Long-burning Stropuva boiler: device, review of models

Peculiarities

The Stropuva boiler has one striking feature - it has top combustion of fuel. This means that the flame moves from top to bottom, which allows the fuel to burn for a longer time. In this way, you can save significantly, because you will need much less coal or firewood to heat the room. The principle of top combustion also determines the vertical cylindrical shape of the device.

The device is a barrel made of cast iron or steel, inside of which there are two cylinders (small and large), differing in diameter. The large one is separated from the boiler itself using a layer of thermal insulation. A heat exchanger, also known as a heating circuit, is located between the cylinders. The coolant is evenly distributed in this zone and a so-called “water jacket” is formed. The combustion chamber is mounted in a small cylinder, that is, the firebox is located there.

The combustion temperature is maintained due to the presence of an air duct. It works in such a way that air flows only to the burning fuel. With its help you can regulate the entire process. The smoke leaves the boiler in its upper part and is directed immediately into the chimney due to the presence of strong draft. The diameter of the latter varies from 160 to 200 millimeters depending on the model. In any case, it must match or even exceed the diameter of the pipe on the boiler. Ash and other waste are removed from below - the door is placed 2 centimeters higher than the bottom itself.

To light the boiler, you have to follow simple instructions. First, the air distributor is raised and fuel, such as firewood and wood chips, is loaded. The dampers open, including the air damper, and the top layer is set on fire. At this moment, the door through which the fuel is loaded should remain ajar a few centimeters. When the fire reaches the desired state, the air distributor is lowered and the loading door is closed. A new portion of wood material can be added at any time, but it is not recommended to do this with coal - you need to wait until the previous portion burns out.

For Stropuva, ​​various types of solid fuel are selected: types of wood (sawdust, wood chips, briquettes and firewood), coal or peat briquettes. The quality of the chosen fuel largely determines how long it will burn and warm the room. In addition, the presence of insulation in the house and the correct selection and installation of the device play an important role. If the room is not insulated enough, then you will have to buy a powerful boiler and be prepared for the fact that the bookmarks will last for less time.

Qualified employees who will install the boiler and its piping are also important.

Design and principle of operation

The structure of the Stropuva boiler from the inside looks like two cylinders installed according to the “pipe-in-pipe” principle, that is, the small one is located in a larger diameter, which in turn is separated from the walls of the boiler body by special thermal insulation.

The heating circuit (heat exchanger) is located between these cylinders. The combustion chamber is located in a small cylinder. Fuel is loaded through a special door on the front of the housing; ash is removed through the bottom door. The boiler is designed in such a way that only part of the fuel located on the surface burns.

Due to the built-in distributor, warm air from a special chamber enters this outer layer of logs and coal through a pipe to heat it. Together with the combustion of the top layer of firewood, this distributor is lowered together with the fuel combustion center into the lower part of the solid fuel unit. It must be said that the air distributor is always located inside the combustion chamber.

Boiler design Stropuva

In order to regulate the air supply to the boiler and the temperature of the liquid in the heat exchanger, a bi-thermal draft regulator is installed, located on top of the boiler body. With its help, the efficiency can reach more than 86%.

Combustion products envelop the combustion chamber from the outside and are discharged through a special hole into the chimney, along the way helping to achieve greater heat removal inside the boiler body.

The diameter of the chimney for Stropuva solid fuel units must be no less than the diameter of the smoke outlet pipe on the boiler itself. This indicator is individual for each model: from 160 to 200 mm.

Advantages and disadvantages

Reviews from owners indicate that heating boilers from this company have many advantages. Stropuva is better than its counterparts in many ways. The main advantage, of course, is continuous combustion and the ability to use one bookmark for a long time. For example, if you choose coal as fuel, then one load will last for almost a week, and briquettes will last for two days. If you have to heat the room with wood, then the stash will last for thirty hours. Standard models can function on one tab for no more than eight hours. According to users, the device is very easy to use and there are no loading issues with it.

Stropuva boilers are also quite economical. They themselves are relatively inexpensive, as well as the fuel used, which can be ordinary wood, coal, wood chips or other common materials. If we compare Stropuva products, which are solid fuel devices, with a conventional pellet boiler, the benefits will be obvious. There will be no unnecessary fuel consumption - only as much as needed. You can change the mode depending on changing conditions and thereby extend the burning hours of one bookmark. For example, if it gets warmer outside, less energy will be required, which means the boiler will run on fuel longer. When switching to Stropuva, ​​heating costs are reduced by approximately half.

