Designs of heating boilers. Making a wood-fired boiler with your own hands. Horizontal solid fuel boiler from a barrel

The heating system of a private house is a complex piping scheme, the heart of which is a heating boiler. The coolant is heated in it, which, under the influence of the laws of physics or with the help of a circulation pump, moves through the pipes, enters the radiators, where it gives off its heat, and cools down again into the boiler. And this process is repeated ad infinitum.

The modern market of boiler and heating equipment today offers a huge range of heating devices. Unfortunately, the price of many models is not affordable for everyone. Therefore, some consumers are faced with the question of whether it is possible to make a heating boiler with their own hands, whether this homemade device work as efficiently as factory counterparts? You can make a boiler if you are a good welder and it will work no worse.

Types of heating boilers

First of all, you need to decide which boiler is needed for your home. This will depend on the fuel that will be used for kindling. Hence the classification:

gas;
electrical;
solid fuel;
liquid fuel.

Electrical

Any of these boilers can be made by hand. The simplest of them is electric. In fact, this is a tank in which the heating element is mounted. From the tank there are still two branch pipes connected to the supply and return circuits. There is no chimney, no combustion chamber, everything is simple.

All are good, but they have two drawbacks. First, electricity is the most expensive fuel. Second: when the voltage drops in the network (and this happens with enviable constancy), the boiler stops working correctly. Its power decreases, the coolant temperature drops.

Gas

The rest of the designs are more complex. And they are almost identical to each other with some differences. As for the gas boiler, you will need permission from the gas service to install it.

Representatives of this organization may not accept such a heating unit for installation. First of all, they will require it to be pressure tested in their laboratory.

The presence of an act is a guarantee that permission will still be given to you.

The operation of this option is associated with great difficulties. First, you will have to build a separate warehouse near the house where the fuel will be stored. Everything in it must meet the requirements fire safety.

Secondly, a pipeline will have to be pulled from the warehouse to the boiler room. It must be insulated. Thirdly, a special burner is installed in this type of boiler, which must be adjusted. This is not so easy to do in terms of setup.

Solid fuel

It is this type of boilers that today is most often made by home craftsmen with their own hands. For small dachas and cottages, this best option. Moreover, firewood is by far the cheapest type of fuel.

We will talk about how to make a solid fuel boiler for heating a house below.

What will be needed?

As mentioned above, in order to weld a heating unit, you must be a good welder. Work at the level of an amateur is not suitable here.

Tools

What is required for this work. Of the tools you will need:

electric welding machine;
gas cutter;
Bulgarian;
hammer;
roulette;
marker or chalk.

materials

From materials:

seamless pipe with a diameter of 425 mm;
pipe with a diameter of 100 mm;
pipe with a diameter of 25 mm;
metal sheet 4 mm thick;
two drives with a diameter of 25 mm;
small loops;
corner 25 mm;
fittings with a diameter of 8 mm.

Project

Many beginners look for boiler drawings on the Internet or in specialized technical literature and are already working on them. Basically, this is the right way.

Most importantly, find drawings that indicate the dimensions of the heater.

Case manufacturing

So, first of all, the details of the future unit are prepared. The body of the heater will be made from a 425 mm pipe. For a small heating boiler, a height of 1.0-1.2 m, taking into account the small diameter, is the best option.

We cut the pipe to these dimensions using a gas cutter. We process the edges with a grinder.

Now it is necessary to cut two holes in the body: for the firebox and for the blower. They must be rectangular. For a firebox, a size of 20x10 cm is suitable, for a blower 20x3 cm. They are located one above the other, the furnace hole is higher.

The distance from the edge of the pipe to the blower is within 5-7 cm. The distance between the holes is 5 cm. The edges of the hole are processed with a grinder. The cut out piece of the pipe wall for the firebox will be used as a door. Its edges are also cleaned.

Using a cutter, two more holes are cut for the supply and return pipes with a diameter of 25 mm. The holes are opposite each other. At the same time, the return hole is cut out on the side of the boiler above the furnace: from the furnace hole at a distance of 15 cm.

At a distance of 5 cm, only from the upper edge of the housing, a hole is cut for supplying the coolant. Immediately, two drives can be welded to these holes.

Three pancakes are cut out of a metal sheet: two with a diameter of 425 mm, one with a diameter of 412 mm. The latter will be installed inside the body, and since the wall thickness of the pipe is 6 mm, 12 mm falls on the diameter, plus 1 mm for free entry.

