Attached chimney for a gas boiler. Chimney for a gas boiler in a private house: selection criteria, prices

Content

When arranging a heating system, special attention should be paid to the installation of a channel through which combustion products are discharged into the external environment. A chimney for a gas boiler in a private house requires competent selection of materials, pipe manufacturing, project development taking into account all the requirements of SNiP, compliance with the construction installation technology. Errors at any of the stages will result in a decrease in the efficiency of the boiler and, accordingly, unnecessary energy costs, an increase in emissions into the atmosphere. Alteration of the chimney is a laborious and costly undertaking.

Chimney pipe for gas boiler

Basic requirements for the installation of chimneys

The design and installation of a chimney for a gas-fired boiler unit must be carried out in accordance with the standards in force in Russia. Violation of the installation and operation rules is dangerous for human life and health.

For the installation of heating equipment, a separate building is usually allocated, a room is equipped in the basement or on the first floor of the house. The boiler room is equipped with a chimney in accordance with the standards prescribed in the acts of SNiP 2.04.05-91. The chimney structure must:

• Provide draft that allows you to effectively remove exhaust gases and maintain the boiler efficiency at the required level.
• Withstand prolonged heating to high temperatures.
• Have fully sealed joints of the constituent elements.
• To be integral in places of passage through the roof, walls, ceilings.
• Have a condensate collector (this element is designed to collect and remove liquid from the system).
• Have no more than three turns throughout.
• Be equipped with inspection hatches at all corners, as they are places where soot accumulates.
• Have a length of horizontal branches of not more than one meter (if any);
• Rise above the roof to provide the necessary draft intensity and eliminate the risk of reverse draft when combustion products enter the room through an open combustion chamber.
• Placed at a distance of 5 cm or more from structures with a non-combustible surface and at least 25 cm from combustible materials.

The chimney is installed in accordance with SNiP 2.04.05-91

The size of the internal section of the chimney must not be less than the diameter of the flue pipe of the boiler unit. If two devices are planned to be connected to the chimney, its cross section must be increased with the expectation of simultaneous operation of both units and be the total size of the cross sections of the nozzles.

Chimney: principles for choosing materials

Requirements for chimneys make you carefully consider the choice of material from which it will be mounted. When choosing a material, you should focus on the type of energy carrier that you plan to use to heat your home. Consider:

• Flue gas temperature (the material must have a thermal stability margin relative to the standard flue gas temperature of the selected fuel).
• Corrosion resistance (combustion products contain aggressive substances).
• Tendency to form condensate in the chimney.
• Pressure inside the chimney (the chimney can be designed for natural draft or turbocharging).
• Resistance to ignition of soot deposits on the inner walls (for a short time the temperature can reach +1000 ° C).

If a gas boiler is used as a heat source, then for its manufacture a material is required that is designed for continuous heating up to +200 ° C and short-term heating up to +400 ° C. Since sulfuric and hydrochloric acid are not formed during the combustion of natural and liquefied gas, materials belonging to the first class in terms of corrosion resistance can be used.

Consider what materials are popular for arranging chimneys for gas boilers.

Brick

Brick is a classic option for building a chimney, but today modern design solutions compete with it. A brick chimney is located inside the building, passing through the floors and roof. Structural sections that are located in unheated rooms or on the outside of the building require high-quality insulation to prevent flue gases from cooling. To make a brick chimney, use red brick (solid, M150 and above), lime or lime-cement mortar.

Types of brick chimney

Brick pipes compare favorably:

• high heat resistance (withstand heating up to +800 °C);
• fire safety;
• durability;
• aesthetic appearance.

But for a gas boiler, a brick chimney is not the best solution.. Due to the relatively low temperature of the exhaust gases, condensation will form on the inner walls of the flue duct. Moisture can appear on the outer surface of the pipe, destroy the brick. To compensate for this drawback, a brick chimney is mounted from steel or ceramics, which are not afraid of condensate.

Seeping condensate on the wall of the building

The disadvantages of bricks include the roughness of the surface, which is why such pipes quickly overgrow with soot and need regular cleaning to prevent it from catching fire. Due to overgrowth, there is also a decrease in the intensity of traction. Another disadvantage is the large weight of the structure, it needs a special foundation, which adds labor intensity to the work and increases installation costs.