The boiler from Stropuva always works in the best mode. A conventional boiler operates until all the fuel is burned, and in a short period of time produces a huge amount of heat. Therefore, you have to either constantly update the bookmark, or supplement the design with a heat accumulator that will store heat. In Stropuva, ​​only a small part of the fuel is burned and no additional devices are required. The efficiency of the boilers reaches 90%, and the boiler itself is non-volatile and can work with almost any solid fuel. Even if there is no electricity in remote areas, Stropuva will still be successfully operated. It is also worth mentioning that the boiler itself is quite compact and does not take up much space, it is very easy to clean, and it can function for up to 5 years.

Boilers of this type are distinguished by their safety for users. The device is made of steel, characterized by increased heat resistance and heat resistance. If there is a fire, the boiler will not explode anyway. In addition, the design is equipped with a special protection valve, which in case of danger activates the extinguishing mode. Stropuva can be easily equipped with radiators and boilers, connected to underfloor heating, as well as any heating system. You can set different temperatures for different connections. For example, the heated floor will maintain a temperature of 33 degrees, and the radiators will maintain a temperature of 55 degrees.

Boiler fuel

Stropuva solid fuel boilers can operate on:

• ordinary logs;
• briquettes made of wood and peat;
• sawdust;
• coal;
• pellet granules.

When using only firewood as fuel, the boiler will operate for up to 1.5 days on a one-time basis. The use of wood pellets can ensure combustion of one bookmark for up to three days, the use of coal – up to five days. All this is possible thanks to a special patented combustion technology.

Stropuva boiler combustion technology

Design and principle of operation of Stropuva boilers

Loading fuel into the Stropuva furnace is possible only from above. For better ignition, the main fuel is mixed with sawdust; you can add flammable liquid. Ignition also occurs through the top door, which must be closed tightly after all actions.

The chimney will form a draft, the fire will flare up from the top of the fuel. Quickly igniting the firewood will ensure good air flow. Fire and smoke rush through the inner housing structure to the smoke hole. Some of the hot gases also rush upward, simultaneously heating the metal and water.

The internal chamber of the air duct increases as the fuel burns. An afterburning chamber is formed in the increased space, which has a positive effect on efficiency. In this case, the fire will not flare up too much, the protection will work in the device. Thanks to the device, the air damper either opens or closes, increasing or decreasing the draft or combustion temperature.

Boiler design

Structural diagram of a wood/pellet boiler*

* The diagram is shown conditionally; the actual location, as well as the type of parts and components of the boiler may differ from the image.

Design diagram of a universal boiler*

* The diagram is shown conditionally; the actual location, as well as the type of parts and components of the boiler may differ from the image.

Description of the boiler design

The boiler is a steel cylinder surrounded by a second steel cylinder of larger diameter, the structure is insulated. In the gap between the cylinders there is a heated coolant. At the front of the boiler there is a bi-thermal draft regulator {2}. The design has a door for storing firewood {8}, a door for removing ash {11} and a hole for exhaust gases {5}. There are also coolant supply and return pipes {14, 15} and a coupling for installing a thermometer {16}. To improve the quality of combustion and heat transfer, an air heating chamber {4} is installed in the upper part of the combustion chamber. The boiler may include a grate and a bottom air supply regulator {19} for firing with peat and sawdust briquettes or coal. To achieve optimal heat removal, there is a gap between the air heating chamber and the walls of the boiler combustion chamber along the entire perimeter, through which smoke, washing the air heating chamber, enters the exhaust gas hole. In the gap between the air heating chamber and the walls of the combustion chamber, cleaning plates {economizers} are installed, which are used to regulate the exhaust gases. When the plates are brought as close as possible to the chimney outlet, the heat extraction from the exhaust gases is maximum. In this case, the temperature of the exhaust gases decreases to 110-180 °C. When the plates are brought as close as possible to the boiler door {to the front of the boiler}, the heat extraction from the exhaust gases is less, while the temperature of the exhaust gases is higher {180-220 °C}. A telescopic air supply pipe {7} is lowered into the combustion chamber, at the end of which an air distributor {9} is attached. At the top of the air heating chamber there is an opening for air intake and an air damper {1}. On the right side of the boiler there is a cable for lifting the air supply mechanism with a ring {12} and a fixing hook {13}. The purpose of the air distributor is to properly distribute air in the combustion zones. The air distributor moves down as the fuel burns under the force of gravity.

