chimney can also be oriented obliquely.

Installation work should begin after you can select the correct device. If we take into account the installation standards of the internal chimney, then the diameter of the outlet should not be larger than the diameter of the outlet channel. This point should be checked by checking the data on the chimney passport, where you can find its diameter.

Coaxial pipes for gas boilers are connected to the equipment using a pipe, tee or elbow. Each subsequent element must be fixed to the previous one in such a way that no obstacles are created for the removal of combustion products.

Work methodology

The list of elements that will be required for installation will depend on where the outlet pipe is located - at the top or on the side. In the first case, it is much easier to remove the chimney. For the second option you need to use horizontal design, brought to a vertical position using modifications and brackets.

To install the pipe, you need to use an adapter unit. Clamps are fixed to other elements in a rigid way. Using an adapter or extension cords homemade production, wrapping with tape and applying sealant are unacceptable, because these options will not only be unsafe, but also unreliable.

When installing a chimney, it is important to remember that the outlet pipe must be at least 1.5 m above the heating device. The pipe outlets should have an angle of 3 °, which will ensure unhindered exit of condensate. It is best to place the coaxial chimney 1.5 m above the roof surface, otherwise it may become clogged.

If you plan to equip quite complex system, then the total length should be 3 m. Installation of a coaxial pipe should not involve the presence of more than 2 elbows. A distance of 60 cm should be provided from the nearest windows to the outlet pipe; as for the distance to the gas supply pipes, this parameter should be 1/2 the diameter of the outer pipe. The fragments of the structure must fit together as tightly as possible; if you have to go around obstacles with the chimney, you should use a special elbow with different angles tilt You can use two such nodes at once.

Arrangement of the critical area

The roof area is considered the most critical area; work here must be carried out taking into account fire safety. For this purpose, insulating pipes and non-combustible insulation are used. Between the pipe and the ceiling it is necessary to leave air gap. The smoke exhaust duct should not come into contact with objects; protective covers are used for this.

If the chimney is exhausted through the roof, then this unit must be sealed, protected by an apron that should cover the joint. When the output is through a wall, non-combustible materials must be used. A coaxial chimney should always remain cold; this feature is one of the main ones.

Chimney freezing

Quite often, owners of boiler equipment wonder why the coaxial pipe freezes. In this case, the boiler room may even stop functioning. In order to avoid such a nuisance, it is important when connecting the boiler to try not to ignore the manufacturer’s advice. It is necessary to observe the length of the pipe, its location and slope. The presence of a fan will free the chamber from combustion products; it will provide rarefaction, which is necessary to suck in new air.

Coaxial kits also differ in the material of manufacture, as well as in design, so some of them may freeze, while others function normally. If the vertical coaxial pipe is frozen, the problem can be partially solved by removing the plugs that are located in the upper part of the boiler. In this case, the flue gases will go outside, and the air will come from the room.

The plug should be installed in its original place as soon as the ice melts. After all, the boiler will not be able to operate in this mode all the time. Unit breakdown is inevitable if airborne particles such as kitchen dust and soot get into the equipment. When icing does not happen so often, this method can be used, but if freezing occurs regularly, you should purchase an anti-ice kit.

Conclusion

You can purchase a 60/100 coaxial pipe for RUB 1,500. It is an active design that can improve the environmental characteristics of the boiler and its fire protection properties, while simultaneously increasing operating efficiency. You can do the installation yourself, but if you doubt your abilities, it is better to entrust the installation to professionals.

One of the most effective means to heat the house is a heating system connected to a gas boiler. Boilers using gas as fuel warm up quickly enough, maintain temperature well and are inexpensive to operate. In addition, a good gas boiler often also provides water heating, which is very convenient and profitable.

An important component heating system The pipe that allows the boiler to operate is a pipe that discharges combustion products into the atmosphere. The removal of combustion products can be carried out by coaxial pipes for gas boilers, which will be discussed in this article.

Problems with conventional chimneys

As mentioned above, one of the main problems that arise when using gas heating equipment is the removal of combustion products from the system. This is a serious drawback, and most other heat sources do not have this quality - but here you have to take care of removing carbon dioxide and carbon monoxide.

To remove these substances, chimneys are used, which may have different designs and be created from different materials - metal, ceramics, brick and many others. The installation and characteristics of a chimney directly depend on its purpose, design features and other parameters.