In one of the pancakes with a diameter of 425 mm and in a circle of 412 mm, a hole with a diameter of slightly more than 100 mm is cut in the center. A chimney is being prepared from a 100 mm pipe. For this, a segment of 120-130 mm is cut. Pieces 50 mm long are cut from a 25 mm pipe for the legs of the boiler. A grate for an ash pan is made from the reinforcement, the size of the inner diameter of the body is taken as a basis.

Assembling the heating unit

First of all, a chimney is welded to a 412 mm pancake. Then, inside the body at a height of 30-35 cm from the furnace hole, temporary stops must be welded. It can be wire or fittings. A pancake with a chimney falls on top of them.

Main joints

And now the most important point- it is necessary to weld the pancake and the boiler body together. It is necessary to boil the seam on both sides and it must be done with high quality. This joint is the junction of the firebox and the water tank.

The next step concerns the combustion chamber. On the reverse side of the chimney, a finished reinforcement grate is inserted into the body.

Then, from a corner of 25 mm, several pieces are cut out by a grinder, which are welded inside the boiler between the furnace hole and the blower. These will be the stops on which the grate will lie.

Lower body

And the last. It is necessary to weld a 425 mm pancake to the lower edge of the body, weld four legs from a 25 mm pipe 5 cm high to it. Next, hinges are welded on which the firebox door is hung.

Blower valve design

The design can be different: in the form of a conventional door, in the form of a gate (this is a damper that moves in the plane of the hole), in the form of a rotary damper with holes in the body. Finished products are sold that are simply welded in place.

You can weld a one-piece structure with your own hands and attach it to the boiler. Of all the proposed options, the simplest is either a door or a gate.

Testing and connection to the system

Solid fuel boiler for home heating is ready. Now you need to check it. To do this, a plug is screwed onto one of the drives, and water is poured into the second. If water does not pass through the welds, then the welding was carried out at a high level.

You should not be afraid that the heating unit will leak during operation. The finished unit is connected to the heating system country house. That is, the drives are connected to the supply and return pipes of the coolant.

The chimney is being installed. Please note that this element of the device must exit vertically upwards. If it is not possible to arrange it in this way, then there should be a minimum number of taps.

In an unheated attic, it will have to be insulated.

First kindling

It is very important to correctly conduct the first furnace. In this case, you can not use a large amount of fuel. A small bookmark should heat the unit itself, especially the chimney. With a sharp increase in temperature, condensation may form on its walls, which will turn into tar, narrowing the diameter. And this is a decrease in thrust, which is responsible for the correct operation of the heater.

Gap adjustment

During the combustion process, the gap in the blower is adjusted. Need to find optimal size which will provide combustion chamber necessary quantity fresh air (oxygen).

Be sure to pay attention to the height of the bookmark. Its upper edge should be located at a distance of 20 cm from the inner pancake. This distance will ensure optimal combustion of wood or coal. At the same time, the smoke and carbon monoxide will be freely discharged through the chimney.

Principle of operation

In fact, a traditional solid fuel boiler works like a conventional stove. There is also a firebox in which firewood (coal, pellets and other types of solid fuels) burns. The released energy heats the coolant located in the tank above the combustion chamber.

The heat carrier in this design is heated both from the internal pancake and from the chimney, which pierces through the container with water. At the same time, the boiler body also heats up, which creates an accumulative effect that prevents rapid cooling when the unit is turned off.

The heated coolant rises and exits through the upper pipe into the supply circuit of the heating system. The cooled coolant enters the boiler through the lower pipe connected to the return circuit.

Other options

For home heating, it can be made in the form of a cube from a metal sheet 4 mm thick. This is a more complex design, in which you will have to assemble a separate combustion chamber. It turns out that a combustion chamber is installed in the boiler body. And between the walls of the two structures, the coolant will circulate. This is a more efficient option, but difficult to manufacture. It has a lot of welds, which reduces the reliability and safety of operation.

“A boiler is really a stove in a barrel of water” ... and the efficiency of such a unit will be at best 10%, or even 3-5%. Some kind of, but a solid fuel boiler is not a stove at all, and a solid fuel stove is not a hot water boiler. The fact is that the process of combustion of solid fuel, in contrast to gas or combustible liquids, will certainly stretch in space and time. Gas or oil can be completely burned immediately in a small gap from the nozzle to the diffuser of the burner, but wood-charcoal cannot. Therefore, the requirements for the design of a solid fuel heating boiler are different than for heating furnace, it’s impossible to just put a water heater of the heating circuit into it in continuous circulation. Why is this, and how should a continuous heating boiler be arranged, and this article is intended to explain.