It is not recommended to lift the air distributor during combustion to avoid premature wear.

Types of equipment Stropuva

Stropuva heating devices operate on one or more types of fuel, depending on the model.

Wood-burning

A wood boiler uses hardwood logs, wood and peat briquettes as fuel.

Pellet

The pellet device obtains thermal energy by burning fuel pellets consisting of wood and agricultural waste. It is equipped with an air charge fan, a grate and a specially designed air distributor.

Universal

Universal models, in addition to firewood and pellets, also use coal and anthracite. It is equipped with special parts for working with bulk raw materials.

Types of boilers Stropuva

1. Long-burning solid fuel boilers operating on wood and wood waste. They are completely independent of the power supply and will heat the room even if there is no electricity. These include models: S-7, S-10, S-20, S-40.
2. Universal long-burning solid fuel boilers operate on several types of fuel: firewood and wood waste, sawdust or peat briquettes, coal, regardless of their quality and humidity level. Such a unit requires connection to the electrical network, this is necessary for the regular supply of oxygen to the firebox; it consumes about 20 W per hour, which is very economical. Models of universal boilers: S-10U, S-20U, S-40U.

The boilers of this company are completely safe to use; if the load is exceeded, which is permissible, or if there is severe overheating, the boiler will not explode; its design is made in such a way that it will shrink inward. The boilers are equipped with a large-volume firebox, which allows you to add a large amount of fuel at once, which will gradually burn through thin layers. As it burns out, the air distributor lowers, as a result of which the heated gases rise into the chimney, giving off heat to the inner walls of the boiler.

Main models

You can buy a Stropuva boiler in specialized stores that are dealers of the manufacturer, as well as in online stores. The minimum price is 60 thousand rubles for the minimum power model. Let's continue the review with a description of the models being produced.

Stropuva Mini S8

Before us is the smallest wood-burning boiler with a power of 8 kW, designed to heat rooms up to 80 square meters. m. It works on wood briquettes and firewood, is equipped with a safety valve and a thermometer. The heating temperature of the coolant is from +60 to +95 degrees. The maximum pressure in the circuit is up to 1.5 Bar. The efficiency of the model is 85% - a pretty good result for solid fuel equipment. The estimated cost of this boiler is 61 thousand rubles.

Stropuva Mini SP8

This boiler differs from the previous model by supporting operation with pellets. In this mode, it needs to be connected to an electrical network with a voltage of 220 Volts - the electricity is used to operate the fan used in the fuel ignition system. When working with wood and briquettes, the boiler operates in autonomous mode. The remaining parameters are almost 100% similar.

Stropuva S20

One of the most popular models. It allows you to heat residential buildings up to 200 square meters. m. The boiler is built according to an energy-independent scheme; briquettes and ordinary firewood are used as fuel. Burning time is up to 31 hours. If you want to forget about adding fuel for several days, we recommend purchasing the Stropuva S20U modification - it can run on coal, providing up to 120 hours of continuous combustion. The Stropuva S20P model can work on pellets for up to three hours.

Stropuva S40

Before us is the most powerful boiler in the entire line. Its thermal power is 40 kW, combustion duration is up to 31 hours, heated area is up to 400 sq. m. The device is equipped with a rather impressive heat exchanger jacket that holds 58 liters of water. The maximum pressure in the system is up to 2 atmospheres at an average temperature of up to +75 degrees. Over 90 kg of firewood is placed in the combustion chamber of the device. Modifications for working on pellets and coal are also available.

Other models and manufactured modifications

Also on sale are solid fuel boilers from the Stropuva company with a capacity of 15 and 30 kW. They are designed for areas up to 150 and 300 square meters. m. All models discussed in the review are available in three modifications:

• The main one is that the equipment runs only on wood and fuel briquettes (euro firewood).
• With index P – the possibility of working on pellets is provided, burning up to 72 hours.
• With index U - units with the ability to operate on coal, burning time up to 120 hours.