Stainless steel

The flue system for a gas boiler can be made of heat-resistant stainless steel, resistant to aggressive environments. Such material with a thickness of 0.6 mm is designed for heating up to +500 °C. To install such a chimney, they use ready-made pipes and fittings - bends, tees, adapters, etc. The system can be used as a stand-alone chimney or installed inside an existing brick channel.

Stainless steel flue

The advantages of stainless steel chimney structures include:

• simple and quick installation due to the low weight and design of the elements, no need for a foundation;
• maintainability - the damaged area is quite easy to replace;
• smoothness of the inner surface - soot layers do not settle on it, narrowing the working section of the chimney and reducing draft, the channel is easily cleaned, there is no risk of soot igniting;
• corrosion resistance;
• the ability to install complex systems;
• tightness of the joints of the elements, which allows the use of pipes to create a forced exhaust of combustion products.

The disadvantages of steel chimneys include the high cost of structural elements compared to brick or ceramic options. Relatively low heat resistance is critical for solid fuel boilers, and for gas units this indicator is sufficient.

The structure of the sandwich pipe

There are several types of steel chimneys. The choice depends on the operating conditions, climatic features, boiler design. To equip the chimney channel, you can use:

• Single-wall pipes with a round section. Bent from stainless steel sheet, they are the most affordable option. They are usually used as a sleeve inside a brick channel or mounted in a bathhouse and equipped with a water jacket to use the thermal energy of the flue gases to heat the water in the shower.
• Single wall pipes with oval section. They are used for lining an existing brick chimney with a section in the form of an elongated rectangle.
• Sandwich pipes. This is a double-walled structure, equipped with a heat-insulating non-combustible layer of basalt wool between the inner and outer pipes. This option reduces the risk of condensation on the inner surface and prevents heating of the outer pipe. Such a chimney is easy to assemble, fireproof and suitable for installation inside and outside the house.
• coaxial chimney. It also consists of an inner and outer pipe with a gap between them, but differs in functionality. The inner pipe serves to remove flue gases, and the annular space around it is a channel for air to enter the closed combustion chamber of the gas boiler.

Ceramics

Manufacturers offer ceramic pipes of round and rectangular cross-section. A ceramic chimney needs a special shell to protect it from external damage and reduce the amount of condensate by keeping the heat of the flue gases.

The shell for ceramic pipes is a special design made of hollow concrete blocks or a ready-made brick chimney. A non-combustible thermal insulation material - basalt wool - is laid between the pipe and the shell. Since ceramics tend to absorb moisture (it appears on the walls of the chimney as a result of condensation of cooled flue gases), vertical ventilation channels are left between the insulation layer and the outer shell. The outer section of the chimney must be reinforced with steel rods.

Ceramic chimney

Ceramic chimneys equipped with a steel body are relatively light in weight and do not need a foundation, unlike floor structures made of brick or concrete blocks.

The advantages of ceramic pipes include:

• chemical inertness and corrosion resistance;
• smoothness of the inner surface (does not allow soot to settle, simplifies cleaning of the smoke channel);
• high ability to retain heat (reduces the intensity of condensation);
• durability.

Depending on the material, a ceramic chimney can withstand temperatures up to +650 °C or +450 °C. For gas stakes, the second option is sufficient, since the temperature of the exhaust gases is relatively low.

Asbestos-cement pipes

Asbestos-cement pipes, due to their availability, have been actively used for chimneys for a long time. The advantages of the material can be attributed only to low cost, since:

• the maximum heating temperature of asbestos cement is +300 ° C, which is not always sufficient for the safe operation of the chimney (it is not recommended to place the asbestos-cement pipe close to the furnace, therefore, the lower part of the chimney channel is often made of bricks);
• the roughness of the inner surface contributes to the settling of soot - such a pipe must be cleaned regularly to prevent soot from igniting, since asbestos cement can explode from sudden heating to high temperatures;
• the material is unstable to aggressive environments and absorbs moisture, due to which condensate destroys the pipe over time;
• asbestos cement pipes are quite heavy, which complicates installation;
• the joints of the elements are difficult to make airtight.

Chimney channel from asbestos-cement pipe

The use of an asbestos-cement pipe for gas boilers is possible, but subject to high-quality installation and arrangement of a thermal protective casing, which increases costs and increases the complexity of the work. Given the need for an asbestos-cement chimney for frequent maintenance, preference should be given to other, more practical materials.

