Chimney for the furnace: design features and basic installation rules. Metal chimneys for stoves - selection and installation rules Chimneys for stoves

Our ancestors, living on the territory of almost the most cold country on the planet, in winter they heated their dwellings with wood-burning stoves. In an era when every residential building is equipped with gas cat, stoves and fireplaces have become exotic, the installation of which serves as an element of decor, and not a practical necessity. However, these devices are still heating, therefore, they require the organization of smoke removal. In this article we will tell you how a chimney for a fireplace is made.

Chimneys for fireplaces or stoves - channels through which the mixture of gases, which is the products of combustion of fuel, is removed from the furnace heater in atmosphere. The design of these elements heating system is carried out in the form of a pipe or a brick shaft, the tightness of which determines whether the system works correctly. Chimneys for fireplaces and stoves are necessary, since without them it is impossible to operate heat-generating devices, the operation of which is as follows:

1. Fuel is placed in the furnace of heat-generating equipment (stove, fireplace, boiler). Basically, the devices operate on wood, gas, compressed or coal, fuel oil.
2. Fuel is ignited using a source open fire, resulting in the system producing a large number of heat used to maintain optimum temperature indoors, and smoke.
3. Smoke, which is a product of fuel combustion, consists of a mixture of carbon dioxide and carbon monoxide, ash, soot, and other aggressive chemicals. The temperature of the smoke entering the chimneys for fireplaces or stoves reaches 400-500 degrees, therefore, obeying the law of convection, it rises, making room in the furnace for cooler air.
4. The design of the smoke exhaust ducts is a vertical sealed shaft through which hot smoke rises only upwards. Thanks to this process, Fresh air, saturated with oxygen, necessary to maintain combustion.

The process of sucking oxygen-rich air into the furnace is called draft. To check the chimneys for fireplaces for draft, you need to bring a lit match or candle to the firebox: if the flame deviates towards the smoke exhaust duct, then the system is working correctly. If the candle flame burns evenly, they say that there is no thrust. But the most dangerous situation develops when a reverse thrust is formed, it is signaled by a flame that has deviated in the opposite direction from the chimney.

To properly make a smoke exhaust channel for a stove or fireplace, you need to carefully study the information about the heater specified in the instructions, as well as calculate the volume of gas in the furnace. Mounting a chimney for a fireplace with your own hands is quite difficult, since this complex structure requires special knowledge and experience that only experienced craftsmen can boast of.

Placement methods

Assembly and connection of the smoke exhaust channel occurs after the installation of the heater. However, it is necessary to choose a place and calculate the section and pipe before installation. Chimneys for fireplaces or stoves are placed in two ways:

Note! The calculation of the smoke exhaust channel of the heater determines the recommended section and height of the pipe, calculates required level thrust to sustain combustion. When calculating these parameters, the power of the device, the type of fuel used, the location and climatic conditions in the region of construction. Chimneys for fireplaces are built on the basis of a project that takes into account all of the above factors, and the connection is made under the supervision of a professional craftsman.

materials

Chimneys for fireplaces are made from various materials, which have high thermal stability, low thermal conductivity, excellent refractory properties, do not enter into oxidative reactions with water, and also do not interact with aggressive chemicals contained in the products of combustion. To make a durable and reliable smoke exhaust channel for the stove, use the following materials:

Important! The material for assembling the chimney is chosen based on the type of fuel on which the heat generating device operates: for fireplaces and stoves running on solid fuels, brick and ceramic pipes are better suited, with smoke exhaust from gas models steel sandwich pipes do a good job.

Requirements for smoke exhaust ducts

The use of heating vents is associated with the risk of fires and poisoning. carbon monoxide, therefore, strict requirements are imposed on smoke exhaust channels, the task of which is to protect users. In order for the operation of the equipment not to cause problems, the following conditions must be met when installing the chimney:

Important! Experienced furnace masters when discussing a fireplace project, it is advised to insist on placing the chimney inside the house, and be sure to have it on the inside, not the outside wall. With this installation scheme, the channel turns out to be warmer, there is no draft deficit and vapor condensation in it.