Your own heating boiler in a private house or apartment becomes a necessity. Gas and liquid fuels are steadily rising in price, and in return, inexpensive alternative fuels appear on the market, for example. from crop waste - straw, husks, husks. This is only from the point of view of the owners of the house, not to mention the fact that the transition to individual heating will make it possible to get rid of energy losses in the CHP mains and power lines, and they are by no means small, up to 30%

You can’t do a gas boiler yourself, if only because no one will give permission for its operation. It is forbidden to use individual liquid fuel boilers for heating residential premises due to their high fire and explosion hazard in decentralized use. But a solid fuel boiler can be made with your own hands and formalized, just like a heating stove. This is perhaps the only thing they have in common.

Features of solid fuel

Solid fuel does not burn very quickly, and not all components that carry thermal energy burn out in its visible flame. For the complete combustion of flue gases, a high, but quite definite temperature is necessary, otherwise conditions will arise for the occurrence of endothermic reactions (for example, nitrogen oxidation), the products of which will carry the energy of the fuel into the pipe.

Why doesn't the boiler bake?

The furnace is a cyclic device. So much fuel is loaded into its furnace at once so that its energy is enough until the next heating. The excess combustion energy of the fuel load is partly used to maintain the optimum temperature for afterburning in the gas path of the furnace (its convective system), and is partially absorbed by the body of the furnace. As the load burns out, the ratio of these parts of the fuel energy changes, and a powerful heat flow circulates inside the furnace, several times more powerful than the current heating needs.

The body of the furnace is, therefore, a heat accumulator: the main heating of the room occurs due to its cooling after heating. Therefore, it is impossible to take away the heat circulating in the furnace, because of this, in one way or another, its internal heat balance will be disturbed, and the efficiency will drop sharply. It is possible, and even then not in every place of the convection system, to take up to 5% to replenish the DHW storage tank. Also, the furnace does not need operational adjustment of its thermal power, it is enough to load fuel based on the required hourly average for the time between heatings.

A water boiler, no matter what fuel, is a continuous device. The coolant in the system circulates all the time, otherwise it will not heat up, and the boiler must at any given moment give exactly as much heat as it has gone outside due to heat loss. That is, the fuel must be either periodically loaded into the boiler, or the thermal power must be promptly regulated within a fairly wide range.

The second point is flue gases. They must approach the heat exchanger, firstly, as hot as possible in order to ensure high efficiency. Secondly, they must be completely burnt out, otherwise the energy of the fuel will settle on the register with soot, which will also need to be cleaned.

Finally, if the furnace heats around itself, then the boiler as a heat source and its consumers are separated. The boiler requires a separate room (boiler room or furnace): due to the high concentration of heat in the boiler fire hazard much higher than ovens.

Note: an individual boiler room of a residential building must have a volume of at least 8 cubic meters. m, ceiling not less than 2.2 m high, opening window not less than 0.7 sq. m, constant (without valves) fresh air supply, separate from other communications smoke channel and fireproof interchange from the rest of the rooms.

From this it follows, firstly, boiler furnace requirements:

It must ensure rapid and complete combustion of the fuel without a complex convection system. This can only be achieved in a furnace made of materials with the lowest possible thermal conductivity, because. Fast combustion of gases requires a high concentration of heat.
The furnace itself and the parts of the structure associated with it in terms of heat should have the lowest possible heat capacity: all the heat that went into heating them will remain in the boiler room.

These requirements are initially contradictory: materials that conduct heat poorly, as a rule, accumulate it well. Therefore, an ordinary furnace furnace for a boiler will not work, some kind of special one is needed.

Heat exchange register

The heat exchanger is the most important unit of the heating boiler, it basically determines its efficiency. According to the design of the heat exchanger, the entire boiler is called. In domestic heating boilers, heat exchangers are used - water jackets and tubular, horizontal or vertical.

