Long-burning solid fuel boilers Stropuva

Solid fuel boilers have become a part of everyday life in private households. When constructing a new building or replacing outdated equipment, the owner is faced with the question of choosing a boiler installation.

In addition to the criteria of reliability and cost, the time spent plays an important role. For those who do not have the opportunity to refuel and clean out ash several times a day, the Stropuva long-burning solid fuel boiler is suitable.

Features of solid fuel boilers Stropuva

The main difference between Stropuva units is long burning. It is achieved by combining the principle of upper layer-by-layer combustion and the design features of the product.

Device

The boiler design is a shaft of two steel cylinders located one inside the other. The coolant, water, circulates between them.

Inside the smaller cylinder are the combustion chamber and the air heating zone. A heated air flow is supplied from above into the firebox using a telescopic pipe with an air distributor at the end. The air duct rests on the fuel and descends with it as it burns out.

The body is lined with thermal insulation. On its front panel there are two doors: the loading chamber and the ash pan.

Principle of operation

The device implements the combustion principle from top to bottom. It allows fuel to burn more slowly, providing more efficient use of thermal energy. The bookmark is set on fire from above. Only the surface layer of the fuel material burns. As it burns out, the hearth gradually sinks into the lower layers. This ensures uniformity and duration of operation of the unit on one portion of fuel.

More details about the operation of the Stropuva boiler can be seen in this video.

Advantages

Buying such a heating device would be reasonable, because it has many advantages, which we will consider in more detail.

Advantages of Stropuva boilers:

1. Economical. The method of layer-by-layer combustion from above, unlike the traditional one, does not create “excess heat” thrown into the chimney. Thermal energy is released evenly and manages to be almost completely transferred to heating the coolant, and not the street. The boiler does not waste fuel resources.
2. Energy independence. To operate the heating device in the basic version, no connection to the electrical network is required. It is completely autonomous.
3. Safety. The absence of electrical and gas components reduces the risk of accidents. If used incorrectly, the unit may fail and become deformed without causing harm to surrounding objects and people.
4. Long combustion cycle. On one stack of firewood, the firebox operates for up to 30 hours. On coal and pellets - even longer. The device will have to be serviced less often than once a day. Ideal for those who value their time.
5. Low waste. It is enough to clean the ash chamber a couple of times a month. Thanks to complete combustion, there are practically no combustion residues and resins left.
6. Efficiency. Efficiency of 85% is much higher compared to traditional water heating devices.
7. Design and dimensions. The device has a modern appearance and does not take up much space in the room.
8. Wide palette of 7 body colors. A harmonious solution can be chosen for any interior.

Flaws

It is necessary to keep in mind some of the disadvantages of such boilers.

Disadvantages of Stropuva devices:

1. Cyclicality. The boiler goes through the stages of kindling, combustion and end of operation, regardless of the duration of the cycle. Periodically, you have to refill a fresh portion of fuel, remove the ash, and re-ignite the firebox.
2. Inconvenient loading window. It is inconvenient to load and distribute firewood through the small door.
3. Price. To buy a Stropuva boiler, you will have to spend an amount comparable to the cost of a gas boiler.
4. High requirements for fuel quality. It is allowed to burn material with a moisture content of no more than 20%. Otherwise, tar and soot will form on the inner walls.

How the device works

Stropuva boiler with a fuel storage tank
The operating principle of Stropuva heating equipment is based on burning fuel in its upper part. This effect is achieved by supplying oxygen to the top layer of wood waste, coal or briquettes. As it burns out, the hearth moves to the lower part of the firebox until all the material is exhausted.

The efficiency and high efficiency of the equipment is due to slow combustion and smoldering, in which almost all the thermal energy is used to heat the water in the circuit. Due to the fact that the flame in the firebox is not intense, in most cases overheating and boiling of the coolant is impossible, so in a heating system of this type you do not need to use an expansion tank.

If firewood is used as fuel, on average the supply in the combustion bunker needs to be replenished once every 30 hours. With a more powerful energy source - coal - it is enough to fill the firebox once every five days.

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.

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.

