Having decided to heat the home with wood and coal, the homeowner does not want to work as a fireman and run to the boiler room every 3-4 hours. This is where the demand for solid fuel boilers arises long burning, which can work on one bookmark for 6-8 hours or more. How to choose the right heating unit, read our publication.

Operating principle of long-lasting heaters

Many Russian, Belarusian and even Polish companies have caught on to the trend and have launched the production of long-burning domestic heat generators operating on solid fuel. Moreover, half of them give the buyer incorrect information, adding the characteristic “long-term combustion” to the name of an inexpensive wood-burning boiler that works for a maximum of 6 hours from one tab.

Operation of a conventional heater requires constant preparation of firewood

To avoid getting scammed attractive price, and to choose a thermal unit with real indicators, you should understand what the duration of its operation depends on. There are 3 factors at play here:

1. Firebox capacity. The more wood and coal that enters the heat generator chamber, the longer they will burn.
2. Fuel combustion efficiency (COP). Economical boiler with high efficiency will throw less thermal energy into the pipe, and the heating system will receive more. Accordingly, the consumption of firewood will decrease.
3. Availability of automation and forced air supply, turned on only when necessary.

Reference. Despite the assurances of manufacturers, the efficiency of the vast majority of solid fuel heaters of classical design is 75-77%. The real indicator of pyrolysis and pellet units is not much higher - 80-82%.

The operating principle of the heating system is based on a large supply of fuel and its complete combustion within 8-12 hours. A long-burning solid fuel boiler should not operate in the notorious slow-smoldering mode, as advertising assures us. The reasons are as follows:

• smoldering firewood produces little heat to heat a private home;
• the efficiency of heat transfer from the combustion chamber to the water jacket decreases, as a result, the efficiency drops to the level of an air stove - a potbelly stove.

Hence the conclusion: from the user’s point of view, the best long-burning boiler should have a decent-sized firebox and modern automation, other factors do not have much influence. We will clarify the capacity of the fuel chamber further.

Fan and electronic boiler control unit

Review of long-burning thermal units

Practice and reviews from homeowners on forums show that the following types of boilers should be included in this category:

Note. For efficient use of fuel, all of the listed varieties must be equipped with a turbocharger - a fan or a smoke exhauster. Its launch and performance are controlled by an electronic unit that reads temperature sensors.

The advantage of a homemade boiler is its relatively low cost and the ability to take into account your wishes. The wizard will help you choose a heater design and make a fuel chamber required sizes. If you know electric welding, you can make the unit yourself according to the drawings provided.

How to choose a classic boiler

A traditional direct combustion heat generator equipped with a blower fan is a completely affordable and reliable option for the average owner of a private home. The unit operates according to a simple scheme:

Note. Wood heaters, equipped with a mechanical draft regulator instead of electronics, are not very economical. The fact is that the chain drive does not close the vent tightly and air penetrates into the chamber, causing the wood to burn slowly.

Now let’s talk about how to compare the operating time data given in the product data sheet with the actual size of the camera. If the volume of the firebox is less than 50 liters with a power of up to 30 kW, then you have a regular boiler that requires loading every 4 hours.

Classic and long-burning pyrolysis boilers have a firebox of 100 liters or more with a similar power. This is a sure sign that from 1 load of wood the heat generator will work for about 8 hours, coal - 12-15 hours.

In this design, flue gases make 4 passes in the heat exchanger

When choosing, pay attention to the design of the heat exchanger. It is better to buy a boiler installation with a developed structure of smoke pipes or channels, where hot gases make 2-4 revolutions. Giving as much as possible thermal energy before exiting, combustion products increase the operating time from 1 load.

Top combustion units

These boilers are record holders in terms of firebox volume and combustion duration. The well-known Lithuanian-made Stropuva thermal unit with a power of 20 kW has a chamber of as much as 260 liters. Accordingly, the instructions for its operation provide correct information: when loaded with firewood, “Stropuva” burns for 15-24 hours, and with coal – up to 3 days.

The operating principle of the heat generator is as follows:

1. The cylindrical combustion chamber is filled with fuel, pressed down from above by a pipe with a load. After ignition, the door closes and the fan starts, as described in the previous section.
2. Air is forced into the chamber through a pipe from above, so the combustion zone is also located in the upper layer of fuel.
3. As the mass of firewood (or coal) burns, it sags, and the pipe with the load goes down next until it reaches the grate. The automation operation algorithm is the same as in a traditional heater.

Note. These boilers repeat the principle of operation of the universal one. The design is distinguished by a water jacket and the presence of automation.

You need to understand that top combustion is not the decisive factor that increases the operating time of the heat generator. Main role A decent amount of firebox and automation play a role here. But judging by the reviews of real homeowners, boilers such as Stropuva, ​​Swag and the like have significant disadvantages:

• due to the design of the load in the form of a cross, part of the fine fuel sticks from the inside to the walls of the combustion chamber;
• until the first load of coal or wood burns completely, a new portion cannot be added (the entire mass of fuel will ignite, and not the top layer);
• Due to the size and depth of the chamber, it is problematic to lay a small portion of firewood in order to quickly heat the home from dampness.

An additional disadvantage of heaters is the reduced threshold for the maximum operating pressure of the coolant. If in classic TT boilers the limit is 3 Bar, then in Stropuv it is only 2 Bar.

Automated pellet heat generators

A pellet boiler is the ideal version of a long-burning unit, but it is also the most expensive. It is highly efficient and is loaded once a week. The heater consists of two main blocks - a boiler body with a water jacket and a pellet burner with a fuel hopper and an electronic control unit.

The burner, controlled automatically, ignites and goes out independently at the command of the temperature sensor. Some products from German and other European brands are capable of changing the intensity of the flame (perform modulation). Therefore, from the point of view of safety, efficiency and duration of operation, a pellet boiler is the best option of all that exist.