Video instruction

The function of chimneys for wood stoves is to remove smoke and other combustion products from the room. And in order to given element heating system successfully coped with the task, when arranging it, it is necessary to observe a number of essential requirements. What are the rules for building a smoke outlet for a wood-burning stove will be discussed in our today's article. But first we will talk about the classification of wood stoves.

Classification of wood stoves

Wood burning stoves differ from each other in such parameters as:

• material;
• principle of operation;
• design features.

Wood burning stoves in terms of material

Most often, wood stoves are made of cast iron, steel or brick. The surface of these heaters is smooth and quite attractive in appearance, so they fit well into the interior of any room.

The furnace, made of metal, is equipped with a special refractory glass door, which allows you to control the combustion process and add fuel in time.

Cast iron stoves are a kind of rarity, now they are very rare, mainly in villages. Such devices are beautiful, they exude antiquity and some kind of rural romance.

Brick ovens are a "classic of the genre." It is they who are built in our country most often in the form of high, almost to the ceiling, structures lined with tiles. Such heating devices heat up for a long time, but they also cool down for a long time, keeping the temperature in the room comfortable for living for a long time. Therefore, it is worth knowing what are its features.

Advice! In order to achieve maximum heat transfer from a wood stove, it is better to install it near the inner wall of the room.

Types of stoves according to the principle of operation

• traditional devices operating up to 5 hours;
• ovens long burning, structurally more complex and capable of heating the room for a long period of time. This is made possible by controlling the intensity of combustion by adjusting the air supply.

Types of furnaces depending on design features

If you look at wood stoves in terms of their design, the classification will be as follows:

• heating;
• heating and cooking;
• fireplaces;
• ovens with a water circuit.

As can be understood from the name, heating furnaces firewood is used exclusively for heating the air in the room. The second variety, that is, heating and cooking stoves, allow you to heat the room and cook. Fireplaces are not just a heating device, they are a real decoration of the interior, a kind of “highlight”, central element room, which is so nice to gather with the whole family and share the news.

Devices with a water circuit are used for space heating and hot water. Such devices are especially popular in places where there is no centralized hot water supply.

It is better to place the chimney closer to the ridge. If this is not possible, you can mount it in an external wall, additionally protecting it with a layer of thermal insulation to prevent freezing during the cold season.

When choosing a material for the manufacture of a pipe, its properties such as fire resistance, resistance to corrosion and aggressive media should be at the forefront. It is also necessary to correctly select the shape of the chimney, since the traction force depends on it. Optimal solution- a chimney with a circular cross section, because if the cross section is square, the draft decreases, moreover, soot will accumulate in the corners. Take care about .

Advice! To improve draft, make a chimney for a wood-burning stove with a round section.

To ensure easy timely maintenance of the chimney, it is advised to make its inner surface smooth. Soot accumulates less on it, which prevents the release of combustion products and can even lead to a fire.

Those parts of the smoke duct that are in contact with the floor elements must be finished with metal plates to increase the level of fire safety. If wooden buildings are located near the outer part of the chimney, a spark arrester is indispensable.

What not to do when arranging a chimney for a wood stove

It is not necessary to equip several furnaces with a common chimney. Each heater must have its own pipe.

Advice! A common chimney for several heaters is only allowed if they are on the same floor. However, it is necessary to provide for two cuts and valves.

Smoke must not be expelled into ventilation ducts.

Arrangement together with a chimney is unacceptable.

findings

As you can see, there is nothing complicated in building a chimney for wood stove no. The main thing is to follow the rules listed above, and the heater will serve you for decades!

Related videos

Although manufacturers today offer private housing owners a wide variety of heating boilers, however, many of them prefer to install stoves or fireplaces in the house, because thanks to them, space heating requires minimum costs. Any heating equipment needs reliable removal of combustion products. That is why during its construction it is necessary to pay special attention to both aesthetic characteristics and operational characteristics.

The required level of traction that provides the most comfortable and safe conditions to stay in a particular room creates a chimney for the stove. It is an air channel through which the products of combustion come out. It can be an ordinary brick pipe or modular metal types, it is only important that it functions properly.

Basic structures

Outlet channels through which the utilization of air saturated with combustion products passes are necessary not only for stoves, but also for fireplaces or heating boilers or gas water heaters.

We list the main types of chimneys for furnaces.

