How to build long-burning stoves with your own hands? How to make a long-burning stove with your own hands? DIY solid fuel stove.

When the budget allows, you can purchase a long-burning stove manufactured at the enterprise. This option has an elegant look and can last a very long time. In addition, the unit is absolutely safe to operate. However, not everyone can afford such a purchase. And then the question arises about making such a stove yourself. It is also called pyrolysis. The creation process is relatively complex and requires strict adherence to all the necessary technologies and algorithms. First you need to thoroughly study how this device functions. You must have experience with metalworking and other turning skills.

Main characteristics and advantages of long-burning furnaces

Long-burning stoves, created independently, can operate on the following types of solid fuel:

• firewood;
• coal;
• sawdust.

The cost of fuel cells is low. For this reason they have become very widespread. The long-burning wood-burning stove has gained great popularity among home owners. It is created at home, called “bubafoneya”.

What is a long burning stove?

There may be slight differences in the designs of long-burning stoves. But the principle of their operation is similar - this is the generation of thermal energy during pyrolysis (not using the open flame method), when the wood is exposed to an impressive temperature with a limited amount of oxygen. And the fuel smolders, forming hot gas. It contains:

Pros and cons of long-burning stoves

The use of long-burning stoves operating on solid fuel in the heating system of premises helps eliminate almost all the shortcomings inherent in standard designs using similar fuel:

1. Pyrolysis units are characterized by higher efficiency when compared with classical modifications.
2. Long-burning stoves do not need to be constantly loaded with wood or coal.
3. The operation of the pyrolysis system can be automated.

A small caveat needs to be made regarding this last benefit. When a homemade heat-generating apparatus is used, there is usually no need for automation, since even one load of fuel cells guarantees uninterrupted operation for 20 hours.

Design features of pyrolysis furnaces

Combustion in a pyrolysis furnace is characterized by low dynamics and high efficiency. It is provided by air supply using a regulator. When the fuel cells ignite thoroughly (approximately 20 minutes after loading), you need to close the air supply hole. This minimizes the passage of oxygen.

The main contribution to heat generation in a pyrolysis furnace is made by flue gases, which are located in a special sealed compartment

The fuel smolders and is almost completely converted to gas. And the flue gases are concentrated in the ignition compartment. When they burn out, a lot of heat is generated. If you try to implement this method of combustion in a conventional stove, directing its operation to smoldering mode, you can cause serious damage to your own safety. In the best case, the gases will rush into the chimney. At worst, they will end up indoors, bypassing doors with weak seals.

Making a long-burning stove with your own hands

Before starting installation and assembly work, it is necessary to correctly calculate the operating mode of the furnace and its design, and then prepare all the necessary materials and tools. We will consider the furnace manufacturing process step by step, starting with the creation of a detailed diagram of the heating unit.

Calculation of furnace parameters according to drawings

To make a preliminary assessment of the upcoming scope of work and the configuration of the main elements of the pyrolysis furnace, it is necessary to study the general diagram of its structure.

For reference, we present a table of the dependence of the main parameters of the furnace on the diameter of its base

Table: thickness of the workpiece and height of the duct ribs for different diameters of the furnace base

When the diameter of the cylinder does not fit the values ​​​​indicated in the table, the thickness is calculated by proportions, focusing on the standard of the metal sheet (its thickness).

The air channels must be made rounded and arranged in a spiral. This will ensure optimal movement of flue gases.

Required tools and materials

A very important stage of preparation is the selection of necessary materials and tools. The key component is a cast iron barrel with a capacity of 200 liters. You can also work with a steel barrel. The main thing is that it has no defects or rust. If there is no suitable barrel available, you can use:

• element of a very thick pipe;
• sheet steel;
• massive fire extinguisher;
• unused gas cylinder.

The main requirement is wall thickness. It determines the service life of the furnace.

Other materials:

1. Metal products for making legs. Fittings, elements of small-sized pipes or channels are suitable.
2. Steel 5 mm thick. You need two circles that have the same diameter as the barrel.
3. Ready-made or self-made door.
4. The pipe is 10 cm in diameter and 15 cm long longer than the barrel itself.
5. A pipe with a diameter of 15 cm and a length of approximately 5 m. It is necessary for the chimney.