Note. There are coal boilers of a similar design on sale, but they are demanding in terms of quality and fuel fraction. Watch the video to see how pellets are burned automatically:

We have already described above how to choose the right heating unit according to the size of the firebox. Point two: pellet automated installations are best suited for the role of a long-burning boiler, and top-combustion heaters take third place due to design and operational shortcomings.

To make a successful purchase, be sure to consider the following factors:

If you plan to heat with coal, then when choosing, pay attention to the grate - it should be all-metal. Hot coal sticks tightly to water-filled grates and is quite difficult to clean. The expert will give you a few more recommendations in his video:

Conclusion

When deciding to buy and install a TT boiler with long-term burning of wood or coal, consider the cost factor. The price of a quality product is much higher than 250-300 USD. That is, what they ask for for steel units of unknown origin. A good homemade boiler with a power of up to 30 kW will cost about 550 USD. e., and the factory one - at least 900 USD. e.

Among the huge number of species heating equipment, presented on the market, one of traditional options for use in a private home is a long-burning boiler. Using the most modern scientific developments, engineers were able to build a boiler that can operate for up to 7 days on one load! This is not fantasy, this is already reality! Despite the rather large dimensions of the device and its bulkiness, this is the most practical and economical solution for heating a large area today!

A long-burning boiler can be used as the main combustion source, which explains its great popularity in many remote areas of the country where there is no other option for heating a home.

Unlike a classic boiler, where heat is released by the flame during fuel combustion, a long-burning device works according to a completely different scheme. The long-burning boiler is a completely new and improved design.

In conventional TT boilers, one load of firewood or coal ensures combustion for 6-7 hours, which is not very economical and requires constant monitoring in order to maintain optimal temperature regime. Long-burning appliances can maintain heat for 7 days with one load of firewood or coal.

What accounts for this difference in raw material consumption and how is this productivity achieved? This is what we will talk about in this article.

Solid fuel boilers appeared relatively long ago, but all of them, regardless of model and manufacturer, had one significant drawback. Fuel had to be constantly added as it burned. It was ineffective and not economical. This situation continued exactly until 2000, until the Stropuva company found a way to eliminate this problem. It is to engineer Edmuntas Štropaitis that we owe the invention of the long-burning boiler.

Today, this is the most practical and functional device for heating a private home or cottage, the performance level of which reaches 70 and sometimes 100%. But, unlike classic pyrolysis boilers, which are also characterized by good efficiency, such units can maintain heat for 7 days with just one batch of fuel!

What are its main technical features and why is this device so economical and effective?

The operating principle of a long-burning solid fuel boiler is similar to pyrolysis units. The main heat is generated not from the combustion of wood or coal, but from gasification solid fuel. The combustion process takes place in a closed space, from where wood gas is released through a special telescopic pipe.

After this, the gas is directed into the heater nozzle, where diffusion (mixing) occurs with secondary air pumped by the fan. Thus, a continuous process will occur until the coals or firewood are completely burned. In this case, the combustion temperature sometimes reaches 1200 degrees.

The effectiveness of this principle lies precisely in the fact that solid fuel is consumed very slowly, as needed, which significantly increases the efficiency of such heating device. But not only high performance is the advantage of this design.

Important. Solid fuel (pyrolysis) long-burning boilers have very high efficiency compared to the classical design. It is equal to 95%.

As a rule, the whole point of long-lasting combustion is that not the entire load of coal or firewood burns out at the same time, but only the top layer. Due to the fact that air is supplied from above and not from below, fuel burnout occurs gradually, in its upper layer.

When this layer burns out, the air supply is turned on, and exactly as much as is needed to burn the top layer. This ensures such a burning duration and the ability to control the process.

It should be said that this version of the heating device is acceptable exclusively as a heating system. If you need to think about a water heating system for domestic needs, then you should look for other options.

If the option is selected specifically for heating big house, then such a device is an excellent alternative electrical and gas appliances.

Features of the design of a long-burning TT boiler

Typically, the design itself and the large dimensions of such a device already tell the consumer that it’s all about the large volume of the loading chamber. However, the duration of combustion here is determined not by a large amount of resources, but by slow smoldering.

Duration of combustion is ensured through the use of special techniques. Today there are 2 main long-burning systems used in such devices. These are the Canadian system Buleryan and the Baltic Stropuva.

The second system is less common in our country due to the high price and large number of technical parameters. But the Burelyan system is fundamental in the production of long-burning boilers presented on the modern market today.

It is a small oven that consists of two chambers. In the first (lower) chamber, solid fuel burns, resulting in the formation of gas. It enters the second chamber, which is located above the first. Here the hot gas mixes with air and further combustion occurs. High heat transfer and good air circulation are ensured by pipes located from bottom to top along the circumference of the boiler cylinder.

Of course, the duration of boiler combustion up to several days is determined by the need to load a large volume of fuel. For this purpose, the loading chamber door is located not at the bottom, but at the top of the boiler. The entire lower part is filled with fuel.

The smoke pipe is located at the top of the boiler, which is connected to the chimney. And at the very bottom you can see the ash pan, which is necessary for collecting ash and systematic access for cleaning.

If in conventional stoves the ash pan plays the role of a ash pan, supplying a portion of oxygen, then here the ash pan plays exclusively the function of collecting combustion residues, so its door is sealed. Where does the air come from? At the top of the boiler there is an air chamber, which simultaneously plays the role of a recuperator (here the flue gases heat its walls). That is, the air from the air chamber arrives already heated.

At the top of the chamber there is a damper that regulates the supply of air to the fuel. To ensure that oxygen is dosed into the chamber, there is an air distributor in the boiler, which is connected to the air chamber by a long telescopic pipe.