Naturally, the actual burning time may be shorter - it depends on the characteristics of the fuel (type of wood, degree of dryness).

Some people have design requirements for their heating equipment. If you really care so much about how the boiler looks, then we have good news - Stropuva produces its equipment in several colors. The main color (and most common) is yellow. It is possible to purchase boilers in brown, blue, red, green and black colors. Spotted colors are also available (yellow and dirty green).

Boiler duty cycle

The entire volume of fuel is poured into the boiler and ignited from above (see lighting instructions).

As the top layer of fuel burns, the boiler power increases to that required to maintain the set temperature of the system.

The fuel in the boiler burns slowly, the burning layer of fuel slowly sinks down. The air supply pipe also lowers under its own weight, supporting combustion.

As soon as the fuel has burned out, the cycle can be repeated again.

Firewood

Maximum combustion up to 18 hours.

STROPUVA S8

• Firewood / Briquettes
• Heating area: 50-80 m²
• Power: 8 kW
• Burning up to: 18 h
• Fuel capacity: 163.15 dm³
• Firewood capacity: 37 kg

90,000 rub. / PC

Firewood

Maximum combustion up to 31 hours.

STROPUVA VILLAGE V30 kW

• Firewood / Briquettes
• Heating area: 200-300 m²
• Power: 30 kW
• Burning time: 31 h
• Fuel capacity: 341.88 dm³
• Firewood capacity: 78.43 kg

108,000 rub. / PC

Firewood

Pellets

Coal

Maximum combustion up to 120 hours.

STROPUVA S20 U

• Coal / Firewood / Briquettes / Pellets
• Heating area: 100-200 m²
• Power: 20 kW
• Burning up to: 120 h
• Fuel capacity: 234.31 dm³
• Firewood capacity: 60 kg

118,000 rub. / PC

Reliability and safety

Stropuva pellet boilers are not equipped with complex, malfunctioning automation. The boiler is controlled by a fairly simple in design and non-volatile bimetallic draft regulator. This solution gives the boiler high reliability and stability in operation.

The boiler is designed in such a way that, unlike diesel, electric or gas boilers, if the load is repeatedly exceeded, it will not explode, but will shrink inward. The manufacturer is confident in the quality of the equipment produced and provides a factory warranty of up to 5 years.

Recommendations for installation and operation

To install the device, choose an isolated room equipped with forced ventilation or an opening window. The height of the boiler room ceilings must be at least 2.5 m, the area - from 4 sq. m. Installation work is carried out strictly according to the instructions.

Installation features:

• the boiler is installed on a concrete foundation 10 cm high from the floor or on a non-combustible base;
• the bottom is lined with concrete mortar, the joint is sealed with heat-resistant sealant;
• maintain the following intervals: in front - at least 1 m of free space, in the back - 0.6 m, on the side to the wall - 0.6 m;
• The connection points between the device and the chimney and heating system are carefully sealed.

The heat generator is a source of increased danger. The boiler room must be equipped with fire extinguishing equipment and a container with sand for emergency fire extinguishing.

Other operating features:

• Do not store fuel or other flammable materials near the heating device;
• once a month it is necessary to check the condition of the chimney using a mirror, and if necessary, clean it from soot accumulation;
• operation in systems with forced circulation is not allowed if the pump fails or there is a power outage;
• When heating with wood, ash is removed as needed;
• when using peat or coal, the ash pan must be cleaned every time before refilling;
• It is advisable to lubricate the distributor lifting cable with oil to prevent wear;
• It is necessary to inspect the doors for tight closure.

Reservation of work

The use of two or more boilers in a heating system is justified by the risk of failure of one of the devices. The circuit is also used to quickly increase power if necessary.

Stropuva units are easily assembled in a cascade, thereby increasing the reliability of the heating system.

Advantages of cascade installation:

• uninterrupted operation (if one device fails, the other will continue to operate);
• increased power (in the off-season you can use one unit, in winter - two);
• ease of repair and maintenance;
• saving space in height (for limited spaces - attics, basements).

The disadvantage of parallel connection is that for each device you have to connect a separate piping unit and chimney. Study the Grundfos circulation pump at the link.

Guide to self-assembly of a Stropuva boiler

Before starting work, prepare the necessary equipment for this.