All chimneys that fit this description, in addition to their advantages, also have a lot of disadvantages. Firstly, it is worth noting the problem associated with the exhaust and supply of air through one pipe - sometimes this leads to deterioration in the operation of the system. However, this problem seems insignificant compared to the next one.

Secondly, any chimney becomes clogged over time, as a result of which the draft in the boiler becomes much worse. If you leave a clogged chimney for a gas water heater in an apartment without attention, then at some point it will become completely clogged and the heating system will stop working. In addition to stopping the heating, a clogged chimney also threatens that gas combustion products will enter the living space - and this should not be allowed under any circumstances.

Installing a coaxial pipe for a gas boiler as a solution

The problems described above are quite unpleasant, but technology does not stand still, and construction industry was no exception - coaxial pipes began to be used as chimneys. A coaxial pipe is a structure that includes two pipes, one of which is located outside, and the second, respectively, inside.

The inner tube has a smaller diameter - the standard value is usually about 60 mm. However, sometimes a larger diameter of the coaxial pipe for a gas boiler is selected. It will not be possible to use a pipe with a diameter of less than 60 mm as a chimney - such a cross-section is not enough to effectively remove combustion products. In addition, the small diameter of the chimney often causes complete clogging with various deposits, even taking into account the low susceptibility of the coaxial pipe to this factor.

The outer pipe has a larger diameter - the average value for a 60 mm inner pipe is 100 mm. Simple calculations allow us to say that the dimensions of the pipes are in a ratio of 1:1.5. A pipe with a diameter of 100 mm ensures a continuous supply of air to the boiler. Besides, outer shell necessary to drain condensate that is released on the inner pipe.

Regardless of the selected sizes of coaxial pipes (and their configuration may differ significantly from standard values), installation of the coaxial pipe of a double-circuit gas boiler is carried out using clamps and special fasteners. During installation, it is necessary to ensure that there is no direct contact between the two pipes - in fact, the coaxial nature of the structure implies the presence of a biaxial mechanism.

Advantages and disadvantages of such a solution

Coaxial pipes in combination with gas heating equipment ensure high-quality operation of the entire system. This is largely due to the positive qualities inherent in the type of chimney in question.

The main advantages of coaxial pipes are as follows:

Significant increase in the efficiency of the heating system;
Safe and permanent removal of combustion products;
Good protection of the structure from clogging;
Condensate is removed from the system through a safe circuit, and through separate pipe air enters the system;
Low probability of problems occurring;
Simplicity of design with high efficiency.

All these advantages together seriously increase the efficiency of the system as a whole. For example, constant supply fresh air through the external pipe it provides the system with the oxygen necessary for combustion. Condensation is also retained on the outer pipe and gradually dries, so the inside of the system is protected.

The condensate aspect is very important - most of the internal damage to the system is caused by it. As a result of the release of condensate and the accompanying oxidation processes, solid deposits appear on the surface of the pipe, which subsequently must be cleaned. The use of a coaxial pipe with its special characteristics makes cleaning the structure much easier.

However, coaxial pipes also have several disadvantages, including:

High cost of materials;
Standardization of pipes does not allow the creation of individual configurations;
Installing a coaxial chimney is very difficult to do on your own;
During installation, it is necessary to comply with a number of safety requirements, which is not always possible to do.

Requirements for installation of coaxial pipes

To realize everything positive traits coaxial chimney, the following requirements must be met:

The slope of the pipe from the axis should be about 3 degrees. This requirement will allow the system to independently remove condensate from the pipe. Otherwise, moisture removal will occur too slowly, resulting in the system becoming clogged and unable to perform its functions.
The pipe outlet should be located at a height of 1.5 meters from the ground and at a distance of 0.6 m from the nearest window.
During installation individual elements designs, it is necessary to use fittings, avoiding various handicraft methods of connecting pipes. In addition, it is undesirable to bend the pipe more than three times - an excessive number of turns reduces the strength of the structure.
The length of the coaxial pipe for a gas boiler can only be increased with the help of special sealants or mastics purchased from pipe manufacturers. Inappropriate materials may cause damage to the integrity of the chimney.

Installation of a coaxial pipe of a gas boiler, carried out in compliance with these requirements, will allow you to assemble a reliable and high-quality structure.