As the fuel burns, the distributor lowers along with the top layer of burning material, which ensures a constant supply of oxygen. In order to return the distributor to its original position, it is enough to pull the cable with the ring up. By the way, the remaining fuel in the chamber can be determined by the position of the cable.

As a result of this design, manufacturers are able to achieve productivity (efficiency) of up to 85%, and adjustable power from 50-100%.

Video. The operating principle of a long-burning TT boiler.

The principle of this design explains the high environmental friendliness of long-burning boilers. The percentage of carbon dioxide released into the atmosphere is very low.

The raw materials for combustion are usually coal, peat briquettes, firewood, and coke. But in addition to ordinary firewood, you can use any waste from the woodworking industry. This waste is crushed to a fine powder and then pressed into granules called pellets. Fuel can be combined - it all depends on the model.

The large volume of the loading chamber and the insufficient flow of oxygen into the combustion chamber significantly increases the overall efficiency of the TT boiler; taking these factors into account, the smoldering process occurs extremely slowly and can reach up to 7 days. Pyrolysis boilers are also good, but they are very demanding on the quality and moisture content of the source fuel. Yes, here productivity will also decrease with wet wood, but not as much as in a pyrolysis boiler.

Many models work on the basis of bulk wood substances (sawdust, wood chips), on peat briquettes or on the basis of wood pieces and sections.

Due to the fact that oxygen enters the chamber in limited doses, the smoldering process occurs very slowly. But at the same time, the resources loaded into the boiler are sufficient to produce generator gas with high thermal conductivity. Through a ceramic nozzle, it rushes into the main combustion chamber, where the active combustion process continues. In this case, the process is accelerated and supported by additional air created by the fan.

The flame itself is formed by mixing gas and air, and is intensified by the use of fans.

Due to the complexity of the design and volumetric dimensions, such units are mainly used for heating large premises and large country mansions. For small dacha or a one-story house, it is simply not economically justified to purchase such a boiler. The productivity of such units is too high.

The high performance of long-burning boilers is also achieved thanks to the favorable location of the heat exchanger, which is a water jacket. The design of the unit helps to evenly heat the water circuit around the entire perimeter. The temperature of the exhaust gases does not exceed 130-150 degrees. The heat released in the boiler warms up the coolant as efficiently as possible.

When choosing a long-burning boiler for your home, let's go over its main features. technical specifications and note the advantages and disadvantages.

Specifications

• Long-burning boilers, which can operate for up to 7 days, mainly operate on peat briquettes or wood shavings. There are also universal devices that allow you to work with different fuels, but its length should not exceed 40 cm. Otherwise, you will have to prepare firewood yourself.
• The higher the humidity of the feedstock, the lower the performance of the heating device will be. Therefore, for combustion, manufacturers recommend using fuel with a moisture content of no more than 20%.
• On average, 1 boiler load provides up to 7 days of continuous burning.

Advantages:

• High performance. Perhaps this is one of the main and significant advantages of such bulky units. The average efficiency is at least 90%.
• Environmental friendliness. Carbon monoxide entering the chimney is used as the main source of flammable gas formation.
• Relative availability and inexpensive price of solid fuel.
• Automation of the work process. Some models are equipped with a remote control that allows you to set the desired temperature.
• Saving time and resources.
• Autonomy of work. Can be used as the main heating device.
• High fire safety. Long-burning boilers are equipped with an alarm sensor that is triggered in any emergency situation.
• High reliability of the design. At correct operation equipment, the boiler will last for decades.

But no matter how efficient, economical and productive these boilers are, there are also some disadvantages of such devices.

Flaws:

• Large dimensions.
• High price.
• Regular cleaning required.

In order for a long-burning solid fuel boiler to serve for a long time and not cause burns or accidents in the house, you should: simple rules operation of this device.

Will the boiler really work for 7 days on 1 load of fuel?

Owners of dachas and private houses, when choosing a solid fuel boiler, are most interested in such parameters as price, power and combustion duration per load of fuel.

Here let's go to comparative characteristics and we will adhere to these basic criteria to determine which device will be most effective.

• Boiler power. This parameter depends on the volume of the loading chamber. The larger it is, the longer the boiler can burn with one load.
• The weight of the structure determines the material. A cast iron apparatus will be almost 20% heavier.
• Product price. This is a very conditional parameter. But if a boiler is purchased for the purpose of being the main source of heating, then you should not save, because the performance of the device and the comfortable microclimate in the house depend on this.

In any case, if the seller states that this boiler will work for 7 days on one load of fuel, be sure to take the trouble to look at the technical data sheet, because no matter how much he praises the features and advantages of the device, it is in the passport that its standard burning time will be stated.

Burning time does not always only depend on the chosen model. This parameter is influenced by the type and quality of fuel, room area, ceiling height, and quality of home insulation.

Correct installation of the boiler: step-by-step instructions

Many consumers, purchasing a solid fuel boiler and expecting from it the effect of long-term and economical burning of raw materials up to the stated up to 7 days, after some time pay attention to the fact that the device does not provide the declared efficiency. And the point here is not at all the poor quality or defective boiler, but the mistakes made during connection.

Of course, given the complexity of the design and the responsibility of this event, many entrust the installation of a long-burning TT boiler to specialists. However, following our detailed step-by-step instructions, you can install the boiler yourself, without outside help. Although you can’t do this without an assistant, because the device weighs at least 50 kg.

At the stage preparatory work, you should immediately think about where the boiler will be installed. Ideally, of course, to equip a separate boiler room.

Considering that solid fuel does create some dirt, such heating system must be produced in a separate non-residential premises. But if the boiler power is small (does not exceed 30-35 kW), then you can simply separate (zone) the main room from the “boiler room”.

To ensure that people servicing boilers and igniting them do not have breathing problems, the boiler room must be equipped with a ventilation system. Clean air must come from the street.