Tools:

1. Bulgarian. Instead, you can use autogen.
2. Ax and hammer.
3. Measuring instruments: level, plumb line, tape measure.

Selection of installation location

After installing the stove, they make a reflector, but plan this before measuring and welding. It helps to optimally direct heat flows so that the room is heated evenly. In addition, the reflector seriously increases the level of safety during the heating process.

The area intended for installation of the furnace must not violate any of the fire safety criteria, since the hot furnace body is a potential source of fire. And this is what it becomes when the user violates the operating rules of this unit by incorrectly calculating the amount of sawdust or firewood.

The oven should not be placed near walls or any flammable objects. Sufficient space should be maintained around it. For example, the distance to wooden walls cannot be less than 25 cm.

Even before the assembly process, it is necessary to select a workspace. All stages of production will take place there. The following criteria apply to the premises:

• availability of power supply;
• availability of the necessary space;
• powerful sound insulation;
• protection from precipitation;
• ability to store workpieces.

Soundproofing is needed in order not to cause discomfort to neighbors. After all, the work turns out to be quite noisy. You can do without this insulation when the work area is located far from residential buildings.

Step-by-step instructions for self-assembly of a long-burning stove

The sequence of actions is as follows:

1. Let’s assume that we use what is available in private garages or workshops. These are old gas cylinders. They are prepared for work as follows: the upper side of the structure is carefully cut off. The formed element will become the basis. For cutting, a grinder or autogen is used here.

   The top part of the gas cylinder is cut off and a window is made for loading firewood.

2. After cutting the top side, a side hole is made in the cylinder body. It is needed to load fuel into the furnace during its operation. Based on the parameters of the hole, you need to make a door and then put it in place. The door should close this hole very tightly.
3. Below the marked hole, another smaller one is made. Ash will be removed through this compartment. It also functions as a blower.
4. When the cylinder is ready, the next stage begins: preparation of the starting material. Here we take a pipe with a diameter of 10 cm and a metal sheet. A circle of slightly smaller diameter than the balloon is prepared from it. A hole is created in its center for the working pipe. The circle is put on it and welded.

   A pipe is welded onto a circle slightly smaller in diameter than the cylinder and a lid is obtained with which to cover the burning firewood

5. 2-3 channels are welded onto the lower side of the circle. Their role is to increase the mass of the lid.
6. Then the circle is lowered into the prepared (cut) gas cylinder. After this, holes for the pipe are created in the lid. After which the cover is placed in its position and welded.

Video: do-it-yourself bubafonya from a gas cylinder

Features of manufacturing a sheet metal stove

Let's consider working with a sheet metal base. In his work, the master must precisely:

1. Calculate the parameters of all structural components.
2. Mark sheet material.
3. Process all elements of the device.
4. Carry out welding operations.

Required conditions:

Modernization of the furnace, increasing efficiency

There are three main ways to increase the efficiency of a stove: one of them is related to the chimney, the second is related to the fuel, and the third is related to operating conditions.

Chimney design optimization

For the chimney, as already noted, a pipe with a diameter of 15 cm and a length of 5 m is used. If you install a smaller pipe, especially in diameter, then it will not cope with the resulting loads. And the furnace itself will operate with reduced efficiency. To adjust the draft, a valve is installed in the pipe. A door is created at the bottom of the chimney for easy cleaning.

Condensation forms and accumulates in any pipes. And in pipes during pyrolysis it turns out even more, since the gases, having parted with all their heat, have negative temperatures at the outlet. This trend becomes the reason for high-quality insulation of pipes. The sandwich technology copes with this task perfectly. Its essence: a second one is introduced into one pipe, and a thermal protection layer is made between them.

You can also make a sandwich pipe with your own hands by wrapping the chimney with insulating material and protecting the structure with an external pipe

In areas where pipes pass through the roof, it is necessary to perform thermal insulation using a metal box filled with insulation. A deflector is placed on the head of the pipe. It prevents precipitation from entering the system and also protects against the effects of wind.

If the installation site for the stove is a fireplace, there is no need for a reflector. When the stove is located in a room, the surrounding masonry performs two functions:

1. Protective screen for walls and things.
2. Heat accumulator.

Since the body of the structure is metal, the oven quickly heats up and cools down. Cooling occurs immediately after the fuel burns out. Therefore, a brick screen created on three sides of the stove accumulates heat and releases it over time. You can use corrugated sheets or a smooth metal sheet as a reflector.