Installation of coaxial pipe

Installing a coaxial pipe for a gas boiler falls into the category of complex processes - the design is not simple, and the requirements for it are quite serious. In addition, you need to think in advance about how to install the pipe according to the simplest possible scheme, so as not to complicate the already problematic installation.

The process of installing pipes for different boilers is practically the same. For example, you can take a standard chimney, which includes pipes with a diameter of 100 and 60 mm (external and internal pipes, respectively).

The installation algorithm for coaxial pipes is as follows:

First you need to prepare all the equipment and design the future structure.
In all ceilings and obstacles through which the pipe will pass, it is necessary to drill holes, the size of which should be 10 mm larger than the diameter of the outer pipe. A 10mm tolerance is required to install the fasteners.
The base is connected to the boiler outlet. Most boilers have the outlet on the top, so there shouldn't be any problems.
Next, the lower part of the pipe is installed. Its fixation is carried out using clamps and fittings.
After installing the first section, you can begin installing the remaining elements of the coaxial chimney.
The pipe connections must be treated with sealant or similar material.
Final stage– checking the system for operability, for which you need to conduct a test run.

The pipes must be connected tightly and efficiently - its operation depends on how well the sections of the chimney are joined. The outer and inner pipes must be located on the same vertical axis and strictly parallel to each other - any contacts are unacceptable. As practice shows, a small displacement occurs during operation, but it is insignificant and does not affect the performance of the system.

It is best to keep the number of fittings and elbows to a minimum. According to the requirements, 3 fittings or 2 elbows can be installed on a three-meter piece of pipe, but this is the maximum allowable number - the fewer different connections there are, the more reliable the structure will be.

Conclusion

Installing a coaxial pipe for a gas boiler is quite complicated, but in the future it pays off in the efficiency of the heating equipment. When designing and installing, it is necessary to take into account all the nuances and approach the work with all care in order to create the most reliable and high-quality design.

Do-it-yourself installation of a coaxial chimney for a gas boiler is often done to optimize the functioning of the heating system. If it does not run on electricity, then mandatory requires smoke removal. Previously, standard chimneys were used for this, but today more advanced devices have appeared.

What is a coaxial chimney

Construction involves placing one object inside another. A similar chimney is made in the form of a double-circuit product. Pipes of different diameters are used as building materials. Such “structures” are divided into several types:

External and internal. Devices are divided into these categories depending on their location. The first type is placed outside the building and fixed with special brackets directly to the facade. Distinctive feature appearance is convenience during installation and use. Internal types chimneys are installed in pre-prepared shafts. This type is quite difficult to install and maintain; moreover, strict adherence to safety precautions is required.
Uninsulated and insulated. The second option is useful in the cold season, when the channel responsible for entering the system air masses, freezes with a high degree of probability. This leads to a reduction in the supply of oxygen to the combustion chamber, which reduces the efficiency of heating equipment. Insulated systems are able to ensure the functioning of the boiler even at extremely low temperatures. This type differs from a conventional chimney in the presence of an additional pipe, and the system consists of elements nested within each other. The space is filled with any type of insulation.
Collective and individual. The second type is used when it comes to servicing one boiler. She represents simple design no branches. When it is necessary to ensure the removal of combustion products generated during the operation of several heating units, a collective type of chimney is used. It is a mine system with several branches.

Each of the described varieties has its own characteristics and scope. Before installing one type or another, it is recommended to study in detail all the information about them.

Components for a coaxial chimney can be purchased in specialized stores

Design and principle of operation

The design of such a device allows it to perform several functions, that is, to provide a stable flow of oxygen to “stimulate” the flame in the firebox and remove smoke. The device includes several modules, which include:

Straight pipes. They are used to construct the main building.
Decorative linings, which are flanges that cover the places where the chimney trunk passes through building structures.
Tees that become part of the system if combustion products need to be removed from several heating units at once.
Seals (are devices that ensure complete tightness of the housing at the points of passage through the wall).
Connecting devices. They are 90° and 45° bends or couplings.
Reinforcing elements, which include clamps and brackets.
Devices designed to remove condensate. This structural element is located on vertical sections and is equipped with a water shutter that does not allow air pressure to decrease.
Adapters. They are needed to connect the chimney system to the boiler.
Components equipped with a special hole. Such a “viewing window” is needed to diagnose and remove contaminants from the chimney.
Nozzles They are needed for the timely removal of smoky masses and air intake from the street.