Prepare the following tools:

1. Locksmith set (adjustable, open-end, ring wrenches).
2. Building level.
3. Circular Saw.
4. Screwdriver and set of bits.
5. Marker.
6. Caulk gun.

In addition to the solid fuel heating boiler itself, you will also need to purchase materials to connect the boiler to the heating system.

• Steel coupling (3 pieces).
• Ball valve with drive (2 pcs) with a diameter of 50 mm.
• Metal pipe for connecting the boiler.
• Sealant (fireproof).
• Plumbing winding.

Stage 1. Preparing and protecting the premises.

The issue of fire safety should be approached with all responsibility.

When installing a low-power unit, it is allowed to install the boiler on a rough concrete screed.

Be sure to check the level of the foundation slope. It should be perfectly smooth. If necessary (if the floor is not level), a brick foundation should be laid.

1. Draw a marker or chalk on the floor where you will install the boiler and carefully double-check all distances. Maintain distance from walls (regulated by SNiP). The distance from the combustion door to the wall must be at least 125 cm. The distance between the side parts and the back of the boiler and the wall must be at least 700 mm.

Video. How to properly install a long-burning boiler in the house.

Stage 2. Boiler piping.

This stage is one of the most difficult. The security of the system will directly depend on it.

There are several boiler piping schemes: with forced and natural circulation coolant. In addition, there can be an open and closed heating system.

With a natural circulation system, water passes freely through all pipes under its own pressure. The forced scheme involves the installation of a pump that creates this pressure.

The choice of connection diagram largely depends on the number of floors of the house, the location of the boiler, rooms and the total area. Thus, it is advisable to use a scheme with natural circulation for one-story houses. But for rooms with several floors, it will be ineffective and it is better to purchase an additional pump to carry out a forced coolant circulation circuit.

But the simplest and most understandable is the closed (forced) scheme.

It is produced through 2 pipes. One is connected to the supply circuit of the heating network, and the second end to its return circuit.

Important! Whatever model of TT boiler you choose, it is not included with it. circulation pump and expansion tank. All this, depending on the selected connection system, must be purchased and installed independently.

To properly tie the boiler, follow these rules:

Installing a pressure gauge is a prerequisite when piping the boiler, since this device will monitor the maximum pressure value.

Stage 3. Connection to the chimney.

All solid fuel boilers must be connected to a chimney. If the house is already equipped efficient system gas exhaust, then you will just need to connect the new structure to it.

Attention! It is necessary to treat the joints connecting all parts of the chimney with sealant. This will help prevent smoke leakage

1. We connect the first chimney pipe to the boiler pipe. The type of connection depends on the selected boiler model. Required condition is to comply with the diameter of the chimney and the stove pipe. The diameter of the chimney pipe must be no less than the nozzle of the solid fuel boiler. If these parameters are not met, the throughput of the gas duct at maximum power will decrease.

Video. Connecting a solid fuel boiler to the chimney.

Attention! Under no circumstances should you install shut-off valves on the section of pipeline between the boiler and the safety group.

Stage 4. Connect the boiler to the heating system.

1. According to SNiP standards, before starting the boiler, it is necessary to conduct a hydraulic test under pressure with a holding time of 24 hours.

To do this, open the shut-off valves, all taps and connect the water. Raise the pressure with the control valve to 1.3 atm. This test should show you that there are no leaks. Pay special attention to threaded and welded connections.

1. We light the boiler.

To set fire to wood or peat, you need to put wood chips or paper in the chamber. Once the boiler is lit, close all doors tightly. After a stable flame has appeared, you can open the door and load the main amount of firewood. Never use flammable liquid for ignition.

1. During the first test run, an unpleasant chemical run may be present. This may be due to the fact that the remaining factory oil is burning through. Soon the foreign odors will go away.

If you have connected everything correctly, then the pressure should not drop during the test period and, accordingly, there should be no leaks anywhere. Now you can put the boiler into operation. If during the test period any problems were identified, then you should disconnect the boiler from the system, wait for it to cool completely and begin to eliminate errors.

At correct installation and connecting the boiler, you will quickly appreciate its high performance and efficiency, which will allow you to maintain a comfortable microclimate in the house. And the video instructions will help you take into account all the necessary nuances of installing the boiler.

Video. Correct connection of a long-burning solid fuel boiler.

A long-burning solid fuel boiler is an economical option for heating a home.

When choosing a solid fuel unit, you need to pay attention to:

1. Type of device, pros and cons of each of them.
2. Primary fuel type.
3. Power.
4. Loading chamber volume and combustion duration.
5. Material used to make the heat exchanger.
6. Energy consumption.
7. Autonomy and safety.

Kinds

Types of solid fuel long-burning units:

1. Devices operating on the top combustion principle.
2. Pellet.

Pyrolysis boilers

The peculiarity of these devices is that inside them there is pyrolysis, that is, the decomposition of firewood into simpler substances. These are charcoal (formed when) or coke (formed when loading coal) and gases, most of which are capable of burning and generating heat. Pyrolysis can only occur under conditions high temperature and lack of oxygen.

The main difference between pyrolysis furnaces is that almost all formed substances burn during pyrolysis (only carbon dioxide and nitrogen.) In other wood boilers, a lot of carbon monoxide comes out through the chimney. The combustion of the formed gases gives 90% percent of the heat produced by the stove. The heat generated by burning charcoal is largely used to support pyrolysis.

The gases formed during pyrolysis are heated and discharged into a separate chamber, in which they burn. Air is supplied to this chamber through a separate channel.