• Direct current. This is one of the first systems through which combustion products were removed. They have a significant drawback - due to the non-stop removal of gases to the outside, the main part of the generated heat is also carried away.
• Direct-current structures equipped with transverse jumpers. These small additions allow some of the heat to be retained. When heated, the jumpers transfer heat to the walls of the heating unit. The same design is typical for a stove without a chimney in baths: the stones in them are heated by hot combustion products.

• With labyrinth. There are many varieties of such structures, but they all have one thing in common. common features. In particular, this applies to the rate of removal of gases. It is quite low, since the exhaust gases are passed through a tortuous channel. In the process, the device itself warms up in parallel and ensures maximum heat transfer.

• Became a classic, Russian stove. The scheme of the chimney is bell-shaped. The incandescent gas rises up, cools down a little on the sloping arch of the hearth and descends to the channel. The disadvantage of such a system is that it warms up unevenly. For example, in the lower part of the hearth, it does not warm up at all, since the heat mainly goes to the roof.
• Modular. Unlike the classic brick version smoke removal, they are made of metal. They are used in gas heating systems. The fact is that the products of methane combustion are acidic compounds that destroy bricks with their aggressive effect.

Device Features

The efficiency of brick, metal, flexible chimneys for stoves and others depends on several factors, for example, material and dimensions, section, height.

• It is preferable that the chimney pipes, say, for a bath, represent a regular circle in cross section, that is, they have cylindrical shape. Outgoing smoke with this configuration, in contrast to the angular one, does not encounter obstacles in its path and is discharged with the least resistance. In addition, a minimum of soot accumulates on the walls of the outlet pipe.
• The outlet of the heating device must match in cross section with the chimney channel. If the width of the latter in the connection area turns out to be greater, which occurs quite often, then a special reducing adapter is installed, which must be carefully sealed at the junction. The extensions of the pipes during docking should be directed upwards in order to prevent condensate and resins from flowing along their outer wall.

• The horizontal part of the channel design requires special attention. Warm smoke, as you know, moves vertically upwards, therefore, in these areas, moisture is especially actively condensed and deposited. thick layer soot. To compensate for such undesirable consequences and improve traction, it is necessary, firstly, to strictly limit the length of these segments: they must be less than 1 m in length, and, secondly, to provide condensate collectors and inspection doors there.

The right chimney for sauna stoves- exclusively vertical. However, it is permissible to lay the pipe at a slight slope, provided that the length slope no more than 2 m.

Main stages of calculation

The calculation of the chimney is carried out taking into account such parameters as the power of the connected heating device, shape and others. Optimal Height and the cross-sectional diameter is calculated based on the SNiP of the furnace and chimneys.

Height above roof

To determine the height of the outlet channel of boilers industrial production use a special formula that describes its relationship with the static draft, the average temperature (K) in the pipe and the average value of the outside air temperature in summer period. If necessary, the value obtained from the calculation results is adjusted upwards, taking into account the following rule:

When calculating the height, the height of neighboring buildings is also taken into account: in the case of higher ones, the channel is taken out above their roofs.

Pipe area

In practice, they usually do without special calculations, based, depending on the power of the unit, on the following cross-sectional values:

• less than 3500 W - 14 × 14 cm;
• 3500–5200 W - 14 × 20 cm;
• 5200–7200 W - 14×27 cm.

The cross-sectional area of ​​the cylindrical channel is assumed to be the same.

If the cross section is significantly larger than the calculated value, then the thrust will deteriorate, and as a result, the system will work unstably. A smaller cross section leads to poor removal of combustion products up to the complete cessation of this process.

Material

The choice of material for the construction of the flue system is based on the type of fuel used for heating. For example, for gas equipment MDS ceramic pipes are best suited, while brick pipes can quickly collapse.

The classic version of the device for the exhaust system is considered to be a brick chimney for metal furnace. brick construction assembled exactly according to the project, where the laying of each layer of the channel is prescribed separately. In this case, it is necessary to obtain a minimally rough surface from the inside and ensure complete tightness.

Today, stainless steel is most often used. In construction steel pipes can be: isolated and non-isolated:

• uninsulated are used exclusively for internal installation furnaces and chimneys: they are installed in a special shaft;
• when installing a pipe outside it in without fail insulated to prevent moisture condensation inside the pipe.