Review of model range and prices

The range of heating devices in Stropuvo is represented by products of various capacities and configurations. Let's look at the popular models of Stropuva solid fuel boilers and their prices.

Mini S8

Stropuva Mini S8 is a solid fuel single-circuit wood-burning device with a low power of 8 kW. Suitable for heating small rooms from 50 to 80 square meters. m. The installation has modest overall dimensions: height - 1.35 m; diameter - 0.56 m. The firebox can hold up to 37 kg of firewood up to 40 cm long. The maximum operating time on the stack is 18 hours. The dimensions of the loading door are 23x21.5 cm. The model has a basic configuration, including cleaning accessories: a poker and a scoop.

The cost of the model is 53,000 rubles.

Prices for the Stropuva Mini S8 boiler

Stropuva Mini S8

Mini SP8

Unlike the previous model, it is equipped with a grate and an air injection fan. Heating with pellets increases the burning time of one portion to 48 hours.

Price for Stropuva Mini S8P: 56,500 rubles.

Prices for the Stropuva Mini SP8 boiler

Stropuva Mini SP8

S20

Wood-burning version with a power of 20 kW (firewood and briquettes). Capable of heating a room of 100-200 square meters. m. The firebox holds 60 kg of firewood. This is enough to work for 31 hours. The height of the device is 2.1 m. The diameter is standard.

Cost - 85,500 rubles.

S40

The most powerful option is 40 kW. Works on wood. Suitable for residential and industrial buildings with an area of ​​200 to 400 square meters. m. The loading zone can accommodate up to 93 kg of logs up to 45 cm long. The combustion cycle is up to 31 hours. The design is distinguished by an oversized loading door of 24x23 cm and a diameter of 0.68 m.

The price of Stropuva S40 is 98,600 rubles.

Prices for the Stropuva S40 boiler

Stropuva S40

Other models

The Stropuva model range is represented by versions of 8/15/20/30 and 40 kW with a heating area from 50 to 400 sq. m. m. Basic wood-burning models are marked with the letter “S”. The letter “P” in the name stands for pellet heat generator. Unlike the basic version, it works longer on one tab - up to 72 hours. It is heated with both wood and fuel pellets. The letter “U” denotes universal boilers. Such devices can burn for up to 5 days on coal.

Advantages and disadvantages

The equipment is recommended mainly for heating summer cottages and country houses for temporary use. The equipment is designed for 50-500 sq.m. area. The models are distinguished by automated control, which is configured remotely. From a remote distance, the owner can not only monitor, but also set the temperature.

Important! The Stropuva boiler is compatible with pressure and non-pressure heating systems. The equipment is also suitable for gravity pipe routing.

The manufacturer provides warranty service for five years. Moreover, both components and parts, as well as the design of the boiler as a whole, are subject to warranty repair.

The main disadvantage is the high cost. On average, models are sold for 80-130 thousand rubles.* In this case, it is necessary to additionally install a special chimney.

The models are characterized by increased sensitivity to the quality of the coolant. Its temperature matters; for example, when it drops to 55 degrees, the efficiency of the equipment drops to zero. In addition, the internal surface of the equipment is covered with condensate, which forms a crust that reduces the transfer of thermal energy by 5-15%.

Note! For “Stropuva” long-term burning, only dry firewood with a humidity of about 15% is suitable. Raw fuel produces thick smoke, which causes soot to settle on the walls. Firewood produces a lot of ash, and untimely cleaning of it reduces the combustion temperature of the fuel.

At the same time, ordinary coal is categorically not recommended for Stropuv. When burned, the top layer of fuel turns into a sintered crust. It will not let the fire go lower, as a result, no afterburner chamber will be formed, and the efficiency of the device will drop significantly.

What fuel is suitable

There are several suitable types of fuel.