Pyrolysis furnace design:

1. Two cameras. Fuel is burning in one, and fuel is burning in the other. carbon monoxide. The second chamber can be above or below the firebox. The second option is more common. It is easier to produce.
2. Fan. Available in those wood boilers in which the afterburning chamber is located under the firebox. It is needed to supply carbon monoxide to the afterburner chamber. It runs on electricity. There is no fan in home devices with a combustion chamber located at the top.
3. System that supplies air into each chamber separately.
4. Heat exchanger.
5. Smoke exhaust. In models with a lower combustion chamber it is very simple. In the second type of home stove, it is shaped because the heat is very close to the chimney. If you don't collect it in time, it will come out. The coil prevents this problem.

Read also: Cleaning a solid fuel boiler from tar and soot

Pros and cons of pyrolysis boilers

Modern solid fuel boilers have the following advantages:

1. High percentage of fuel combustion.
2. Automatic operation. You just need to set up the operating mode, load firewood and clean it.
3. Ability to use any type of fuel. An exception for some models are pellets: they can fall into the lower chamber.

Flaws:

1. You can only use fuel whose moisture content is less than 20%.
2. and other electrical components require electrical current.
3. Need for a bypass valve or elevator unit when the coolant in the heating system is very cool. The return water must be heated, diluting it with hot water so as not to affect the pyrolysis process.

Boilers with the top combustion principle

Such devices can be called a hybrid of standard solid fuel boilers and pyrolysis ones because the coolant is heated both from the combustion of wood and from the partial combustion of carbon monoxide.

A home stove is a tall, narrow vertical container, in the middle of which is placed a large number of firewood or coal, and around which there is a water jacket. The fuel burns from top to bottom, and the released gases burn out at the top of the fire chamber. Because of this, you can put new firewood inside only after the fuel has completely burned.

The best solid fuel boiler of this type is Stropuva. If you burn wood in this device, you need to load it every 6-12 hours. It works on coal for up to 5 days.

1. Automatic adjustment of fuel combustion intensity.
2. Many options do not require electrical power.
3. Can work in a heating system without circulation pumps.
4. Relatively low price.

The main disadvantage is inability to provide good efficiency with poor fuel. It should have a humidity of 13-20%.

Pellet boiler

It got into long-burning units because it has a special design that allows load pellets once a month.

Read also: Features of stainless steel boilers

The design of this element of the heating system includes a container placed on the side into which pellets are poured. The capacity of the container is such that the pellets last for a whole month. Fuel from the bunker is supplied by a special mechanism. He works using electrical energy.

Advantages:

1. Efficiency reaches 90-95%.
2. Virtually complete combustion of fuel. Cleaning can be done once a month.
3. Fuel can be loaded once a month or several months (it all depends on the volume of the bunker).

Flaws:

1. Dependence on electric current.
2. High price.
3. Demand for whole and low-ash pellets.

Boiler power and fuel type

To select according to this criterion, you need to know how much heat it must create to heat the entire room and for heating water in an indirect boiler.

For heating a room, the power is determined based on the fact that per 10 square meters. m should account for 1 kW. This is provided that the walls are below 3 m. The amount of heat required to heat the water is added to the resulting figure. A certain reserve is taken into account.

You can burn in ovens:

1. Firewood.
2. Coal.
3. Peat.
4. Slate.
5. Pellets.
6. Briquettes and other types.

Loading chamber volume and boiler power

The ratio of these indicators is very important. It shows how often you will have to load firewood into the combustion chamber.

For example, the volume of the loading chamber of a pyrolysis boiler Viessmann Vitoligno 100-S 25 is 110 l. Power is 25 kW. The ratio will be 110/25 = 4.4 l/kW. This figure is good for boilers of this type, since on average it ranges from 3.44 to 4.9 l/kW.

Model "Stropuva" according to this indicator, it is better - 12.5-20 l/kW (the power of models ranges from 10 to 40 kW). The best in this ratio is a long-burning pellet boiler - 30 l/kW or more.

Heat exchanger material and type

This device unit can be made of cast iron or steel. Cast iron heat exchanger is a structure consisting of sections. It is completely collapsible. This feature provides many advantages:

1. Ease of transportation.
2. Convenient installation and maintenance.
3. Possibility of repair (bad section is replaced).
4. Need to clean less often. Even an element covered with soot or dry rust produces decent efficiency.

In some cases, a solid fuel boiler remains the only practical way to heat a private ohm. However, classic designs have one very unpleasant drawback: you constantly have to monitor the amount of fuel and add firewood or coal to the furnace room. A little delay or delay, and the coolant begins to cool.

You can develop a habit, create a strict schedule to ensure constant heating, or you can choose a long-burning solid fuel boiler that is extremely in a simple way capable of working on one bookmark for up to several days.

Operating principle and device

Traditionally, solid fuel boilers, like stoves and fireplaces, used active combustion of wood or coal. Due to controlled air supply, it was possible to achieve maximum heat transfer and good fuel combustion. However, active combustion too quickly uses up the entire volume of fuel stored in the firebox, making it necessary to constantly replenish its quantity.

In long-burning solid fuel boilers, the main idea is to slow down the fuel combustion process. If only one part of the bookmark is lit, then the total volume will be consumed over a much longer period of time.

As an example, it is enough to remember how long a match burns with the flame raised upward, and how quickly it flares up and burns with the flame lowered down, burning your fingers. This principle also applies to firewood and coal.

It is necessary to limit the combustion area in one place of the stowage and maintain it at the minimum required level, preventing the entire volume from igniting.

Long-burning boilers are equipped with a volumetric combustion chamber several times larger than that of conventional designs. Firewood or coal is filled to the top of the chamber, leaving only a small gap. Ignition is carried out from the top of the bookmark.

The chamber is isolated at the bottom; air flow is only from above if the boiler is top-burning. After ignition of the fuel, all oxygen from the chamber burns out and, in fact, the firewood located below the combustion area is preserved.

The air supply is controlled and strictly limited. As a result, the wood either smolders or burns only in the upper part of the chamber.