Chimneys for units with an open combustion chamber

A chimney gas boiler is a unit equipped with an atmospheric burner. It takes oxygen from the air in the room and removes the products of combustion through the chimney. To ensure intensive movement of gases (draught), the chimney must be vertical (with a minimum number of horizontal or inclined sections, ideally without them) and have a smooth inner surface. The room where the boiler with an open combustion chamber is installed needs good ventilation. Without sufficient traction, the efficiency of the unit decreases and the risk of combustion products entering the room increases.

Installation options for chimneys for a floor-standing gas boiler include:

• removing the pipe through the wall to the outside and then vertically upwards to the required height (external or attached chimney);
• installation of a vertical pipe that passes through the ceiling and roof (to take the pipe away from the wall, you can mount two elbows with an inclination angle of 45 degrees, since bends at a right angle will become places of intense accumulation of soot and worsen traction).

Chimney with atmospheric burner

Installation of an attached chimney for a wall-mounted boiler is technically easier to perform. It is important to properly equip the penetration through the wall, observing the size of the fire gap, if the wall structure is made of combustible materials. The external exhaust duct needs high-quality insulation, as the rapid cooling of flue gases reduces draft and provokes increased condensation. To prevent the structure from being torn off by the wind, it must be securely attached to the wall. The regulations require that a tee with an inspection hatch and a condensate trap be installed at the bottom of the chimney.

The main difficulty in installing an internal chimney is the arrangement of passage units through the ceiling and roof. If a steel system is being installed, special “passages” are installed; a gap filled with basalt wool is provided around the walls of the channel made of concrete blocks or bricks.

Features of the assembly of steel pipes

The scheme for assembling external chimney channels from steel single-walled or sandwich pipes provides for the arrangement of sealed joints, on the inside of which condensate will not accumulate - for this, the upper pipe is inserted into the lower one with a corrugated edge (assembly "by condensate").

Pipe assembly for smoke and condensate

If the pipe passes inside the house, it is more important to prevent the penetration of combustion products into the room, so the pipes are unfolded and the upper element is put on the lower one with a corrugated edge (smoke assembly).

The configuration of the sandwich pipes allows you to make a chimney with a double circuit, internal and external, collecting one of them "by smoke" and the second - "by condensate". This is the most difficult of the options, but the most reliable and effective.

Arrangement of the box

Installing a chimney on a gas boiler may be accompanied by the installation of an external casing around the pipe itself. Such a box is required when arranging a ceramic channel. Other types of pipes are protected by a box with a heat-insulating layer in those areas where the chimney passes through unheated rooms, the attic.

The heat insulator should be basalt wool, which can withstand heating up to at least +300 ° C. Due to the insulation of the pipe, the main part of the exhaust gases does not have time to cool and condense.

Chimneys for units with a closed combustion chamber

A heating unit with a closed combustion chamber is a gas boiler with a chimney and an air intake pipe through which air from the street enters the burner. The coaxial chimney is delivered ready-made and quickly assembled on site. Its diameter must match the diameter of the outlet pipe of the boiler.

coaxial chimney

In the course of work, the pipe is connected to the gas boiler nozzle and removed horizontally through the wall at a convenient height (turn 90 degrees). A number of rules must be followed:

• between the ceiling and the horizontal section of the chimney, the gap must be at least 20 cm;
• the outer edge of the pipe must be removed from the surface of the outer wall by at least 30 cm;
• the distance between the chimney and the ground surface must be at least 20 cm;
• from the edge of the chimney to the wall of the neighboring building should be at least 60 cm.

Coaxial chimney installation diagram

In regions with a harsh climate, when choosing a gas boiler with a closed combustion chamber, you should pay attention not only to the amount of kW of power, but also to the presence of protection of the coaxial chimney from freezing. Cold air in the outer contour of the pipe can supercool the condensate and it will freeze on the inner walls, clogging the channel.

Without a competent approach to the arrangement of the chimney, the normal functioning of the heating equipment is impossible.

If gas is chosen for heating in the house, care should be taken to remove combustion products. This means that you need to choose and correctly install a chimney for a gas boiler. Compliance with the rules and regulations in this matter cannot be categorically neglected, since this can call into question not only the health, but also the life of the residents of the house.

One of the most dangerous products formed during almost all types of combustion is carbon monoxide. This is an insidious and very dangerous substance, the inhalation of which threatens with severe forms of poisoning.