What fuel is better to use in long-burning stoves

The efficiency of the furnace also depends on the fuel used. It is best to use dry logs. But since the stove is homemade, you can save on fuel. The device can even work on waste made from natural materials.

• cones;
• wood chips;
• sawdust;
• nutshell;
• straw.

Coal gives a good combustion temperature. But its use is justified when the oven is made only of materials with a decent thickness. Otherwise, such a unit will quickly burn out. A table showing the specific heat transfer of various materials can serve as a guide.

Table: specific loading coefficient and specific heat transfer of various types of fuel

Operation of long-burning furnaces

At first glance, it may seem that to fire a pyrolysis furnace you just need to throw firewood into the combustion chamber. This is just a superficial impression. It is important to do the following:

1. Remove the cover, take out the pressure circle and pipe. Place fuel on the bottom of the stove. The filling limit is the opening of the chimney pipe. Fuel elements are stacked as closely as possible to each other. Light small branches are thrown over them. And they are covered with a rag soaked in kerosene. You can also place paper.
2. Then the pressure circle must be returned to its place, and the lid must be closed. When the unit flares up, you need to close the damper that conducts the air flow. And she will remain in this position for a long time.

When creating a chimney, be sure to provide convenient ways to clean it. It is best if the structure can be quickly disassembled. When a composite chimney pipe is made, its parts are connected so that the joints are located in the opposite direction compared to the moving gases.

Cleaning and repair of long-burning stoves

If the stove is used incorrectly, its performance may deteriorate and efficiency may decrease. Therefore, periodically check the device for cracks and other defects. It is especially important to study the areas around the perimeter of the combustion chamber door and stove. If serious cracks are found, the defective parts must be replaced. Small gaps can be filled with sealant.

All burnt and cracked parts of the stove must be replaced in a timely manner.

Video: long-burning stove - cleaning and checking

If you have a small house, a garage, or just need to efficiently heat a utility room, a long-burning stove is the best option. Having some experience working with metal and welding skills, such a device can be built in 1–2 days. If the result is successful, you will be able to save money and gain satisfaction from the process of making a useful thing with your own hands.

The problem of conservation and economical use of energy resources is currently very acute. City residents usually do not have many opportunities to save money, since all apartments are connected to a central heating system.

Long-burning wood stove in the country

Prices for housing and communal services for all apartments of equal size will be the same, so everyone finds themselves in the same conditions. Another thing is the private sector with an individual heating system. This is where you can be smart and have room for a creative approach to solving a problem. In this article we will learn that long-burning wood-burning stoves for summer cottages are one of the most optimal options for getting out of this situation.

Actually, the efficiency of our home heating will depend on two main factors:

• Quality of insulation (thermal insulation) of the walls and windows of the building;
• The efficiency with which our heating installation (furnace or boiler) uses fuel.

The purpose of this article is to introduce you to one of the types of economical and productive wood-burning stoves that allow you to ensure the most complete combustion of logs. These heating installations are called pyrolysis furnaces. Every year their popularity is increasing, so many are thinking about building such a heater with their own hands. How long-burning pyrolysis furnaces work, their internal structure, as well as instructions for self-assembly - you will learn all this by reading our article.

The main physical phenomenon, without which it is impossible to imagine the operation of any furnace, is the oxidation of various substances by oxygen contained in the air. Fire, tamed by our ancestors millions of years ago, has become so familiar today that we don’t even think about how combustion occurs, with which each of us has been familiar since childhood. The seemingly simple question “how does wood burn?”, in fact, requires a separate explanation. After all, without understanding the basics, we will not be able to understand how economical pyrolysis furnaces work and why they are so good and economical.

Actually, the formation of a flame occurs in several stages:

1. First, the wood heats up and dries, releasing water vapor into the environment, which prevents fire from starting. This requires an external source of energy, which is usually flammable paper, kindling liquid, or a pile of small burning wood chips.
2. Firewood, which from a chemical point of view is a complex organic structure, consists of three main elements: carbon, hydrogen and oxygen. When heated, wood disintegrates, and these components, in the form of various simple gaseous compounds, begin to be released into the surrounding space. The general name for all substances formed during fuel heating is pyrolysis gases, and for the process itself is pyrolysis.
3. At the next stage, the wood decomposition products ignite and accelerate the pyrolysis of the remaining logs more and more, providing the fire with fresh fuel.
4. In the end, the tree burns, leaving behind some of the coals that did not have time to react with the oxidizing agent.