To supply air, a special blower fan is used, installed instead of a standard damper or in a separate seat. Just by controlling the fan, the combustion process of the boiler and the preparation of the coolant are fully controlled, which significantly simplifies the automation of the operation of solid fuel boilers.

Boilers are classified according to the method of localizing the combustion area:

• with top combustion;
• with bottom combustion (pyrolysis).

There is a fundamental difference between these two methods. Long-burning boilers, by definition, have top combustion, which ensures that the main volume of the charge does not warm up. Boilers with bottom combustion are pyrolysis. Although they are classified as a separate group, they are also long-burning devices.

When wood is heated above 300°C without active combustion, the wood begins to decompose into ash and pyrolysis gas, burning which can produce more thermal energy than with conventional active combustion, but with less power.

Active combustion produces a significantly greater heat output per unit time than upper or lower combustion of the same volume of fuel. To obtain the required power in long-burning boilers, it is necessary to increase the area of ​​low combustion and increase the amount of fuel put into the furnace.

This results in two main advantages long burning boilers:

• The gradual combustion of fuel is easier to control and the fuel lasts for a longer time, and the difference is an order of magnitude.
• It is possible to automatically control and regulate the thermal power of the boiler with gradual fuel consumption.

Operating principle of a pyrolysis boiler

Pyrolysis boilers are additionally equipped with a chamber for burning the released gas. The air supply is carried out separately from the main chamber with the filling, so active combustion can be maintained there with a large heat output per unit time.

Long-burning boilers with top combustion are often not equipped with grates, since there is no need to supply air from below, and it is easier to remove ash using a retractable solid pan, and this must be done almost every few weeks, or even a month.

Only combination boilers and pyrolysis boilers are equipped with grates, in which, in addition to long-term combustion, you can set the usual classical operating mode with complete and uniform burning of the filling.

Is it true that the download is once a week?

Indeed, some long-burning boilers can operate for up to a week on one filling of wood or coal. However, this mainly concerns heavy-duty units with output from 150 kV to several megawatts. An ordinary boiler for a private home is often designed for continuous operation on one load for up to 30-45 hours, that is, up to two days.

The main problem is the allowable size of the combustion chamber while maintaining adequate controllability of the entire process. It is necessary to choose a compromise solution between such parameters as:

• chamber volume;
• chamber depth;
• combustion area area;
• required boiler output power.

With an increase in the volume of the chamber for loading fuel, it is necessary to increase the combustion area, since making the chamber narrow and high will not work. In this case, it is difficult to maintain an active flow of air to the combustion zone when it drops too low.

A series of turbulent flows arise that can spread combustion to the entire volume and completely disrupt the normal operation of the boiler.

Boiler manufacturers are primarily based on the required thermal power of the boiler, and then on this basis, the dimensions of the combustion chamber are selected as a compromise solution.

Coal-fired boilers operate longer on one load than wood-fired boilers. For example, if a boiler is designed to operate on one load of coal for 17 hours, then on a load of firewood it will most likely only work for 14-15 hours, with the same heat output setting.

Double circuit or with water circuit for home

Long-burning solid fuel boilers can be equipped with one or two heat exchangers to prepare coolant for the heating and hot water systems. There are no fundamental differences from the design of conventional solid fuel kits. The circuits can be combined in one bithermic heat exchanger or located separately from each other.

The type and configuration of the heat exchanger is selected by the manufacturer based on the dimensions and shape of the furnace so as to maximize the use of thermal energy for its intended purpose.

Long-burning boilers operate with a smaller volume of air and a lower temperature of the combustion products. Heat exchangers are made with as large a heat exchange area as possible.

The advantage of long-burning boilers is the ability to control and regulate the combustion thermal power simply by adjusting the air supply, without regard to the amount of fuel loaded.

If in conventional boilers you have to limit the portions of firewood or coal and add more often to reduce the temperature of the coolant, then in long-burning boilers it is enough to limit the air supply so that the firewood only smolders.

Ukrainian production

Among Ukrainian manufacturers, the following companies produce long-burning solid fuel boilers: Altep, Buran, Gefest-profi, KOTeko, NEYS, SWaG, Donterm.

Boiler Altep KT-1E

Some of our own developments are presented, but due to the greater experience of European manufacturers, the models partially or completely repeat the successful solutions of Western partners, or licensed assembly is offered on the basis of regional factories and enterprises.

Brand and model	Power	Combustion type	Fuel	Duration of work	Cost, $
Altep KT-1E 15-45 KW	15	Top burning	firewood/coal	8-24 hours	950
Buran-12	12	Top burning	Firewood/coal/briquettes/waste	up to 30 hours	975
Buran -20 Delux	20	Top burning	Coal/firewood/briquettes	Coal - 12 days, Firewood-48 h Briquettes - 72 h	1200
SWaG 20 kW Dm	20	Top burning	Coal/wood/pellets	Coal - up to 5 days.	1050
NEYS NEUS-V	10-38	Top burning	Coal/wood/pellets	8-24 hours	750-1200
Donterm DTM KOT-10T	10	Top burning	Coal/firewood/briquettes	Up to 48 hours	450

Russian made

Russian-made solid fuel boilers are mainly represented by a number of brands, while the equipment itself is sometimes assembled at the same production facilities.

Common brands include: Phantom, Teplov, Burzhuy-k, F.B.R.Zh., Zota, Wester, Don, Sibenergotherm (Prometheus), Tepoldar (Cooper PRO), Buderus.

In almost all cases, long-burning boilers or pyrolysis boilers are a processing of the classic layout with an increase in the combustion chamber and restructuring of the air supply system.

However, models such as Prometheus or Zota boast a unique design of the heat exchanger and combustion product removal system, focused specifically on pyrolysis lower or upper combustion of fuel.