Security

For safety reasons, the chimney must be properly insulated, especially if the duct passes through ceilings in the immediate vicinity of combustible materials. are based on the type of floor material and on the temperature of the pipe. It is great if the walls and ceiling near the place where the structure passes are finished with fireproof material. If this is not the case, then the heated parts are isolated from hazardous materials using metal sheets and a layer of non-combustible materials.

The part of the pipe that goes out must be securely fixed and protected from the wind. From above they are covered with deflectors to protect them from precipitation. gas boilers in this matter are an exception: the protective cap on the chimney pipe in this case is a violation.

Some information from SNiP used when installing the chimney of the stove and fireplace

• Smoke exhaust ducts can also be located on outer walls in the event that they are made of non-combustible material, and heating device located near the interior. At the same time, external thermal insulation is required, which will not allow condensation of moisture inside the pipe.
• Brick channels complement the pockets needed for cleaning. They are closed with a brick (laid on the edge) or a door is installed.
• For roofs made of combustible materials, it is necessary to provide a mesh spark arrester, which is installed along the upper part of the channel. If the latter is made of brick, then between it and combustible materials it is necessary to provide a gap of 13 cm, in the case of non-insulated ceramic - 25 cm, and for insulated - 13 cm.

• Installation of stoves and fireplaces gas fuel has its own characteristics. The connection is made using flexible metal pipes included in the equipment kit. A prerequisite is the presence of a vertical section in the system, and the distance between the axis of the horizontal and the line of the lower level of the nozzle must be at least 50 cm. This distance can be reduced, for example, if the ceiling height is less than 270 cm
• twice if the heating unit is equipped with a draft stabilizer;
• up to 15 cm if there is no stabilizer.

• In a new building maximum length of all horizontal sections is more than 3 m, in the old building - up to 6 m. The pipe is installed with a slight slope in the direction heating unit. If two units work in the house, then they can be connected to a common outlet channel. They should be separated from each other at a distance of less than 75 cm.
• The outlet channel can have a maximum of three turns, the radius of curvature of which must exactly match the diameter of the pipe section.

The technology of laying a brick chimney in itself is quite simple and understandable, since, unlike the brick oven itself, the pipe usually does not have internal channels that are complex in configuration. However, despite the relative simplicity of the design, one cannot but take into account the enormous importance of this department of the furnace, since the quality of the heating of the house and the safety of both the building itself and the people living in it directly depend on it. Therefore, in order for all the work to be crowned with success, it is necessary to approach it with the utmost care, based on the recommendations experienced craftsmen and on developed and tested design schemes.

When erecting a chimney, it should be remembered that the evenness of the inner walls of the channel is no less important than aesthetics. outdoor masonry. Not only the stability of the required draft in the furnace depends on this circumstance, but also the duration of operation of the chimney without cleaning, since the smoke rising through the pipe leaves on smooth walls, without protruding mortar and deep seams, a much smaller amount of fuel combustion waste, and the channel overgrows much slower.

What are brick chimneys?

Chimneys of brick ovens can have different types, depending on the place of their installation, the design of the furnace, and also on how many heaters will be connected to the pipe. So, there are three main types of chimney brick pipes: these are mounted, root and wall.

• Wall-mounted chimneys . The most widely used constructions are packed pipes. They are good because they are compact and do not occupy at all additional space indoors, but are simply a vertical extension of the oven.

They are erected on top of the last row of bricks covering the furnace, around the left hole. The pipe is then passed through attic floor, attic, truss system and rise above the roof.

• Indigenous chimneys . This type of pipe is installed in cases where it is planned to connect a metal stove to it, or several heating appliances located on one or even several floors.

In addition to metal, such a pipe can be connected and brick ovens. This type of chimney is especially convenient if it is necessary to build two stoves in the house in neighboring rooms. For example, a kitchen needs an oven with hob, and for the next room - only heating. In order not to lay out a separate pipe for each of them, a root chimney is built between the rooms, to which both heaters are connected. Not only two, but also three or four stoves located on different floors of the house can be connected to a pipe of this type. In any case, it is necessary to calculate the size of the internal chimney channel very accurately, otherwise normal draft may not be ensured when several devices are operating simultaneously. The answer to the question why may be different.