Stropuva units heat:

1. Hardwood. The logs are placed evenly throughout the volume of the firebox. Long ones are in the middle, short ones are at the edges. The stack should be completed with large firewood and approximately 0.5 kg of wood chips or shavings for ignition. Wood fuel leaves a lot of ash that needs to be removed regularly.
2. Wood briquettes. Briquetted material burns longer and more evenly than firewood. It is laid horizontally. For kindling, take small dry wood chips.
3. Peat and briquettes made from it. When burned, the material emits a characteristic sour odor. When working on peat raw materials, the boiler emits more harmful substances into the atmosphere than when using wood. This type of fuel should not be used in urban environments.
4. Large anthracite. It is used only in conjunction with wood, otherwise it will not burn well. It is recommended to remove unused pieces from the ash and add them to the firebox the next time you add them.
5. Coal. For ignition, combine with wood. Low-quality coal is laid in layers, alternating with logs.

Recommendations for each type of fuel are presented in the table.

Step-by-step instructions for starting the boiler

Before loading fuel, lift the distributor by pulling the cable by the ring on the front panel and secure it with a hook. Open the damper slightly.

The fuel resource is used most efficiently when fully loaded. Bookmarking is done through the top door.

Laying features:

1. Firewood is placed on the boiler floor in layers horizontally as close to each other as possible. It is advisable to close the gaps between the logs with sawdust, wood chips or shavings.
2. A grate is used with coal. Firewood is placed underneath so that the grate does not burn out. On top there is a thin layer of wood - for ignition.
3. The peat is stacked in the following sequence: large briquettes directly onto the grate, then smaller ones.

To start a fire, small firewood, wood waste and paper are placed on top. Set it on fire and let the hearth burn. The camera is covered, leaving a gap of several centimeters. When the temperature rises to 40-50°C, close the door and remove the cable from the hook.

Important points:

• the lower chamber must not be opened when the boiler is operating, otherwise air entering from below will disrupt its operation;
• it is forbidden to reload fuel until the previous portion has burned out, so as not to violate the principle of top combustion;
• To avoid burns, loading should be done when the temperature drops to 40°C.

Video instructions for kindling are shown in the following video.

Reviews from real users - useful to read

Advertising characteristics and indicators do not always guarantee clients that everything will work exactly like this.
Sometimes during operation many additional factors are revealed that are not stated in the instructions and advertising. But advertising, as we know, is a one-sided review of positive characteristics, while user reviews are a comprehensive review .

Troublesome boiler for 3-4 days of autonomous combustion mode

In general, reviews of the STROPUVA boiler agree on one thing - it burns for a long time and this is its main attractive quality. But in addition to the positive aspects, you need to take into account its “appetite”, difficult loading and unloading and the inability to do additional loading.

Three winters with this boiler brought a variety of feelings into my life. The first thing I would like to note is the fact that the specified burning time in the instructions (up to 7 days on coal) did not come true. My powerful boiler with a full load of coal, which is about 200 kilos, was enough for 3-4 days and no more. I tried to increase the heating time by disconnecting half of the house from heat, as well as insulating the walls, however, this did not work. In addition, this Stropuva gourmet runs exclusively on selected fuel: very dry wood and selected coal. Where can I get all this? A full load of firewood only burns for 24 hours.

An additional “bonus” is that there is no way to add additional load to the boiler during the combustion process! You have to wait a day until it cools down completely, when it no longer really heats up.

Reviews of the Stropuva 40 kW boiler

I am involved in construction and have experience installing these boilers in several houses. The efficiency of the boiler is definitely exaggerated - one load of 80 kg briquettes gives only one knock of combustion at a temperature of -10 outside .

You need to additionally buy an electric heating unit.

Internet forum, builder

It works on a mixture of firewood and coal for up to 2 days in autonomous mode, and if the coal is selected, then it pulls out all 3. What’s bad is the formation of slag, which is normal in boilers where combustion is from top to bottom. Judging by the materials, they are not designed for burning coal; such a thing will burn out quickly. I would like to bookmark it once a week, but there are no ideal boilers. Unless you build such a unit yourself.

Forum, discussion of boilers

My 40 kW Stropuva works in tandem with an electric boiler. It heats up quickly, and when fully loaded it lasts for 2 days. But given the price of coal, a one-time load of 200 kg is a luxury. The boiler is also very capricious about the quality of the coal - it is too fine or coal with dust does not burn well. It doesn't work much with wood, only 10 hours.