Brand and model	power, kWt	Combustion type	Fuel	Duration of work, h	Cost, thousand rubles
Burzhuy-K T-50A	50	Pyrolysis/firewood	firewood	6-12	138/149 single-circuit / double-circuit
Burzhuy-K T-150A	150	Pyrolysis/firewood	firewood	6-12	315/336 single-circuit / double-circuit
ZOTA “Carbon”	15-60	Bottom burning/coal	coal	10-12	40-84
Teplov T10	10	Pyrolysis/wood/coal	firewood	up to 12	40/44 single-circuit/double-circuit
Teplov T100	100	Pyrolysis/wood/coal	firewood	up to 12	190/210 single-circuit/double-circuit
Phantom Max 30a	30	Pyrolysis	firewood	up to 20	100
Phantom Max 90 a	90	pyrolysis	firewood	up to 20	236

Boilers Stropuva

The Stropuva company, established in Lithuania since 2000, is engaged in the production of long-burning boilers and ready-made solutions For autonomous systems heating with automatic control. Boilers have specific appearance due to significantly increased volume combustion chamber , and mostly upward.

The shape of any model is a tall cylinder, inside of which there is a volumetric chamber, an air supply system and heat exchangers for the heating and hot water circuit. The design and operating principle of Stropuva boilers is patented, so it is hardly possible to find an analogue, but on the market you can already find a lot of fakes that are much inferior in terms of characteristics and quality to the originals.

STROPUVA IDEAL boilers are a universal solution for working with firewood, coal, and fuel briquettes. The main feature is the presence of perfect automation, which allows you to set operating modes of heating equipment with high accuracy. However, this line includes only models with a power of 20 and 40 kW.

Stropuva boiler design

STROPUVA boilers are universal - boilers for burning almost any type of solid fuel from wood waste to coke and coal. Partially automated, mainly in relation to maintaining a long-term combustion mode. The lineup represented by boilers with power from 10 to 40 kW.

STROPUVA wood boilers are a simple solution in cases where the main type of fuel is, by definition, wood. The list of models starts with a power of 7 kW, as perfect solution for small country house or dachas.

How to choose

The main criterion when choosing a long-burning boiler is its rated thermal power, moreover, when using the main type of fuel.

After this, you should pay attention to:

• combustion chamber volume;
• operating time from one load;
• version and availability of automation;
• possibility of using other types of solid fuel;
• number and characteristics of heat exchangers.

You should not count on a fuel load that will be enough for a week in boilers positioned for a private home. Optimal value battery life ranges from 17 to 45 hours, which is quite suitable for private use.

The operating principle of solid fuel boilers is based on the combustion of wood and coal. Additionally, you can use peat briquettes. Only specialists can install long-burning solid fuel boilers. Today there is a wide range of this product on the market. In order to make a choice heating device, all its advantages and disadvantages should be taken into account.

Advantages of devices

First of all, it should be noted the low cost of fuel. Nowadays you can easily order firewood at a low price and with delivery. Thus, boiler maintenance costs are kept to a minimum. Another advantage lies in the control unit with which the device is equipped. It can be used to regulate the temperature. Ecologically, solid fuel boilers are not harmful to humans. Their efficiency is quite high.

Among other things, good performance should be noted. With one fueling of wood, the boiler can operate for a long time.

Minuses

Unfortunately, solid fuel boilers also have disadvantages. Most significant minus is their service. It is carried out only once a month, but it takes a lot of time. In this case, absolutely all ash must be removed from the chamber. The chimney also needs periodic inspection.

The second drawback lies in the fuel. You need a lot of it, and this will require a significant area. For small houses this poses a serious problem. The boiler takes up a lot of space. Its installation is quite complicated. If the installation rules are violated, the owner may have serious problems with the operation of the device.

Secrets of a successful purchase

To select a quality boiler, you should carefully study the place in which it will be used. First of all, it is necessary to determine the overall quadrature. Additionally, the place where the boiler is installed is subject to inspection. There should be no flammable items there. Fuel should be stored at a certain distance from the device.

Device housings are made from different materials. Cast iron structures have proven themselves well.

The rated power must be at least 15 kW. At the same time, fuel consumption is within 3 kg per hour. The efficiency is on average 80%. The combustion chamber is usually about 240 mm deep. In this case, the diameter of the chimney should be 150 mm. Its normal thrust is around 14 Pa. The noise level is assessed individually. Average values ​​are within 65 dB. In this case, the volume of water space must be at least 30 liters. The cost of boilers depends solely on the manufacturer.

Boilers of the Viadrus company

The Czech manufacturer offers high-quality solid fuel heating boilers with decent characteristics. There are a wide variety of models, so you should choose them based on the area of ​​the house. The efficiency is at an average level. They work best on coke and coal; firewood is rarely used by consumers.

One of the features is a high-quality heat exchanger. It is made of cast iron. The boiler grates are cooled using ordinary water. For more comfortable installation of equipment, manufacturers have provided special flanges. They are attached to the device using threads. The above heating boilers for a private home will be just right. The company's pricing policy is quite soft, so you can choose an inexpensive model.

Characteristics of Viadrus S3 boilers. basic information

These solid fuel pyrolysis boilers are made of cast iron. Moreover, they consist of three sections. The rated power of the device is within 17 kW. In this case, fuel consumption is 3 kg per hour. The efficiency is 80%. Maximum temperature coal combustion - 480 degrees. The central chamber of the boiler has a depth of 240 mm. The diameter of the chimney is 156 mm. The thrust indicator is at the level of 14 Pa. Working water pressure - 400 kPa. The recommended temperature for heating is 80 degrees. The volume of water space is significant. Thanks to this, the noise level is only 60 dB. These heating boilers (market price) will cost approximately 45,000 rubles.