You won’t need any extremely difficult to use tools or hard-to-find materials. However, it is better to collect everything in advance so as not to be distracted by searching for missing elements in the future.

Stropuva boiler assembly kit

1. Metal barrel. Use a large container with a capacity of 200 liters or more.
2. Welding machine.
3. Thick-walled metal pipe.
4. Fiberglass.
5. Metal channels.
6. Asbestos.
7. Chisel.

The function of the body of the heating unit in question will be performed by a large metal barrel. You can use either new or old container. The main thing is that the barrel does not have through holes and signs of severe corrosion damage.

The function of the body of the heating unit in question will be performed by a large metal barrel

If possible, it is best to use a Soviet-made barrel. Such products are much more durable and high quality compared to their modern counterparts.

If you have access to a rolling machine, you can purchase a large sheet of metal and use it to assemble the boiler body. The recommended sheet thickness is 2.5-3 mm. The optimal dimensions are 125*250 cm. At the end you should get 2 cylinders with a diameter of 50 and 45 cm.

Furnace assembly

The work of making a sling boiler is carried out in a few simple steps.

First step. Clean the barrel from all sorts of contaminants, and then cut a hole in its top. That is, you simply need to “knock out” the top of the container to gain free access to its interior.

Sheet metal housing

Second step. Cut a small piece from a metal pipe with a diameter of about 15 cm. From it you will make a pipe for connecting the chimney.

Bubafonya stove with water jacket

Pyrolysis furnace Bubafonya from a gas cylinder with a water jacket.

Finally, we got to the domestic analogue of the Stropuva boiler, which is much simpler to implement, since it has a non-folding pipe for supplying air to the firebox. There are already so many instructions on how to make a Bubafonya stove with your own hands that only a blind person would not have seen them, unless, of course, they were interested in this topic. And why all? Yes, because the process is so simple and if you take the matter seriously, you can get a finished product from scratch in a day. What is the Bubafonya stove made from with your own hands:

• from a gas cylinder;
• from a barrel;
• from pipes

It can be either round or square. Let’s not repeat the same thing, just read the article: “Bubafonya stove from a gas cylinder” - and everything will become clear to you. Today we will consider a version of the product with a water circuit, as if we will try to repeat the principle of operation of the Stropuva boiler. All that is required is to make a simple Bubafonya and insert it into a pipe of a larger diameter. Thus, we obtain a gap in which the coolant will be heated.

Naturally, this space above and below is sealed so that various debris does not get there. What is important when making a Bubafonya stove with a water jacket with your own hands:

• use of heat-resistant steel;
• wall thickness of at least 4 mm;
• the presence of a tap for draining and replenishing water.

Immediately provide a hole in the upper part through the outer and inner walls for installing a chimney into it. There should also be enough space for water. The distance from the outer to the inner wall is about 10 cm. When connecting, do not confuse the supply and return pipes (supply from above).

Long-burning solid fuel boilers Stropuva

• We offer to buy Stropuva solid fuel boilers with delivery in the Tavago online store.
• The price of Stropuva solid fuel boilers is from 53,000 rubles.
• Read instructions and reviews about Stropuva solid fuel boilers.

The Stropuva long-burning solid fuel boiler differs from a traditional type boiler operating on solid fuel by a special combustion process. Ignition of the loaded fuel occurs in the upper part of the boiler and the combustion front slowly moves from the top of the load downwards. This design allows fuel to be burned in a slower mode without reducing heat transfer parameters. The time of continuous operation from one load of coal can be up to 5 days. Nowadays, when we are all spoiled by automation, which is present in literally every device and mechanism, it is quite strange to get a Stropuva wood-burning boiler where it is completely absent. But, as the 1st law of technology says: the simpler it is, the more reliable it is. And it is unlikely that it will be possible to automate the process of loading the firebox - there is no way around manual labor. In addition, unnecessary automation and electronics will only increase the price of the product. Another interesting feature of these boilers is the absence of a bottom in most models. It was decided to produce “bottomless” boilers after consultations with heating engineers who carried out an expert assessment of the design for compliance with EU safety standards. Such boilers are installed on a concrete pad. This year, the production of boilers with bottoms for installation on tiled floors began. Stropuva solid fuel heating boilers are produced by 2 factories - the main one in Vilnius and a subsidiary in Kyiv. The lineup includes two types of equipment:

• wood-burning boilers Stropuva S7, S10, S20, S40 – fuel used: sawdust briquettes, wood chips with a moisture content of up to 25%, firewood
• universal boilers Stropuva S10, S20U, S40U – fuel used: wood chips, firewood, coal, pellets – the ability to use fuel with a moisture content of more than 25%, wood, sawdust and peat briquettes, pellets

The Stropuva single-circuit solid fuel boiler can only be used for heating. If autonomous hot water supply is required, then a water boiler must be connected. To select the correct model, you need to take into account the correspondence of the power of Stropuva long-burning solid fuel boilers to the area of ​​the heated room:

• 7 kW – 20 – 80 m2
• 10 kW – 50 – 100 m2
• 20 kW – 100 – 200 m2
• 40 kW – 180 – 400 m2

The heating area, as well as the power of the heating system, is not limited by the parameters of the boilers, since cascade assembly of several devices into one network is possible. An additional advantage that a cascade connection provides is the organization of a semi-automatic operating mode with sequential reloading of boilers. The advantages of Stropuva solid fuel boilers, which distinguish them from products with a traditional combustion method:

• long period of fuel combustion from one load
• energy independence
• ergonomic design
• economical fuel consumption
• low operating costs (cheaper than gas)
• high efficiency – 91%
• high degree of reliability
• safety in operation
• lack of energy storage capacity
• 5-year warranty on heat exchanger

Disadvantages of Stropuva heating boilers using solid fuel:

• the need to equip an efficient chimney
• Requires competent wiring and adjustment by qualified specialists
• “manual control” - loading fuel, cleaning the firebox
• quite high cost

If it is possible to use solid fuel for heating and you are not afraid of the need to sometimes roll up your sleeves to add firewood or coal to the firebox, then the Stropuva solid fuel boiler will be an excellent choice, and also very inexpensive to operate. The Tavago store will help you with choosing the model that is optimal for performance, as well as with strapping and installation work.

Comparison of the Stropuva boiler and the Bubafonya stove

We will begin our analysis with the scope of application. If we are talking about a residential building, the Stropuva boiler definitely has the advantage. The characteristics of this unit allow it to work for a long time on one load, it is stable and reliable. At least, cases of complete failure have not yet been encountered. The operating principle of the Stropuva boiler allows you to connect to it both high-temperature heating and a hot water supply system with heated floors. Bubafonya cannot boast of this.

It is more suitable for heating greenhouses, garages, or, at most, summer houses. For more serious projects it is simply not applicable. Advantages of the Stropuva boiler design:

• continuous operation on coal for 5 days;
• temperature stability;
• ease of fuel loading compared to Bubafone.

There are also disadvantages, such as the complexity of the piping, the need for a separate room and the impossibility of repairs until a complete stop. It is also impossible to add fuel while the stove is operating and therefore you have to relight it every time you reload the firebox. But at the same time, of the two units being compared, only the Stropuva factory furnace is still suitable for serious projects. But Afanasy Budyakin’s invention is excellent for utility rooms, since the Bubafonya stove can be made quickly and inexpensively, which in this case is of decisive importance.

Checking the boiler after assembly

Checking the boiler after assembly

Before accepting a homemade Stropuv boiler for permanent use, be sure to ensure that it is in good working order and reliable. Don't ignore this step. The safety of further operation of the heating unit directly depends on a correctly performed check.

Fill the barrel with wood to about a third of the height. Add some kerosene and throw a lit match into the container. Ideally, the wood will ignite almost immediately. At the same time, you should not notice the presence of smoke, or any draft, or any kind of uncharacteristic odors.

STROPUVA

If any of the above symptoms are present, do not use the boiler. Such equipment is very likely to soon fail and harm its owners. But if you assembled the unit in strict accordance with the instructions above, there will be no problems.

The amount of firewood given earlier will be enough for approximately daily heating of a small room. If the room is medium sized, double the loading volume.

Thus, you can assemble an excellent sling boiler for heating a variety of small and medium-sized rooms with your own hands. Now you don’t have to spend a lot of money on buying expensive equipment. You just need to follow the instructions in everything and your home will always be warm and cozy.

Good luck!