During the operation of a gas boiler during the combustion of fuel, carbon monoxide is also formed in addition to other combustion products.

If the chimney that removes the products of combustion is not installed correctly or is damaged, this can lead to poisoning.

The danger should not be underestimated. Carbon monoxide (aka carbon monoxide) is odorless and colorless, so poisoning can occur completely unnoticed by everyone in the house.

Once in the human body, carbon monoxide molecules interact with hemoglobin. As a result, the so-called carboxyhemoglobin is formed, which prevents the entry of oxygen molecules into the tissues of the human body.

In addition, carbon monoxide can have a very bad effect on other biochemical processes in the body. There were cases when carbon monoxide poisoning was detected too late, the person simply could not be saved.

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Gas equipment remains the most economical and unpretentious type of heating equipment. The only difficulty, judging by the reviews, is the high requirements for the installation of both the heating unit itself and the smoke exhaust system.

The chimney of a gas boiler in a private house is carried out in accordance with SNiP and PPB. Any violations lead to a refusal to put the equipment into operation by gas service employees.

Despite the high standards, making a chimney for a gas boiler with an open combustion chamber with your own hands is much easier than it might seem the first time. To complete the work you will need:

1. Select the type and design of the chimney.
2. During installation, take into account existing rules and requirements.
3. Prevent and avoid common mistakes made during installation.

Subject to all of the above, you can install a smoke exhaust system for an atmospheric boiler yourself.

What is better to make a chimney for a gas boiler

The high requirements for a chimney for a gas boiler in a private house are a good reason why it is necessary to choose a suitable flue system with particular care. Not all types of chimney are suitable for this purpose.

Consider the most common options for smoke exhaust systems:

• Galvanized flue pipes are the cheapest way to make a chimney. The low flue gas temperature makes it possible to use galvanization for connection to a gas boiler. The pipe has several disadvantages: it burns out quickly, needs careful insulation, etc.
  Additional information regarding the possibility of operating a galvanized chimney can be found in.

  

• Ceramic fume extraction systems - ceramics have one of the best ratios in terms of reliability, service life and thermal performance. For a gas boiler with an open combustion chamber, a chimney is needed that can provide stable draft, no condensate. The disadvantages of ceramics are the large weight and high cost of construction.
  Once installed, a ceramic chimney will last at least 50 years. Read more about technical specifications and installation rules.

  

• Stainless steel sandwich pipes are one of the most successful smoke exhaust systems for connecting to a gas boiler. The pipe consists of two contours, between which a non-combustible layer is laid. Design features ensure the almost complete absence of condensate and the accumulation of soot.
  Popularity adds a simple installation of a sandwich pipe and the ability to connect yourself. How to choose and install a stainless sandwich pipe is described.

  

• Enamelled pipes - this type of pipe is coated with a protective layer that prevents wall corrosion and improves the appearance of the structure. The enamel withstands heating up to 550°C, therefore, the standards allow its operation as a chimney for an atmospheric gas boiler.

  

• Brick flue - is used exclusively after the internal channel has been lined. The service life of brickwork, without loss of tightness, is only 7-8 years. After, the pipe loses its tightness. Installing a metal stainless pipe inside the brick channel largely solves the problem of insufficient traction and loss of sealing.
  Brick chimneys for gas boilers have been practically not used recently. Find out a detailed guide on choosing masonry material and installation work.

  

A chimney for a gas atmospheric boiler in a private house is best made of ceramic or stainless sandwich pipes. During installation, the design features and material of the smoke exhaust system are taken into account.

For the chimney, it is better to use a stainless pipe, marked AISI 416 and at least 0.8 mm thick. Such steel resists acid attack well and is resistant to burnout.

Rules for the construction of chimneys for atmospheric gas boilers

Building codes and regulations (SNiP) are presented to the gas chimney pipe, which separately indicate:

• Ventilation and heating of residential premises, using gas equipment -.
• Recommendations and requirements for gas distribution systems and removal of combustion products from the premises -,.

Using the legal regulations, it is enough to simply ensure that the smoke exhaust system complies with the PPB, calculate the height and diameter of the chimney, and also determine the frequency of its maintenance.

Fire safety requirements for the chimney

As already noted, there are detailed rules for the safe use of gas appliances with an organized removal of combustion products into the chimneys. Some points are separately stipulated in the PPB. Individual norms change from time to time, but in general, the main instructions remain unchanged.