Functioning consists of external intake of air masses from the street through an external channel. While moving through the pipeline, the air is heated due to contact with the channel inside a special shaft for “transporting” smoke masses. Heated oxygen enters the firebox, which increases efficiency and reduces costs gas fuel during boiler operation.

It is important! The channel on the outside plays the role of a cooling device that lowers the temperature on the surface of the pipeline. Thanks to this, a chimney of this type can be installed in a private (wooden) building without adopting serious measures on ensuring safety (fire).

As mentioned above, the internal channel provides “transportation” of smoke masses. It is often equipped with special insulation, which makes it possible to increase traction in vertical structures. This type has three channels, one of them is intended for filling with basalt-based insulation. To ensure the uninterrupted operation of a homemade chimney, it is necessary to make calculations in advance and carry out the installation efficiently, taking into account the structural features.

Chimney installation diagram

Advantages and disadvantages

The main advantage of the coaxial type chimney exhaust is that the air masses used in the operation of the boiler are taken not from the room, but from open air. This eliminates the need to create a powerful ventilation system; moreover, even a small room is suitable for use as a boiler room in such a situation.

In addition to the described feature, positive aspects Similar devices include:

High installation speed. The design of the chimney cannot be called complex, so installation can be done independently (it is not necessary to involve specialists and pay for their services).
Possibility of use for removal of combustion products from the boiler room apartment building.
Possibility of use to increase the operating efficiency of almost any type of heating equipment.
A good indicator of traction, which is observed if the installation work is done efficiently.

Thanks to the listed positive aspects, the coaxial chimney is popular among large quantity of people. In addition to the advantages, two-channel chimneys have a number of disadvantages.

These include:

The need to coordinate installation with the sanitary and epidemiological inspection service. This is due to the fact that during operation a lot of toxic condensate is released. Pouring this substance onto the ground is strictly prohibited, and disposal must be done in specially designated areas. However, if you use this type of chimney in a private house, then all claims will be reduced to the individual wishes of its owners. But when installing collective systems, obtaining permission from the service mentioned above is a prerequisite.
The need to organize pipe insulation from coaxial condensate. Even small errors made during installation will lead to icing of the outlet, which will cause a decrease in traction.

Despite the described disadvantages, chimney systems of this type are often installed both in private houses, cottages or dachas, and in multi-apartment buildings. However, the installation procedure must be treated with maximum responsibility and attention. This will help avoid extra expenses in future.

Moreover, installation errors can lead to deformation of the chimney pipes during operation. Some problems can be solved by specialists, but if problems are ignored for a long time, it may be necessary to purchase a new system and install it.

The diagram clearly shows how a coaxial chimney works

Do-it-yourself installation of a coaxial chimney for a gas boiler

There is nothing complicated in the installation algorithm, but there are features that have a significant impact on the functioning of the system in the future. Before purchasing a ready-made chimney system, you need to carefully study the diameter of the pipeline that will connect to the boiler.

It is important! SNiP requirements play an important role in installation and further operation. Their observance is prerequisite, since neglect of such rules can lead not only to problems with sanitary and epidemiological supervision, but also to accidents.

Regulatory requirements SNiP

The rules for installing chimneys for a gas boiler, as well as the relevant standards established by the state, are described in detail in SNiP 2.04.08-87 and 2.04.05-91. Drawing up individual projects, calculation procedures and installation are carried out in accordance with them. Violation of these rules will lead to failure of the gas service and will make legal installation impossible. SNiP is regulated by:

Placement of the chimney on the facade. The head should be located at least two meters from the ground. The size of the hole in the wall should be 1 cm larger than the diameter of the chimney for a brick wall and 5 cm for a wooden wall.
Service. It should be carried out at the beginning and end of the heating season. It is necessary to remove condensation and check joints for leaks.
The use of such systems in MKD. The structure should be mounted at least half a meter from the door and window openings. There should be at least 1 m to the window above the pipe.
Installation. The chimney pipe must be at least 30 cm from the wall. If we are talking about turbocharged boilers - from 1 m. A constricting diaphragm must be installed, which is required to limit the flow of air into the closed combustion chamber.
Norms fire safety. The minimum gap between the chimney pipe and wooden wall should be 5 cm. This is due to the fact that during operation the outer surface is practically not subject to heating. Non-combustible materials must be placed between the wall and the pipeline. The best option is basalt insulation. The chimney pipe must be located at least 1.5 m from the windows and doors of neighboring houses. There should be no pillars, trees or other objects in this gap. It is prohibited to use a standard chimney to remove combustion products (only coaxial varieties).
Restrictions on output through the facade. The ban on draining condensate onto the ground must be observed. Therefore, the pipeline must be installed at an angle to the boiler. If the design includes a special device designed to drain condensate, then a slope of the outlet pipe towards the ground is allowed (for the purpose of draining rainwater). If we are talking about using a collective type of chimney, then issues of condensate disposal must be coordinated with the sanitary and epidemiological inspection service.
Features of each type of chimney system. It can be horizontal or vertical. It is strictly prohibited to connect to the same network of chimneys with forced and natural types of removal of combustion products.
Features of laying a horizontal section. Laying through an adjacent room not intended for human habitation is allowed if the length of the pipeline section that will pass through it does not exceed 3 m. If we are talking about a turbocharged system with forced removal of combustion products, then it is allowed to increase the section of pipe passing through the non-residential premises , up to 5 m.

The described safety requirements may change over time, therefore, before starting installation work, it is necessary to obtain specialist advice.

Requirements of sanitary standards and rules for distances between objects

We carry out the installation

If you need to install the chimney yourself internal variety, then all actions are performed in the following sequence:

Check that the dimensions of the boiler pipe and the chimney pipe match.
Prepare a hole through which the pipeline will be led out. Its diameter must be made slightly larger than that of the pipeline.
Connect the corresponding element of the smoke exhaust system to the gas boiler pipe.
Secure the connection with bolts and clamps.
Consistently assemble the entire chimney system. Each element is installed in its “own” place, after which it is secured with clamps (they increase the level of reliability of the connection).
Install overlays on top of the fastenings to perform decorative functions. They will help maintain the aesthetic appearance of the structure.
Bring the chimney pipe outside.
Ensure the joint is tight.
Place a casing on the pipe that has protective properties. This will help improve the safety level of uncontrolled fires.

After completing the described installation process, you need to check the tightness of the joints and cover them with a special apron.

If we are talking about an external type of chimney exhaust system, then the installation procedure has its own characteristics. When it is necessary to install such a chimney, you must adhere to the following algorithm:

Determine the exit location and mark its location on the wall of the building.
Make a hole where the mark is. The diameter must correspond to the cross-section of the pipe.
Connect the chimney to heating device. To do this, you need to use a double-circuit elbow and a special tee. It is needed to ensure stability finished design in a vertical position.
Secure the “structure” to the wall using brackets.
Seal the area where the chimney exits the wall and continue to assemble it to the desired height.
Secure the structure to external wall using clamps.

To ensure a reliable connection of double-circuit pipes, it is necessary to use adapter units.

Transition units connecting double-circuit pipes - important elements device design

Features of horizontal and vertical installation

If we are talking about horizontal version installation, then this procedure must be carried out taking into account technical features building. You need to calculate the following parameters in advance:

Pipe height. The distance from the outlet pipe to the hole in the wall should be less than 1 m. Direct pipe outlet from the outlet pipe to the street is not allowed.
Number of rotary couplings (less than three).
The maximum length of the horizontal section. Should not exceed 3 – 5 m.

An increase in condensate production is a feature of the operation of the chimney system during the cold season. Excessive moisture loss is caused by harsh operating conditions.

When it is necessary to install a vertical chimney, you must remember that this procedure can be carried out in two ways:

Cascading. It involves connecting several heating units to one pipe at once. A similar scheme is quite often used in MKD.
Individual. Maximum length vertical elements is 7 m. This allows installation in a two-story private house.

Options for installing a chimney in a private house

If we are talking about a brick building, then the smoke exhaust system can be installed both inside and outside. However, effective thermal insulation is required in any case. This will allow you to avoid unpleasant consequences that are likely to arise during intensive use of the boiler if the insulation is neglected.

Video: options for connecting a coaxial chimney to gas boilers

Installing a chimney is a procedure that can be performed by any resident of a private or apartment building who has basic skills and knowledge in the relevant field. If these are completely absent, then contacting specialists in the installation of such systems is the best solution. This approach will help avoid unnecessary costs, as well as problems with certain services associated with errors made during installation and their consequences that manifest themselves during intensive use.