A boiler with a water jacket is the same “stove in a barrel”, a heat exchange register in the form of a tank surrounds the furnace in it. A jacketed boiler can also be quite economical on one condition: if the combustion in the furnace is flameless. A fiery solid fuel furnace certainly requires afterburning of the exhaust gases, and in contact with the jacket, their temperature immediately drops below the value required for this. As a result - efficiency up to 15% and increased soot deposition, and even acid condensate.

Horizontal registers, generally speaking, are always inclined: their hot end (supply) must be raised above the cold one (return), otherwise the coolant will reverse, and the failure of forced circulation will immediately lead to a severe accident. In vertical registers, the pipes are arranged vertically or in a slight slope to the side. Both here and there pipes, so that gases “get tangled” better in them, are arranged in rows in a checkerboard pattern.

Regarding the directions of movement of hot gases and coolant, pipe registers are divided into:

Flowing - gases pass generally perpendicular to the flow of the coolant. Most often, such a scheme is used in horizontal industrial boilers of high power for the sake of their lower height, which reduces the cost of installation. In everyday life, the situation is reversed: in order for the register to properly capture the heat, it has to be made stretched upwards above the ceiling.
Countercurrent - gases and coolant move along the same line towards each other. Such a scheme gives the most efficient heat transfer and the highest efficiency.
Flow - gases and coolant move in parallel in one direction. It is rarely used in boilers for special purposes, because. In this case, the efficiency is poor, and the equipment wear is high.

Further, the heat exchangers are fire-tube and water-tube. In fire tubes, smoke tubes with flue gases pass through a water tank. Fire tube registers work stably, and vertical ones give good efficiency even in a flow circuit, because. internal water circulation is installed in the tank.

However, if we calculate the optimal temperature gradient for transferring heat from gas to water based on the ratio of their density and heat capacity, then it turns out to be about 250 degrees. And in order to push this heat flux through the wall of a steel pipe of 4 mm (it is impossible to do less, it will burn out very quickly) without noticeable losses in the thermal conductivity of the metal, about 200 degrees are needed. Eventually, inner surface the smoke tube must be heated to 500-600 degrees; 50-150 degrees - operating margin for fuel water cut, etc.

Because of this, the service life of the fire tubes is limited, especially in large boilers. In addition, the efficiency of a fire-tube boiler is low, it is determined by the ratio of the temperatures of the hot gases entering the register and those leaving the chimney. It is impossible to allow gases to cool below 450-500 degrees in a fire tube boiler, and the temperature in a conventional furnace does not exceed 1100-1200 degrees. According to the Carnot formula, it turns out that you cannot get an efficiency higher than 63%, and even the efficiency of the furnace is not more than 80%, so the total is 50%, which is really bad.

In small domestic boilers, these features are less pronounced, because. with a decrease in the size of the boiler, the ratio of the surface of the register to the volume of flue gases in it increases, this is the so-called. square-cube law. In modern pyrosis boilers, the temperature in the combustion chamber reaches 1600 degrees, the efficiency of their furnace is under 100%, and the registers of branded boilers are made only thin-walled from heat-resistant special steel with a guarantee for 5 years or more. In them, gases can be allowed to cool to 180-250 degrees, and the overall efficiency reaches 85-86%

Note: cast iron for fire tubes is generally unsuitable, it cracks.

In water-tube registers, the coolant flows through pipes placed in a fire chamber, where hot gases enter. Now the temperature gradients and the square-cube law act in reverse: at 1000 degrees in the chamber, the outer surface of the pipes will be heated to only 400 degrees, and the inner surface to the temperature of the coolant. As a result, ordinary steel pipes serve for a long time and the boiler efficiency is about 80%.

But horizontal flow-through water tube boilers are prone to the so-called. "bubble". The water in the lower pipes is much hotter than in the upper ones. It is pushed through to the supply in the first place, the pressure drops, and the colder upper pipes “spit out” the water. "Whipping" not only gives noise, warmth and comfort as much as a neighbor - a drunkard and a brawler, but is also fraught with an impulse in the system due to water hammer.

Vertical water tube boilers do not fill, but if a water tube boiler is designed for the house, the register must be located on the chimney downstream, in the area where hot gases go from top to bottom. In a flow-type, with the same direction of movement of gases and coolant, a water-tube boiler, the efficiency drops sharply and soot is intensively deposited on the pipes near the supply, and it is generally unacceptable to make a return flow above the supply.