Fire safety requirements for chimneys from household gas heating appliances may vary, depending on the region and emerging situations. Before connecting the smoke exhaust system, it is better to ask the representatives of the Gas Service about the existing standards.

How to calculate the height of the boiler chimney

In order to properly make a chimney for a boiler with an open combustion chamber with your own hands, not only fire safety rules are taken into account, but calculations are also made in accordance with existing SNiP.

The main task of the smoke exhaust system is the safe removal of combustion products from a residential building. This will require stable and steady traction. In this regard, building codes have been developed that stipulate what the height of the chimney should be.

Calculations can be made independently, using the following recommendations:

• The height of the chimney for a gas boiler in a private house is calculated depending on the distance of the pipe from the ridge of the building. If the distance between the center of the roof and the head of the pipe is not more than 1.5 m, it must be raised by at least 0.5 m. At a distance of 1.5-3 m, it is allowed that the pipe be flush with the ridge. If the chimney is more than 3 m away from the ridge, the head can be lowered 10° below the ridge.
• The length of the chimney, in order to provide the necessary draft, must be at least 5-7 m.

Modern gas boilers have a built-in sensor that detects the presence and strength of draft in the pipe. If the automation constantly gives a shutdown signal, then the calculations were performed incorrectly - you will need to increase the length of the chimney.

How to choose the diameter of the chimney

There are strict requirements of the gas service for the diameter of the chimney and ventilation, which include several important aspects:

• The chimney diameter must be as specified in the technical documentation of the boiler.
• It is not allowed to reduce the diameter of the channel. The minimum cross section of the chimney pipe is the same as that of the boiler outlet. It turns out that if the outlet channel on the boiler is 150 mm, then the channel must be at least 150 mm.
• If necessary, you can increase the diameter of the pipe.
• In the room used for the boiler room, at least there should be natural ventilation.

The main requirement for the diameter of the chimney remains strict adherence to the recommendations of the manufacturer of the boiler unit.

Is it necessary and how to insulate the chimney pipe

The reason for the formation of condensate in the chimney shaft is poor pipe insulation. There is such a thing as "dew temperature". The purpose of the insulation is to ensure that during the operation of the smoke exhaust system, heating above this parameter is carried out as quickly as possible.

Methods for properly insulating the chimney depend on the chosen chimney. Thermal insulation can be done in the following ways:

• Basalt wool - the material is simply wound onto the pipe, fixing it with clamps or knitting wire.
• Heat-insulating shells - optimally suited for chimney insulation. Basalt shells have the necessary parameters for use in flue systems with low flue gas temperatures.
• Basalt mats and cardboard - used to insulate a brick chimney. Mats are used for subsequent plastering.

How to check and increase the draft in the chimney

Several parameters affect the traction characteristics of the chimney:

1. Pipe diameter.
2. Chimney height.
3. Section.

If, after installing the chimney, there are signs of poor draft: an increase in the volume of condensate that falls out, a stop of operating equipment, it will be necessary to increase the circulation of combustion products in the pipe. You can do this in the following ways:

• Install the deflector on the chimney. Practice has shown that the installation of a draft limiter improves the speed and intensity of the removal of combustion products by 1.5 - 2 times.
• Perform pipe maintenance. A decrease in draft often occurs after 2-3 years of operation of the chimney without its maintenance. After cleaning the pipe, the characteristics are restored in full.
• Increase the length of the chimney. If the pipe height parameters are not observed, the traction force will be insufficient. The problem can be solved by lengthening the head.
• Another option is to initially install a forced draft chimney. Not every pipe is absolutely suitable for forced draft gas equipment, therefore, before purchasing, you should carefully study the technical documentation of the boiler.

Do I need to ventilate a room with an atmospheric boiler?

Boiler rooms with installed household floor and wall gas boilers with an open combustion chamber are equipped with natural ventilation. This is due to the fact that during operation the boiler burns the air taken from the room.

Representatives of the gas service are scrupulous about the total area of ​​\u200b\u200bthe boiler room, ceiling height and other parameters that affect the flow of fresh air. So, the lower part of the door should not be adjacent to the door frame, forming a gap for the free flow of air into the room. The boiler room itself must have a ventilation duct, as well as windows for ventilation.