Actually, the idea that made it possible to build long-burning furnaces is to ensure the most complete decomposition of fuel in such a way that after its use there is practically no unburned waste left. To do this, it was necessary to slow down the pyrolysis as much as possible so that the entire volume of firewood would gradually and completely disintegrate into pyrolysis gases.

Why are stoves called long-burning stoves?

A long-burning stove is quite easy to distinguish from a regular one. The fact is that the implementation of the idea of ​​high-quality and complete pyrolysis required the introduction of not one, but two combustion chambers into the stove design. In the first, the firewood slowly smolders, emitting a gas mixture of methane, hydrogen and other components. Smoldering is ensured by an artificially created lack of oxidizer supplied to the firebox. Further, entering the second chamber, the gaseous pyrolysis mixture begins to burn fully, providing heating to the room in which the boiler is installed. Often, the secondary firebox is also additionally blown with air using a special fan. This ensures the most complete oxidation and combustion of the entire volume of gases, and leads to a significant increase in the efficiency of the entire heating installation.

Pyrolysis ovens are often also equipped with a separate cooling circuit, which evenly distributes heat throughout all rooms in the house. Such a heating boiler copes well with even the most severe winter frosts, providing high-quality heating of the entire living space. An example of a block diagram revealing the internal structure of a pyrolysis stove with a water block can be seen in the figure below.

Advantages and disadvantages of pyrolysis furnaces

Nothing in this world is perfect, so even long-burning wood stoves are not without their drawbacks. The main ones are the following:

• The price of modern high-tech long-burning pyrolysis furnaces with good efficiency indicators will be quite high. However, you can save a lot of money by designing a heating device yourself.
• Pyrolysis boilers of industrial production often require additional uninterrupted power supply to their auxiliary units: air injection systems (combustion chamber pressurization), water heating circuit pumps, sensors, etc.
• Long-burning stoves are more finicky in terms of moisture requirements for wood logs. Insufficiently dried firewood placed in the firebox of a pyrolysis boiler can easily go out, stopping the operation of the entire heating system.
• Compared to gas (electric) boilers, boilers or water heaters, long-burning stoves are significantly larger in size and also require additional free space for storing firewood.
• You will have to add fuel to the pyrolysis boiler manually; this operation cannot be fully automated 100%.
• A more complex water circuit design compared to other types of heating installations. The fact is that too supercooled coolant, returning from the batteries to the boiler heat exchanger, can interrupt the smoldering of the wood and extinguish the firebox. To avoid such a situation, you have to install an additional pipe (the so-called “bypass”), which allows you to mix already heated water with cold water. Naturally, as the complexity of the heating circuit design increases, the total cost of the entire device also increases.

At first glance, the list of disadvantages of long-burning wood stoves seems very impressive. And many people have a logical question: why is this type of stove so popular and in such good demand? The answer is simple and obvious: all the disadvantages of a pyrolysis installation are more than compensated by the advantages that the owner of such a device receives:

• Fuel energy is used almost 100%. All loaded firewood will burn to the ground, completely transferring its heat to the heated room. High-quality industrial-made long-burning stoves have fantastic efficiency indicators, up to 90 percent. For greater clarity, we provide a table below that compares the operating efficiency of different types of boilers.

• Long-burning wood stoves are convenient and easy to maintain, and produce almost no waste. There is nothing left of the firewood except a handful of ash.
• Environmental friendliness of the heating system. With full pyrolysis combustion, only water vapor and carbon dioxide are released into the atmosphere. During operation of a high-quality pyrolysis oven, you will not feel any extraneous unpleasant odors, compared to a conventional oven. This is explained by the fact that the source of such aromas are unburnt complex organic compounds. In a long-burning furnace, fuel oxidation occurs 100%, so it can easily be heated even with industrial waste.
• One “filling” of logs is enough for 10-15 (and sometimes more) hours of continuous operation. No ordinary wood stove can burn for that long.
• The heating system based on a pyrolysis boiler very quickly warms up the house and enters operating mode.
• The power of a heating device using the pyrolysis effect can be easily and smoothly adjusted, just like a gas or electric one. Unlike conventional solid fuel installations, in a long-burning furnace the main heat is generated by gas burned in a separate chamber. Accordingly, by controlling the level of oxygen supply to the firebox, we can easily change the heat release of the entire system.