Question autonomous heating will be decided on an individual basis. Gas boilers with a coaxial chimney are very popular due to their excellent efficiency, availability of fuel and reasonable cost. The main advantage of such a system is the possibility of installation after the house has been built. This article will discuss how to install a coaxial boiler.

The installation of equipment can be entrusted to specialized companies that will carry out turnkey work. Thus, saving owners from coordinating documentation with competent organizations and installation nuances.

However, if you wish to carry out installation work on our own, then knowing the principle of operation gas equipment and observing all the rules and regulations (SNiP), it will be possible to cope with this process without any special difficulties.

Single-circuit coaxial boiler

Operating principle of a coaxial boiler

The coolant, usually water, enters the heat exchanger, where it is heated to desired temperature due to gas combustion. The device has 2 igniters (main and additional, used to maintain the “sleep” mode). Ignition can be manual or automatic.
The equipment is divided into single-circuit and double-circuit. In the first case, the models are intended only for connecting a heating system. Gas units with two circuits provide not only heat in the house, but also heat water for domestic and economic needs.
The combustion chamber is isolated from external influences. The influx of air masses from the street and the exit of carbon dioxide (combustion products) is carried out through a coaxial channel. Its pipe-in-pipe design does not allow mixing of two different flows.

Basically, all units are equipped with control and safety systems. Automation consists of thermostats, indicators, reset and safety valves, sensors, fans, etc.

Types of coaxial heating boilers

Boilers differ not only in technical specifications, but also by installation methods. They are floor and wall mounted. The latter type is much lighter and does not take up much usable space.
With compact dimensions, the power of the equipment is correspondingly reduced. Its installation is carried out for heating greenhouses, office and residential premises with an area of up to 150-250 sq.m.
The floor-standing coaxial boiler differs due to its large combustion chamber high coefficient useful action. Such models are suitable for heating and providing hot water buildings industrial purposes and large residential buildings.

For the manufacture of cases they use various metals and their alloys. The most popular devices are made of cast iron and steel. Such products are characterized by good performance at an affordable cost.
Copper and silumin boilers are distinguished by their high reliability, heat transfer and long service life. However, their cost stops many consumers from purchasing them.

Nuances of choice

To select equipment, it is better to consult with specialists; it would not be a bad idea to ask the opinions of neighbors or relatives who operate such devices.

Their disinterest will help to give a more objective assessment of the boiler’s operation, to note the absence of one or another function, or, on the contrary, to emphasize a wide range, half of which is not necessary to use.

As a rule, devices have a combined operating mode - gas and electricity. When purchasing, give preference to non-volatile models, otherwise you will have a hard time if there is a power outage. The equipment can be equipped with a source uninterruptible power supply. The power of modern UPS is 200-350 kW/h.

IN general outline the plan will consist of the following points:

obtain permission for installation from the gas service;
based on the project, prepare a place for installation of equipment and chimney wiring;
choosing a boiler by power, size, brand, appearance and other parameters.

Consumption of natural or liquefied gas determines the performance of the unit. As a rule, for every 10 sq.m. area consumes 1 kW/h. It follows from this that for a building of 100 sq.m. You need a device of at least 10 kW. Thus, a device with a minimum power of 10 kW/h consumes 1.12 cubic meters. natural gas or 0.86 kg/h liquefied propane-butane.

Country of origin of coaxial gas boilers

As for the manufacturer, the leading places are occupied by factories Sweden and Germany. Their products are characterized by reliability, quality and functionality. High positions are supported by an equally high cost.

Italian boilers have stable quality without complaints. However, positive recommendations are given only for devices assembled in this country. Chinese assembly reduces all advantages to zero.

Equipment from Czech Republic quite unpretentious. However, their weak point is electronics, which is especially important to keep in mind, because instability of the voltage supply in electrical networks is typical for our country. The solution may be to install a stabilizer.
TO budget options relate boilers of domestic, Korean and Chinese production. This category can be called " Lucky case", that is, you can buy a cheap boiler that will surprisingly last long years or, what happens more often, a breakdown will occur in the midst of the first heating season.

Requirements for installing a coaxial boiler

When choosing a location for placing gas coaxial equipment, it is necessary that it meets the following requirements:

Availability ventilation system and gas analyzer;

When installing a suspended heat generator, the wall is insulated with non-combustible material;
installation of floor models is carried out on a concrete base or metal sheet;
It is prohibited to place other gas appliances and electrical equipment closer than 30 cm to the main boiler.