How often should you clean your chimney

The legislation provides a period of time during which a periodic inspection of pipes should be carried out. As a rule, maintenance of smoke exhaust systems is carried out at least 1 time per heating season.

To facilitate subsequent maintenance, a condensate collector and an inspection hatch are installed in the pipe to drain condensate and clean soot. The correct arrangement of the chimney when installing a domestic gas boiler includes the arrangement of the nodes necessary for servicing the system, with free access to them.

The main mistakes when choosing a flue for a gas boiler

The most common mistakes when installing a chimney are:

1. Incorrectly selected height and diameter of the pipe.
2. Lack of thermal insulation when installing an attached external chimney or when passing through an unheated attic.
3. Non-compliance with the rules of the PPB.

Self-installation of the chimney of a gas atmospheric heating boiler in a private house can save approximately 20-30% of the total cost of the chimney system, but has certain disadvantages.

It is almost impossible to avoid violation of SNiP and technical requirements when constructing a gas duct without special knowledge and training. Any violations will lead to a refusal to commission the boiler, column and other heating equipment. Additional improvements and alterations will be required, which will not be reflected in the budget.

Installing individual gas heating of a wooden country house should be entrusted to professionals. Only in this case can the safety and long service life of the flue be guaranteed.

Installing a chimney for a gas boiler is not such a difficult and impossible task for a home craftsman. It is quite possible to do it yourself. The main thing is to carry out all operations without violating generally accepted building codes and always remember fire safety standards.

Many novice craftsmen are sure that the flue gas duct is best assembled from bricks. Let's disappoint them. Nowadays, such chimneys for gas units are no longer made. There are many reasons for this, we will highlight only the main ones. Firstly, modern heating equipment is characterized by increased efficiency of gas combustion. In the area where the outlet pipe is connected to the boiler, the flue gases are heated up to approx. 100°C.

When they rush up the hood, their sharp cooling is observed. As a result, the transformation of gases into condensate is observed. It immediately settles inside the chimney, clogging it. This leads to a decrease in the functionality of the outlet line. Secondly, the labor costs for laying brick exhaust systems are objectively high. You will spend a lot of time building a chimney. And get an outdated design in all respects.

Masonry brick exhaust system

The indicated disadvantages of brick gas outlet lines are also inherent in structures made of asbestos-cement, as well as galvanized metal pipes. Theoretically, chimneys are allowed to be made from such products. But their quality will not be at the highest level. If you decide to build a truly functional and efficient chimney with your own hands, experts recommend choosing the following types of outlet tracts:

1. coaxial design. Such structures for gas boilers are characterized by attractive appearance and excellent working potential. Coaxial type hoods are good because condensate collects in small volumes on their surface (internal). This fact is very important for any heating units. And first of all for gas boilers of interest to us.
2. Exhaust gas path made of ceramics. This design is probably the easiest to build with your own hands. It has such advantages - a high level of fire safety, ease of installation, affordable cost of all necessary elements and materials. Ceramic structures are built by home craftsmen who do not like to throw money away. The construction costs of such chimneys are always low.
3. Highways from corrosion-proof pipes. These are currently the most popular hoods for private houses where gas boilers are installed. They are highly resistant to the aggressive effects of exhausted combustion products and to mechanical stress. Stainless steel products are also very durable. Such chimneys are sandwich systems. They consist of two pipes of different sections. One of the tubular products (with a smaller diameter) is placed in a large pipe. At the same time, the space between them is filled with a heat-resistant layer - basalt wool.

According to the pros, stainless sandwich structures are the ideal option for an exhaust line for a gas boiler. However, you can build a chimney from other components. All in your hands.

Chimneys for gas heating units can be mounted outside (attached structure) and inside the house. Easier is the do-it-yourself installation of the first type of chimney. To equip it, you need to bring a pipe of a certain section to the street through a hole in the wall of a residential building.

Installation of an attached chimney for a wall-mounted gas-fired boiler is carried out as follows:

1. Cut a hole in the wall surface. Insert a piece of stainless pipe (or products made of other material) into it to a depth of 5–25 cm.
2. Assemble the vertical section of the mounted line using a suitable swivel elbow.
3. Seal the joints with refractory compound. It is also recommended to further strengthen these areas with clamps equipped with a threaded tie.
4. Wall brackets (they are sold in all building stores) fix the pipe every 100–200 cm.
5. Apply an anti-corrosion coating to the chimney (if we are talking about steel products).