Choosing a long-burning stove for a summer residence

Actually, having decided to acquire a long-burning stove, the future user faces the question: which one is better to choose? If you are planning to make a pyrolysis boiler with your own hands, then the available options will be limited only by the materials you have, as well as your engineering ingenuity and imagination. We will tell you more about how to make a long-burning wood stove for a summer house later, but now let’s try to give some useful tips to those who decided not to bother and buy a ready-made heating system.

The main parameters that should be followed when selecting available boiler models are:

• Limitations of the budget allocated for the purchase of a gas generator furnace.
• The area of ​​the house that is to be heated using a pyrolysis unit. Depending on the characteristics and configuration, long-burning stoves can heat from 80 to 250 square meters of living space.
• Operating time of the unit when fully loaded with fuel. There are three subcategories of gas generator boilers: with a minimum operating time (up to 4 hours), with an average heating period (up to 8 hours) and, in fact, long-burning furnaces (they burn at one gas station for more than 8 hours).
• Other technical and functional characteristics of the device.
• Appearance and design of the pyrolysis furnace. Functionality and efficiency are, of course, a priority, but do not forget that a gas generator boiler is also an element of the interior of the house. It is highly desirable that the heating installation fits harmoniously and naturally into the interior space of the room in which it is located.

A few words about the main characteristics according to which long-burning pyrolysis boilers are classified. Based on materials of manufacture, they are distinguished:

The first two are suitable for those who want to get the most compact device, and the last type will appeal to lovers of the classics. Such a brick stove can easily become a highlight in the interior of any home.

According to the method of loading firewood: manually or semi-automatically. The second type will cost more, but will reduce labor costs for boiler maintenance.

Pyrolysis plants can be equipped with various “add-on components”, so they should also be classified according to the presence of additional functional units. They can be a hob or a special transparent fireproof door that can turn an ordinary solid fuel heater into a full-fledged and aesthetic fireplace.

Naturally, you should understand that you will have to pay extra for any design and technological delights. It is for this reason that prices for long-burning gas generator stoves vary in a wide range from 10 to 100 thousand rubles and above.

Installation of a purchased gas generator furnace

Installation of a finished industrial gas generator boiler requires special attention, so we will devote a separate section of the article to this issue. Actually, the general connection diagram for a pyrolysis furnace with a water circuit looks something like this:

It should be noted that this is only one of many options for wiring the heating circuit. Different manufacturers may offer their own schemes, which will differ in some ways. Therefore, in each specific case, carefully study all technical documentation accompanying the device. As for this scheme, the so-called three-way valve deserves special attention: it is responsible for mixing hot water into cold water and preventing the stove from overcooling.

The cold water heating mechanism can be implemented differently. Below you can see two more possible connection diagrams for pellet pyrolysis boilers:

The combustion room in which they plan to place the boiler must meet certain requirements:

• be spacious and have high ceilings. Preferably from eight square meters; area and with a ceiling height of two and a half meters;
• have a special platform for installing the boiler;
• the ceiling, like the walls themselves, must consist of a material resistant to temperature and fire;
• the room must be equipped with at least one window opening;
• the distance from the wall to the front of the boiler should be about two meters;
• it is advisable to surround the boiler with an additional brick jacket;
• the room must have a chimney and a ventilation system (exhaust).

In general terms, the boiler installation algorithm is as follows:

Making a long-burning stove with your own hands

We have figured out the main guidelines in choosing a ready-made long-burning stove for a summer house, and now let's find out how to make such a device at home yourself. In the next two sections of the article we will look at the manufacturing technology of both metal and brick pyrolysis boilers. It should be noted right away that you cannot do without minimal bricklaying skills, as well as the ability to work with a welding machine, so get down to business only if you are 100% confident in your abilities.