If you comply with the above norms and rules, you can count not only on effective work systems, but also the safety of all family members.

Attention: when installing a boiler with an open firebox, the requirements are more stringent!

Coaxial chimney

Boilers with a closed combustion chamber are installed much more often compared to other types of heating equipment. Their main advantage is the possibility of installation in rooms not equipped with special stationary hoods. For the heat generator to work, a coaxial channel is required, which is discharged through a window or technological hole in the wall.
Equipment of this design can be installed in attics, kitchens and basements. Here, only one condition is necessary - the presence of a window or the ability to drill through the wall for the chimney pipe to exit.
The design consists of two pipes different sections, inserted into each other. Combustion products exit through the inner pipe. The distance obtained by the difference in diameters is used to draw in fresh air masses.

The features and advantages of a coaxial chimney include:

the flow of air with the simultaneous removal of combustion products provides protection against the entry of carbon monoxide into the room;
the special design does not allow heating the outer casing of the pipes, which means it does not transfer heat to the walls, which is not safe for wooden buildings;
This system increases the efficiency of the entire heating system of the house as a whole, by partially heating the street air.

Channels are purchased separately from the boiler, big choice provides the opportunity to select products not only of the required diameter, but also of the preferred material (polymers, ceramics, galvanized steel, etc.). Sometimes pipes are included with the gas device.

Installation of coaxial boilers

The installation of equipment is carried out no closer than 60 cm from the window opening; such standards are determined by the fact that the exiting carbon monoxide didn't come back. If such conditions do not exist, use the maximum possible distance.

Floor boiler. This unit requires a level base. A technological gap is left between the rear wall of the housing and the wall of the building for servicing the device. Having placed the unit in the intended location, assemble the coaxial system. Then mark its exit point on the wall with minimum distance 1.5 m from the floor.
Wall-mounted boiler. Installation of this type of device is carried out on a load-bearing or reinforced wall. Estimate at what height it will be convenient to service it, the optimal parameter is 1-1.6 m. At this level, mark the points for the bar (it is included in the kit). Check the levelness with a building level.

Place the boiler on the mounting strip. Next, you need to assemble the chimney duct and determine where to drill a hole for the pipe. Here it should be taken into account that with a horizontal outlet of the channel, the slope must be at least 3 degrees. This will greatly facilitate the drainage of condensate.

Chimney hole

After moving or removing the equipment, use a hammer drill with a special attachment to drill a hole required diameter. The pipe must pass freely into it. The crown is selected depending on the material from which the walls are built (wood, brick, concrete blocks).
There is no need to worry about the interior and exterior. Special decorative overlays are available for sale.

Assembly of coaxial pipes

Each specific case determines the direction of the channel. This can be inclined, vertical or horizontal.

Advice: horizontal movement of the system is only possible with forced ventilation!

The vertical direction is more often used when it is not possible to make a channel exit through the wall. In this case, it is necessary to calculate the path of the channel through the roof so that the pipe does not rest against joists or other structural parts of the roof.

For the chimney, use factory-made fittings and components. With their help, assembly and installation will be better and more reliable. Try to avoid numerous bends and turns.
Maximum simple form channel will work more efficiently. When extending the channel, but not more than 3 m, special clamps are used.

Advice: it is prohibited to use sealant or any other available materials.

Assembly of the entire system

The final assembly of all system elements begins with the installation of gas equipment in place. The boiler is connected to the gas supply. A special rubber hose is used for this. The tightness of the connections is checked by wetting them with a soap solution.
An adapter is used to connect the pipe to the equipment. Next comes a vertical extension, a connecting clamp, and then an elbow for horizontal rotation of the channel. You can immediately use the elbow after the adapter.
A pipe of the required length is connected to the elbow, followed by a discharge channel. The distance must be calculated so that this element protrudes onto the street by at least 30 cm.
For horizontal drainage, a condenser collector is required. It is mounted at the bottom of the structure.
Now all that remains is to connect the boiler flare to the water supply system.

Before work, contact the authorized bodies to obtain permission to install and operate heating equipment. The ease of installation of the boiler itself and the coaxial chimney should not be misleading. Only by adhering to the attached instructions and observing the requirements of SNiP can we talk about the quality of heating of the premises and the safety of all residents.