Do-it-yourself installation of the structure is completed by the procedure for its insulation or any other non-combustible material. Important advice! Attached hoods are desirable to be assembled from two-layer tubular products, which are considered as safe as possible in operation. In addition, they are easily thermally insulated and guarantee a high-quality inflow of air flow into the furnace of a gas unit.

Insulation of the chimney of a gas boiler with mineral wool

Installation of internal chimneys, as a rule, is carried out at the stage of construction of a residential building.

Such hoods are mounted in compliance with (strict) fire safety rules. The slightest oversight - and during operation the chimney can catch fire. In this case, it is important to carefully protect the areas where the elements of the smoke path pass through the roof structure and the ceilings between the floors of the house. An internal chimney can also be installed in an already operated building. The algorithm for doing such work with your own hands is presented below:

1. Cut holes in the roof and ceiling surface for mounting the hood.
2. Install special pipes in the “holes” made (they are called through pipes). Outwardly, they look like a cube in which special holes are made. The cross section of the pipes is selected so that the main pipe enters them as tightly as possible.
3. Proceed to the assembly of the chimney. The operation is performed from the head of the heating boiler - from the bottom up. The structure should be rigidly attached to the wall every 200–400 cm using brackets.
4. In the place where the outlet line is laid through the roof, it is necessary to lay a sheet of metal, and then protect this area with non-combustible thermal insulation. Experts recommend treating the joint with a good heat-resistant sealant to minimize the risk of fire.

Note! External exhaust hoods are insulated along the entire length of the line, and internal ones should be thermally insulated exclusively on their upper part. Another small nuance. Internal chimneys are suitable for both floor and for. But the attached structures are recommended only for wall-mounted units.

If you plan to do all the operations for arranging smoke exhaust facilities with your own hands, remember the following rules:

1. The chimney is assembled with a minimum length of horizontal sections. It should be predominantly vertical. The presence of horizontal segments with a total length of up to 5 m is allowed. At the same time, the use of more than 3 bends for the construction of the highway is strictly prohibited.
2. Surfaces that are located next to the installed gas exhaust tract must be treated without fail with refractory compounds and heat-resistant materials.
3. When calculating the cross sections of holes punched in the roof and interfloor ceilings, consider the thickness of the thermal insulation layer, and not just the cross section of the pipe being installed.
4. The height of the exhaust pipe varies from 50 to 500 cm. Its specific value depends on how it is located in relation to the roof ridge.
5. The inner surface of the hood must be smooth and have a constant cross section along the entire length of the line.
6. All subroofing and interfloor connections are made completely tight. Important - the organization of joints inside the ceilings between the individual parts of the chimney is unacceptable!

Small windows should be installed on the knees of the exhaust structure and on its horizontal sections, which will allow you to regularly clean the structure. It is also recommended to put a dropper a little below the heating boiler nozzle - a special reservoir. It is necessary to collect condensate.

Installing a dripper on a chimney

If there are 2-3 gas units in your house, they can be connected under one exhaust system. But there are two conditions for the implementation of such a scheme:

1. The cross-sectional area of ​​the outlet line must be equal to the area of ​​the widest branch pipe (outlet) of the gas installations used.
2. In height, the distance between the flue gas entry points from different boilers should be 0.75 m.

Mount a high-quality chimney with your own hands, guided by the tips outlined in the article. And then you will not have any problems with the operation of the heating system!

The chimney pipe, which rises above the roof, is only a small visible structural element of the complex mechanism responsible for the removal of smoke and gas. Regardless of what fuel the heating equipment runs on (solid, liquid or gaseous), it must be supplemented by a system for removing combustion products. Each homeowner should have an idea about the structure of the chimney in his house, which will allow him to properly operate the heating system in principle. For those who only have to solve similar problems of arranging their home, before going to a specialized store or inviting professionals, we suggest that you first familiarize yourself with the theory. Let's take gas heating as an example. To begin with, at a minimum, you need to know what chimneys for gas boilers are, what are their strengths and weaknesses.

Types of chimneys: what will the specialist offer?

Can you make your own chimney? Of course! Although, if this work has to be done for the first time, then the consultation of a specialist will by no means be superfluous. But, one way or another, you still have to figure out what kind of chimneys for boilers exist at the moment.