Pyrolysis oven from improvised means (barrel, cylinder, thick-walled pipe)

The easiest and cheapest way to assemble a gas generator stove is from an old cylinder or metal barrel. Such a device will not have a particularly attractive appearance, but it is quite suitable for heating a summer house, garage, utility room or greenhouse. In addition, this type of stove is very mobile and can easily be moved to any other place.

Materials and tools for work. Workplace requirements

In addition to all of the above, we will need:

• Sheet steel from which we can cut a circle equal in diameter to the body of our furnace;
• Pieces of metal profile for making a pressure piston;
• Stove door, which you can order ready-made or make yourself;
• Two metal pipes. One with a radius of about 5 centimeters and a height equal to the height of the stove body +15 centimeters from above, and the second with a radius of 7.5-8 centimeters and a length of about 5 m. The first will be useful in the manufacture of the pressure piston air duct, and from the second we will make a chimney.

Having obtained all the necessary materials, we begin to search for a suitable workplace to carry out all the necessary installation operations. The room in which we will assemble the stove must meet a number of requirements, namely:

• Have good ventilation so that welding can be used in it;
• Good lighting at any time of the day;
• Have an uninterrupted power supply;
• Have reliable noise and sound insulation. During the installation process you will have to use a grinder and welding, and insulation will allow you to disturb your neighbors to a lesser extent;
• Be spacious enough so that we can safely store all the structural parts and tools there;
• Be protected from any atmospheric influences that could lead to damage to the metal parts of the oven.

Instructions for assembling a homemade gas generator stove

Video. How to make a pyrolysis oven from a gas cylinder

Rules for igniting a pyrolysis furnace

Remember that when installing a long-burning gas generator stove in any room, you must strictly adhere to the rules for its use:

• The body of the heater reaches significant temperatures, so keep away any items that may spontaneously combust or are heat sensitive.
• Leave enough free space around the gas generator boiler. Furniture cannot be placed next to it, and the walls themselves can also be damaged under its influence. It is advisable to build a special protective jacket made of bricks around the stove. Brickwork will not only protect things around it, but will also help retain heat for a longer period.
• When cleaning the firebox of a homemade stove, leave a certain layer of ash after each time. It will serve as a protective cushion and prevent rapid burning of the lower part of the gas generator boiler, which can lead to breakdown of the entire device.

Laying a brick pyrolysis furnace

A gas generator furnace can be assembled not only from metal parts, but also laid out using bricks. Before we begin to directly consider this issue, we will need to understand the meaning of some fundamental terms that characterize the qualities of materials for furnace work. Actually, there will be only 3 such concepts: heat resistance, heat resistance and fire resistance.

Heat resistance is the ability of a material to withstand heating to high temperatures and subsequent cooling. During such thermal changes, the substance must not change its structure, geometric shape and chemical composition. At the same time, over the entire range of operating temperatures, heat-resistant compounds must withstand the initial design physical loads and not collapse.

As for heat-resistant materials, their main advantage is the ability to maintain initial mechanical characteristics when heated or cooled. The coefficient of thermal expansion of such compounds practically tends to zero. Heat-resistant materials are the basis not only in the furnace industry, but also in the production of mechanisms and machines designed to work in extreme conditions.

Refractory are heat-resistant or heat-resistant substances that are resistant to aggressive chemical environments. In the stove business, they are used to construct chimneys, the inner surface of which is constantly exposed to gaseous combustion products, which often settle during cooling in the form of caustic condensate.

Materials and solutions used for laying various elements of the furnace

Since individual elements of the stove structure carry different functional loads, the brick (as well as the mortar) must be selected individually for each of them. Let's look at everything using the example of a classic wood-burning stove.