• Wall chimneys line up near the main (external or internal) walls or are built into them. They can be used, just like the main ones, to connect several furnaces located on different floors of the building.

The convenience of this design lies in the fact that it is, as it were, outside the living quarters, without occupying their area. For example, on the first floor of the house a fireplace can be built and connected to the wall chimney (there the pipe will be more similar to a wall-mounted one according to the principle of structure), and on the second floor a smoke outlet of a metal stove is embedded (as in the version with a root requirement).

The disadvantages of this version of the chimney are the considerable cost of the project and the complexity of the work. Firstly, the construction of this structure will require much more building material. Secondly, the chimney, if it is partially on the street, requires serious insulation measures, otherwise in winter, with temperature changes, condensate will form in the internal channels, which will significantly reduce the efficiency of the heater. Therefore, if this chimney option is chosen, then it would be more prudent to sacrifice the area inside the premises and bring the pipe along inner wall Houses.

Parameters of brick chimneys

The main sections of the brick chimney

A brick chimney is divided into departments that have an owl purpose and are named differently. These features must be immediately clarified so that in the future it will be easier to understand the description of the work on the construction of the pipe.

1 - Pipe head. Laying out this part of the chimney, the bricks are shifted into outside to get a kind of "visor", as if hanging over the lower sections, partially protecting the pipe walls from atmospheric precipitation.

2 - The neck of the pipe is located immediately below the head and has the same perimeter over its entire height, without protrusions, extensions or narrowing.

3 - "Otter" has more complex scheme masonry, as it has a protective function. Firstly, the laying of the "otter" hanging over the gap formed at the junction roofing material and the walls of the pipe, closes it from the penetration of precipitation, and forms a space for the installation of a waterproofing material. Secondly, its expanded walls become a guarantee of safety - at the place of passage through the roofing, due to the increased thickness, the necessary level of thermal insulation is created.

4 - A metal or other sheet (apron), mounted in the lower part of the otter, forms a kind of ebb, which closes the junction of the brick wall of the pipe and the roofing material.

5 - "Fluffing" - this expanded part of the pipe, located in the area of ​​\u200b\u200bits passage through the attic floor. The walls of the "fluff", like the "otter", have greater thickness, than others flat areas chimney - this is necessary for fire safety, since the attic floor very often consists of flammable materials, and they cannot be allowed to overheat.

6 - Roofing structure.

7 - A riser is a straight pipe section that has a flat masonry over its entire height and is located in attic space from "fluff" to "otter".

8 - Attic floor.

9 - An umbrella cap is often fixed on top of the head, which will protect the internal chimney channel from water and debris entering it.

You may be interested in information about what is

The main function of the chimney is to effectively remove combustion products from the combustion chamber into the atmosphere. To do this, the chimney is connected to numerous channels located in the furnace structure, with which it must interact harmoniously. If the stove and chimney are built correctly, in accordance with the developed parameters, then during the operation of the heater, good draft should be created inside the channels, which will contribute to the timely removal of smoke to the street. However, at the same time, this should not lead to the fact that the heat generated by it will fly out of the furnace literally “into the pipe”. In a word, everything needs a “golden mean”.

Cross section of the chimney channel

For selection correct parameters section of the chimney channel, you need to take into account the power of the furnace, as well as the size of the combustion chamber. The flue ducts will remain clean longer if their inner walls are made smooth, without protrusions and sagging of the solution.

For this reason, during the laying of bricks, the excess masonry mortar it is necessary to clean not only from the outer, but also from the inner walls. Some owners of houses equipped with fireplaces or stoves also use another way to achieve the smoothness of the walls of the channel - they install a ceramic pipe called an inlay inside the brick chimney.

The advantage of this design is not only that the inlay has absolutely smooth inner walls. It is round in cross section, that is, it has no corners, which means that the smoke flows will not encounter obstacles in their path and, at the same time, unnecessary turbulences and the “back draft” effect will not be created.

On the right in the illustration, the "ideal" movement of the flow of hot gases, which are in the pipe round section twist into a regular spiral and meet no resistance.