So, you may be asked to choose one of the following options:

Option # 1 - classic brick

Although its construction will be offered to you, it is unlikely, since it is not even yesterday, but the day before yesterday. A brick chimney is characterized by a complex design, high cost and its construction takes a lot of time. In addition, in many operational characteristics, such a chimney is inferior to more modern designs.

Option #2 - Stainless Pipe

Here the manufacturer offers a wide range of models. Among the advantages, it is impossible not to note the high resistance to mechanical damage and the effects of an aggressive environment. A chimney for a gas boiler made of stainless steel, as a rule, is made in the form of a sandwich system - two pipes of different diameters one inside the other. The empty space between them is filled with heat-resistant basalt wool.

The stainless steel chimney is reliable and has a presentable appearance

Without exaggeration, to date, a chimney for a gas boiler using a stainless "sandwich" is one of the most successful solutions to date.

Option #3 - coaxial chimney

You can’t confuse it with another design, a distinctive feature is a presentable appearance. Although the operating parameters are at a high level. Moreover, the coaxial chimney for a gas boiler has a specific shape, on the inner walls of which condensation does not form. This moment is very important especially for gas-fired heating systems.

Option #4 - ceramic design

It cannot be said that it enjoys great attention from the consumer audience in the elite construction segment. And, where preference is given to simplicity and reliability, ease of installation and fire safety, and at the same time an affordable price, a ceramic chimney has no alternative.

Whatever technology is preferred, in the end, a chimney for a gas boiler involves working with such elements:

• Adapter connecting the heating boiler pipe and the chimney.
• Pass pipe.
• telescopic pipes.
• The bracket and clamp are the main wall mounts.
• A tee with a revision - in the lower part there is a special fitting for removing condensate.
• The tip is conical.
• Branches.

We invite you to watch an overview video with tips from a specialist:

What affects the efficiency of the chimney?

Perhaps the question is posed somewhat incorrectly from the point of view of a professional. Since the health, and sometimes the life of people, depends on the efficient operation of the combustion products removal system, it is more expedient to consider the requirements for the chimney of a gas boiler.

A chimney of any design must be made in accordance with the requirements of SNiP 2.04.05-91, as well as DBN V.2.5-20-2001. Otherwise, there will be an incorrect chimney device and heating equipment connected to it. And this, in turn, calls into question the safety of operation of the entire heating system. These documents clearly regulate the arrangement of boiler chimneys. These documents are subject to careful study, since violation of the norms set forth in them will necessarily lead to problems with the gas economy.

If you briefly state the requirements for chimneys of gas boilers, then first of all you need to pay attention to such points:

• Good traction is the key to efficient use of thermal energy from gas combustion.
• Proper design of the condensate trap - excess moisture should not accumulate on the walls of the chimney channel.
• It is forbidden to install deflectors, fungi, etc. on the chimney head. These elements reduce the efficiency of removing combustion products, and there is a risk of carbon monoxide entering the room.
• Requirements for chimneys of gas boilers require maximum attention to the installation work. Particular emphasis should be placed on the tight fit of structural parts at the joints, that is, maximum tightness should be achieved. This will prevent hot gases from penetrating outside the chimney.
• The use of common connecting flue pipes for several units is allowed.

Outwardly, it seems that the chimney is brick. In fact, it's just a finish, and it is inside the pipe

Algorithm for installing a chimney inside a building

Installation of a chimney for a gas boiler can be done both inside the building and autonomously (outside). You can understand what the difference is, while drawing certain conclusions regarding your particular case, from our small table.

As they say, draw your own conclusions.

We bring to your attention the internal structure of the chimney system. Briefly, this process consists of the following steps:

1. Drawing markings in ceilings and roofing cake for chimney holes. We check the correctness several times.
2. Cut out the opening for the pipe.
3. The branch pipe departing from the boiler is connected to the transition adapter.
4. A tee and a revision are connected, a steel sheet is attached, and the main bracket is installed.
5. The pipe is built up, if necessary, “knees” are used.
6. For installation through ceilings, a special pipe is used.
7. A sheet of galvanized steel is put on the pipe, in which a hole of a larger diameter is previously made than the chimney pipe. Galvanization is fixed to the ceiling.
8. To strengthen the joints, clamps are used, which are tightened with bolts or high-quality wire.
9. The chimney itself is attached with wall clamps, step - 2 m, as well as brackets, step - 4 m.
10. A special cone-shaped tip is designed to complete the design.
11. The chimney is insulated.