1. The “pillow” (also called the “root”) of the stove is the basis of the foundation of the stove made of reinforced concrete. It is poured in such a way as to be mechanically independent from the foundation of the entire building. This condition must be met without fail, since the stove and the house differ in the rate of shrinkage. Filling is carried out in the usual way; there are no distinctive features in this process.
2. A layer of waterproofing material. It can be constructed from ordinary roofing felt, folded in a couple of layers on top of the stove cushion.
3. Furnace foundation. Its laying requires a careful and scrupulous approach. An error when assembling the foundation will lead to the fact that the entire structure will have to be rebuilt. Red solid brick - this part will not feel strong temperature effects. Kiln mixtures should be complex, cement-lime, with three or more components.
4. Fireproof blind area with a heat-insulating layer. It is made from a mineral sheet of asbestos placed on top of a sheet of iron. The third, top layer, completes the structure with a felt cloth treated with clay impregnation (liquidly diluted clay, the so-called “clay milk”).
5. The main part of the “body” of the stove, which performs the function of a heat exchanger. The operating temperature of this element very rarely exceeds the threshold of six hundred degrees Celsius, but it is constantly exposed to acrid smoke and the chemically aggressive compounds it contains that can settle in the form of acid condensate. Therefore, the brick for this part of the stove requires a specialized stove, red, solid ceramic type M. The mortar, in turn, is clay, one-component.
6. Stove firebox. In a pyrolysis furnace, it will consist of several chambers, each of which is subjected to a very powerful thermal effect. The temperature inside the firebox can reach values ​​of up to one and a half thousand degrees. You need a special brick, the so-called fireclay, and you need a clay-fireclay mortar.
7. The “source” of the chimney pipe. It must withstand the same impacts as the furnace heat exchanger, so the materials that need to be used for its laying are similar to those in point No. 5.
8. The chimney fluff is a structural element designed to provide an elastic connection between the chimney and the ceiling, preventing its possible subsidence. The brick here needs a stove M150, and the mortar is lime.
9. A fire separator is an iron box, inside of which there is a layer of non-flammable heat-insulating material.
10. The main part of the chimney pipe. They lay it with ordinary red brick, since it is not subject to strong thermal or chemical influences. The solution is lime type.
11. The chimney fluff, which completes the stove structure, is also made from the same materials.

Preparation of materials and tools for masonry

As it has already become clear to you from what you read above, for the stove masonry we will need to stock up on three types of bricks:

• red solid - it will be used to make the foundation and part of the chimney
• red ceramic stove M150 – for assembling the main part of the stove body
• fireclay for laying combustion chambers

Further, we cannot make the foundation of the furnace without cement. Accordingly, it also needs to be purchased. In addition, we additionally buy roofing felt, sheet steel and various auxiliary stove accessories: doors for adjusting the air supply, a hatch for loading firewood, etc. The quantity and type of materials chosen will depend on the specific stove laying scheme that you choose for yourself. We will consider one of them in our article, but you should not limit your flight to your engineering imagination only within the framework of a single instruction.

As for stove solutions, you can easily prepare them yourself. This process is quite labor-intensive and takes some time, but it allows you to significantly save on materials and reduce the final cost of creating a brick pyrolysis furnace. This issue is discussed in more detail and with all the necessary instructions in the article. .

The tools we will need are:

• Master OK
• Roulette
• Construction level and plumb line
• Hammer
• Containers for preparing furnace solutions and pouring foundations
• Shovel
• Sieves for sifting sand and straining clay

Making the foundation of a brick gas generator furnace

Long-burning stoves are distinguished by the fact that they must quickly heat up and switch to operating mode within a minimum period of time. For this reason, the foundation of a gas generator stove must be placed at least at a distance of 70 centimeters or more from the foundation of the building itself. In addition, it is advisable to fill the gap between both foundations with sand.

Basic rules for laying a pyrolysis furnace. Ordinal scheme

When starting to lay a gas generator furnace, remember that you must strictly adhere to the following rules:

• Each of the furnace elements must be assembled from the appropriate type of brick that will withstand all temperature and chemical influences. We have already written about this above.
• The laying should be carried out clearly according to the chosen order plan in order to avoid mistakes and the need to redo the work again.
• After every 2-4 rows, be sure to check the quality of the masonry with a level or plumb line. You don’t want the oven to turn out crooked, do you?
• In each row (as well as between rows), it is necessary to perform a complete dressing of the seams.
• The width of the joints in homogeneous brickwork should be about three millimeters. At the junctions of fireclay and red bricks, the size of the seams must be increased to six millimeters. The same rule applies to connections between brick and steel elements.
• Seats for various doors and valves should be made with a small margin, taking into account the possibility of thermal expansion of parts. Between the metal and the brick, it is imperative to place asbestos gaskets, or intermediate layers of special building mixtures based on sintering compounds. For example, you can use fireclay or silicone for fireplaces - these materials can withstand high heat and, at the same time, ensure the tightness of all connections of the body and stove fittings.