Review of the Viadrus D7 model

The Viadrus D7 boiler differs significantly from the device described above in its characteristics. The rated power of the model is 38 kW. Moreover, there are as many as seven sections in the boiler. It works most effectively on lump wood. However, it is also possible to refuel with coal. Fuel consumption will be approximately 11 kg per hour. The efficiency in this model is 75%. The maximum combustion temperature reaches 320 degrees. The central chamber has a depth of 620 mm. The recommended log length is 540 mm. The chimney diameter is 156 mm. In this case, the thrust parameter is at around 22 Pa.

Additionally, mention should be made of connecting a return water device. The operating pressure is within 400 kPa. The recommended temperature in the boiler is 90 degrees. The volume of water space is 43 liters. The noise level in this model is 65 dB. The moisture content of wood for use should be no more than 20%. Judging by user reviews, such solid fuel boilers are excellent for a private home. "Viadrus D7" will cost the buyer approximately 60,000 rubles.

Boilers of the Altep brand

Altep solid fuel pyrolysis boilers have an average power of about 20 kW. In this case, the area of ​​the heat exchangers may vary. The efficiency is 80%. On average, about 8 kg of fuel is burned per hour of operation. The large dimensions of the boilers should also be taken into account. The device weighs on average 300 kg. The maximum water temperature reaches 90 degrees. The cross-sectional area of ​​the chimney is 225 square meters. cm. In this case, the internal diameter is 170 mm. The minimum chimney height is 5 m. Altep boilers cost from 40,000 rubles. Reviews about them are mostly positive.

Model "Altep KT-1": review and price

Such heating boilers are suitable for a private home. The rated power of this model is 15 kW. In this case, the heat exchanger has an area of ​​1.8 square meters. m. Efficiency factor - 80%. Thanks to low fuel consumption, you can save money. The depth of the firebox is 350 mm. Moreover, its volume is 65 cubic meters. dm.

Additionally, the large boiler capacity should be taken into account. It is 74 liters. The weight of this model is 280 kg. The recommended minimum water temperature is 58 degrees. Maximum - 90 degrees. The average operating pressure is maintained at 0.15 MPa. The diameter of the network connection is 50 mm. The chimney for this model must be at least 5 meters. Its internal diameter is no more than 170 mm. In this case, the cross-sectional area should be approximately 225 sq.cm. This solid fuel cast iron boiler will cost approximately 55,000 rubles. Reviews characterize it as a reliable device.

Characteristics of the device "Altep KT-2"

Compared to the previous model, this boiler is more powerful. Additionally, a high-quality heat exchanger is installed. All this will allow you to heat the house faster. Fuel costs will, of course, increase. An hour of work on average will require about 15 kg of firewood. The efficiency is 80%. The firebox in this model has a standard depth of 350 mm. Its total volume is 81 cubic meters. dm. The water capacity of the boiler is 80 liters.

The assembled weight of this model is 310 kg. The minimum water temperature is 58 degrees. The maximum is 90 degrees. The nominal pressure is maintained at 0.15 MPa. The diameter of the network pipe is 50 mm. The cross-sectional area of ​​the chimney is 256 square meters. cm, and its minimum height is 5 meters. The price for this solid fuel cast iron boiler ranges around 60,000 rubles.

Bosch products

Bosch solid fuel heating boilers stand out among other similar devices for their ease of use. For this, manufacturers have provided a large loading window. Heat exchangers are made of cast iron. The dimensions of the boilers are quite compact, they have a good efficiency. On average, the power parameter is 20 kW. Fuel consumption is 4 kg per hour of operation.

The operating temperature ranges from 40 to 90 degrees. The number of sections depends solely on the model. The combustion chamber has an average volume of 30 liters. The width of the loading hatch is 310 mm, and the height is 230 mm. The average weight of the boilers is 230 kg. Among the shortcomings, judging by the reviews, one can note only the high cost of the equipment. Prices for Bosch boilers start from 60,000 rubles.

Characteristics of the Bosch Solid 2000 model

The rated power of the device is 10 kW. This boiler is not able to heat a large area. Among the advantages, one can note a rather voluminous firebox. In this case, you can load firewood no longer than 150 mm. The efficiency is 82%. Fuel consumption is insignificant. The minimum operating temperature is maintained at 45 degrees. Maximum - 90 degrees. This model consists of four sections. In this case, the combustion chamber has a volume of 25 liters.

The maximum pressure that the system can withstand is 4 bar. The loading hatch at the boiler is of standard size. The height of the model is 1344 mm, width - 840 mm, and depth - 490 mm. In this case, the total weight of the device is 210 kg. On the market, this model will cost the buyer approximately 60,000 rubles. Users respond well to it.

Review of the Bosch Solid 3000 boiler

The height of the device is 1344 mm, the depth is 490 mm, and the width is 940 mm. Weight - 245 kg. The maximum power indicator is 20 kW. Thanks to this, the room can be heated very quickly. This is especially true for houses with a total area of ​​up to 100 square meters. m. The efficiency of this model is 82%. At the same time, fuel consumption is quite noticeable. There are five sections in the boiler. At the same time, the volume of the boiler chamber increased. The loading hatch has standard sizes(width - 310 mm, height - 230 mm). These solid fuel heating boilers cost 65,000 rubles.

New model - "Proterm Copybara"

These long-burning solid fuel boilers are considered universal. They are great for heating a home with wood as well as coal. The heat exchanger of the device consists of cast iron. The control is mechanical, operation in autonomous mode is not provided. Thermal power model is 17 kW.

The temperature control range ranges from 30 to 90 degrees. The maximum pressure that can be maintained is 3 bar. The chimney diameter is 160 mm. The volume of the combustion chamber is 32 liters. The weight of the model is 190 kg. Such solid fuel heating boilers cost approximately 60,000 rubles. As users note, these devices are a suitable option for a summer residence.