What can I say, in the absence of an alternative, I am still happy with the boiler. There are plans to figure out how to increase the burning time of one load of fuel.

Internet resource, discussion of Stropuvo boilers

I don’t like the troublesome installation of firewood in this boiler. It takes time because they need to be placed tightly together. You have to select it so that the bookmark burns as long as possible. And the downside is that through the stowage window you cannot reach with your hand the top row of logs that are placed through the bottom window. This is really a problem!

Internet resource

Working version for those who read the instructions

Many users note that the STROPUVA boiler is good, however, you need to be careful about its installation and use. Some users have kindly compiled mini-instructions for beginners in working with a solid fuel boiler.
This Stropuva will work well under one condition - you can properly perform the piping and set up the boiler. Of course, they will deliver it to you and do the pipe piping, but how is the second question. Perhaps the system is installed incorrectly, or the firewood is damp, but I am collecting too much soot. Every month I have to clean this deposit.

Apart from the disadvantage described, I am absolutely satisfied with everything about my boiler.

Internet forum, discussion of the Stropuva boiler

Disadvantages can be found in any boiler, one has a lot, another smokes, and so on. I bought the S20 model for firewood . This boiler has a natural intolerance for stupid plumbers, but if the thinking works, it will work.

What can we say about the impossibility of reloading - yes, but the house does not cool down immediately, unless you have a cardboard box. In fact, this is even saving.

The only thing that confuses me is the company's pricing policy, but the owner is a gentleman.

Internet resource

for a long time, and finally bought my Srtopuva 20 U. While I installed it, I thought I would go crazy, I had to dig through a bunch of literature myself. And it was not in vain that the plumbers had to show how to make the piping. In our open spaces there are no competent boiler installation specialists, so I advise you to take the situation into your own hands. The boiler, by the way, is good, but you need to understand that this is not a potbelly stove. Although it is written that he is an omnivore, he eats oak firewood well. For me, they dry naturally under a canopy, and I can say that properly stacked firewood keeps burning for up to 30 hours. I cut heating costs in half, so I don’t agree about its gluttony.

I even created a small instruction manual for dummies (it took me a long time to find out all this):

1. You can only lay logs horizontally and make sure that they do not intersect.
2. The boiler must be completely extinguished; if this is not the case, then close the doors and the top damper (ring to the right). If there is a lack of oxygen, it will go out completely.
3. The water pump must be disconnected from the power supply, i.e. just turn it off.
4. The top layer of logs is pine, it should be level with the loading door.
5. The chips need to be laid on top of the pine, with the smallest ones under the larger ones.
6. Pour the ignition mixture over the wood chips, no more than 40 ml. If you poured more, do not rush, let it evaporate a little, otherwise you will get a small “bang”.
7. It is better to lower the air supply pipe, carefully bleeding the outer cable.
8. Open the top flap by turning to the left.
9. We set fire with such a long torch, moving further away.
10. While this whole thing is heating up, we do not close the loading door completely, leaving a gap. This way the boiler will gain power much faster.
11. We turn on the pump when the temperature is already at 60 °C.
12. The door can be closed completely when the combustion stabilizes. We immediately set the upper flap with a ring to the red mark.
13. It is best to clean the ash pan more often.

Victor, review of Srtopuva 20 U for 220 m²

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.

System piping

Piping the boiler is no different from other solid fuel units.
When piping the device, in addition to conventional heating radiators, you need to include a safety battery in the system, on which you do not need to install a thermostat. This convector must be embedded first on the jacket supply pipe through a balancing valve and mounted in such a way that the coolant can move in it by gravity in the event of a power outage.

All other radiators go through a different circuit through regular valves and are connected by return to the circulation pump. The pump itself is bypassed through a three-way valve, which is connected through a second channel to the return pipe of the unit and is controlled by a temperature sensor installed on the return pipe of the batteries.

Among the most popular models of solid fuel boilers Stropuva are the wood-burning unit Stropuva 10S and the universal device Stropuva 20U, with 10 and 20 kilowatts of power, respectively, intended for heating country cottages.