In addition, it is necessary to take into account the fact that chimneys with a large width, which are still installed in old houses, often have bad traction. This is due to the fact that the air heated in the furnace in large space inside the pipe, cools down quickly, which leads to the formation of condensate, which contributes to a decrease in traction, as well as smoke in the premises, and rapid soot overgrowth of the channel. To heat a stove with such a chimney design, you will need to use too much fuel. Therefore, it would be most rational to fix them by dismantling a wide upper part chimney, then narrowing the shaft and installing a round or square with rounded corners, ceramic, metal or asbestos insert into it.

Now from the form - to linear parameters. The size of the internal section of the chimney channel is one of the most important characteristics, since the efficiency of the furnace directly depends on this. The correct ratio of the power of the heater and the dimensions of the pipe section must be observed. Another guideline for determining the correct size of the channel can be the opening of the blower door - in any case, the cross section of the pipe should not be less than the blower hole.

The cross section of the chimney shaft, relative to the size of the combustion chamber window, can be determined as follows. For fireplaces with an open firebox, the size of the chimney opening is on average 1:10. However, depending on the shape of the section and the height of the pipe, this indicator may vary in one direction or another. Approximate values ​​of the cross-sectional area of ​​the channel (in percent) are shown in the table below.

Ratiof/F in % (f is the cross-sectional area of ​​the chimney channel;F is the area of ​​the combustion chamber window)

It is clear that in addition to the size of the furnace window, it is also necessary to build on the reasonable height of the pipe - it will look absolutely ridiculous, for example, a huge 10-meter pipe on the roof of a small squat country house.

The calculation itself is easy. According to the table, based on the height of the pipe and the shape of its internal channel, the optimal f / F ratio is determined. Then, based on the area of ​​​​the furnace window, it will not be difficult to determine the area of ​​\u200b\u200bthe chimney channel. Well, then, using geometric formulas, it remains only to bring the resulting value to linear dimensions - the diameter for round pipe or the length of the sides for a rectangle.

This calculation algorithm is implemented in the calculator below.

A chimney is an essential element of any heating system that emits combustion products during operation. A draft is created in the pipe, on the one hand, ensuring the flow of oxygen into the furnace, which is necessary to maintain the combustion process, and on the other, contributing to the removal of smoke and gases to the outside. In long-burning furnaces, the installation and operation of the chimney is carried out according to standard rules, although it has some peculiarities.

Of the variety of metal furnaces, installations with a long-term combustion function (convection furnaces) are in great demand and popularity. These ovens are easy to operate and very economical. They are equally good for little ones. country houses, multi-storey private houses, workshops, storage facilities etc.

The main features of these ovens include:

• The increased volume of the furnace, containing a large amount of firewood.
• Separation of the furnace into two chambers that perform different functions. Gas is burned in one, firewood smolders in the other.
• The presence of a special chipper inside the firebox that prevents the open flame from flooding into the chimney.

The combustion process itself is fundamentally different from the operation of an ordinary metal furnace. Firewood is ignited in the upper part of the furnace, air is also supplied here. The feed volume is regulated by a damper. The fire spreads down, and the intensity of the flame cannot be called strong, the process is more like smoldering.

As the firewood smolders, pyrolysis gas is also released, which moves into a separate chamber of the firebox, mixes with air and also burns out, further increasing the efficiency of the installation.

During the operation of the long-burning stove, less heat is generated, allowing you to maintain the temperature in the room at the same level. Firewood is consumed much less, and the combustion products entering the chimney have a low concentration of harmful substances.

Buleryan oven: advantages and disadvantages

Bullerjan is one of the types of long-burning stoves that works on the principle of convection.

The design was developed by Canadian inventor Eric Darnell in 1975, after which the rights to the patent were bought by German businessmen who launched the serial production of stoves under this brand.

The stove combines the functionality of a standard wood-burning firebox, a heater and a gas generator. Buleryan is able to work in two modes:

• Kindling. More air is supplied to the burning wood, which contributes to their rapid combustion and accelerated heating of the room.
• Gasification. The supply of oxygen is reduced to a minimum. Firewood gradually smolders, and the room warms up more slowly. In this mode of operation, one bookmark of firewood will be enough for 10-12 hours of continuous operation.