Finally, as an example, we will give you one of the possible row diagrams of long-burning furnaces. Naturally, before starting construction, you must definitely evaluate the dimensions of the room and the size of the space that you plan to allocate for the gas generator boiler. In accordance with these initial parameters, you should choose the scheme that suits you. It will be quite easy to estimate the size of the future heating installation, because the dimensions of one brick are standard and for a solid red brick they are 25x12x6.5 centimeters.

As an additional bonus, we also invite you to watch the video, which shows one of the possible options for making a brick pyrolysis oven yourself. The author demonstrates step by step each stage of stove laying, and also conducts a practical test of his device in action.

Video. Do-it-yourself long-burning brick oven

Solid fuel stoves running on wood have one serious drawback: it is very difficult to automate the combustion process, and for some designs it is impossible. From time to time you have to take a break from your work and add firewood, which burns out in about an hour. To extend the operating time of the furnace on one load, the furnaces are equipped with a long-burning mode.

Wood combustion is a complex physical and chemical process that occurs in several stages. When ignited, while the temperature in the stove is low, the wood heats up and darkens. At temperatures above 200 degrees, pyrolysis begins - decomposition under the influence of temperature into solid residues and pyrolysis gases. These gases themselves are flammable because they contain hydrogen, carbon monoxide, organic vapors and carbon in the form of soot. It is the combustion of pyrolysis gases that produces a bright flame with a high temperature.

In a conventional furnace, complete combustion of pyrolysis gases does not occur due to a lack of oxygen. In long-burning furnaces, a separate chamber or combustion chamber is intended for afterburning of pyrolysis gases, where they are enriched with atmospheric oxygen. Thanks to this, fuel is burned more completely, less soot and other harmful substances are released into the air, and the efficiency of the stove increases.

To avoid excessive temperature in the wood pre-combustion chamber, air access into it is limited. The firewood begins to smolder, releasing a large amount of pyrolysis gas. Due to the slow smoldering of firewood, the operating time of the stove on one load increases significantly, in some cases reaching 6-8 hours. This phenomenon is called the “long burning mode”.

Long-burning sawdust stove: video

Advantages and disadvantages of long-burning stoves

Like any other unit, such ovens have their pros and cons.

The undeniable advantages include:

• economical consumption of firewood;
• high efficiency, up to 85-90%;
• versatility in the choice of fuel, firewood, waste from woodworking enterprises, sawdust, and pellets are suitable;
• small sizes;
• ease of control - using an air damper;
• simplicity of design, thanks to which it is easy to make a long-burning stove with your own hands.

Long-burning stoves are not without their disadvantages:

• during combustion, condensate is released, on which soot is actively deposited in the chimney, therefore special requirements are imposed on the chimney design - it should not have corners, bends, its design should be as accessible as possible for cleaning;
• To switch to the long-burning mode, the stove must first be heated in the usual mode to warm up the stove itself and the chimney, otherwise the combustion process will stop.

All the described features of long-burning stoves are relevant both for industrial heating units and for home-made stoves.

You can increase efficiency by adding to the stove, as shown in the video.

Design of long-burning furnaces

Long-burning stoves have design features. They consist of two chambers or combustion zones, in one of which pyrolysis of wood occurs, and in the other, afterburning of wood gases occurs. The location of the cameras relative to each other may be different.

In some models, fuel is loaded from above; as a result of primary smoldering, the firewood compacts and settles, and gases enter the afterburning chamber, which can be located either below or through a partition on the side of the first chamber. Such stoves are often equipped with blower fans to direct the draft into the desired channel.

In other models, the pre-combustion chamber is located at the bottom, and the pyrolysis gases rise into the upper chamber without forced draft. Such stoves do not require a fan, but their loading chamber volume is usually smaller.

To regulate the combustion intensity, an air supply channel with a damper is provided. It can also have different shapes and depends on the type of stove. To compact the fuel and make smoldering more intense, some stoves are equipped with a weight that lowers as the wood burns. Usually they have this design.

Application of pyrolysis furnaces

Long-burning stoves using wood, pellets or sawdust are often used to heat utility rooms and workshops, garages, and greenhouses. They can also be used to heat a house, but it is necessary to ensure that the stove is sealed, as carbon monoxide may be released.