About the heat exchanger capacity

The ratio of the capacities of the heat exchanger and the entire cooling system is not taken arbitrarily. The rate of heat transfer from gases to water is not infinite, the water in the register must have time to take in heat before it leaves the system. On the other hand, the heated outer surface of the register gives off heat to the air, and it is wasted in the boiler room.

Too small a register is prone to boiling and requires precise, quick adjustment of the furnace power, which is unattainable in solid fuel boilers. The register of a large volume warms up for a long time and, with poor external thermal insulation of the boiler or its absence, loses a lot of heat, and the air in the boiler room can warm up above the permissible fire safety and technical specifications for the boiler.

The value of the capacity of the heat exchanger of solid fuel boilers ranges from 5-25% of the capacity of the system. This must be taken into account when choosing a boiler. For example, for heating, according to the calculation, only 30 sections of radiators (batteries) of 15 liters each were obtained. With water in the pipes and an expansion tank, the total capacity of the system will be about 470 liters. The capacity of the boiler register should be in the range of 23.5-117.5 liters.

Note: there is a rule - the greater the calorific value of solid fuel, the greater should be the relative capacity of the boiler register. Therefore, if the boiler is coal, the register capacity should be taken closer to the upper value, and for wood - to the lower one. For slow burning boilers, this rule is not valid; the capacity of their registers is calculated based on the highest efficiency of the boiler.

What is a heat exchanger made of?

Cast iron as a material for the boiler register does not meet modern requirements:

The low thermal conductivity of cast iron leads to low boiler efficiency, because. it is impossible to cool the exhaust gases below 450-500 degrees, as much heat will not pass through the cast iron into the water as needed.
The large heat capacity of cast iron is also its minus: the boiler must quickly give off heat to the system before it escapes somewhere else.
Cast iron heat exchangers do not fit into modern requirements by weight.

For example, let's take the M-140 section from an old Soviet cast-iron battery. Its surface area is 0.254 sq. m. For heating 80 sq. m. m. of living space you need a heat exchange surface in the boiler of about 3 sq. m, i.e. 12 sections. Have you seen a 12 cell battery? Imagine what a cauldron should be in which it will fit. And the load from it on the floor will definitely exceed the limit according to SNiP, and a separate foundation will have to be made under the boiler. In general, 1-2 cast-iron sections will go to the heat exchanger that feeds the hot water storage tank, but for the heating boiler, the issue of the cast-iron register can be considered closed.

The registers of modern factory boilers are made of heat-resistant and heat-resistant special steel, but production conditions are needed for their manufacture. The usual structural steel remains, but it corrodes very quickly at 400 degrees and above, so fire-tube boilers made of steel must be chosen for purchase or developed very carefully.

In addition, steel is a good conductor of heat. On the one hand, this is not bad, you can count on simple means to get a good efficiency. On the other hand, the return pipe must not be allowed to cool below 65 degrees, otherwise acid condensate from the flue gases will fall on the register in the boiler, which can eat through the pipes within an hour. You can eliminate the possibility of its deposition in 2 ways:

With a boiler power of up to 12 kW, a bypass valve between the boiler supply and return is sufficient.
With a higher power and / or a heated area of more than 160 sq. m, an elevator assembly is also needed, and the boiler must operate in the mode of overheating water under pressure.

The bypass valve is controlled either electrically from a temperature sensor or non-volatilely: from a bimetallic plate with a rod, from wax melting in a special container, etc. As soon as the return temperature drops below 70-75 degrees, it lets in hot water from submission.

The elevator unit, or simply the elevator (see Fig.) acts the other way around: the water in the boiler is heated to 110-120 degrees under pressure up to 6 atm, which eliminates boiling. To do this, the combustion temperature of the fuel is increased, which increases the efficiency and eliminates condensation. And before being fed into the system, hot water is diluted with a return pipe.

In both cases, forced circulation of water is necessary. However, it is quite possible to create a steel thermosiphon circulation boiler that does not require power supply for the circulation pump. Some designs will be discussed below.

Circulation and boiler

Thermosiphon (gravitational) circulation of water does not allow heating a room with an area of more than 50-60 square meters. m. The point is not only that it is difficult for water to squeeze through a developed system of pipes and radiators: if a drain valve is opened with a full expansion tank, water will rush in a strong stream. The fact is that the energy for pushing water through the pipes is taken from the fuel, and the efficiency of converting heat into motion in a thermosiphon system is scanty. Therefore, the efficiency of the boiler as a whole falls.

But the circulation pump needs electricity (50-200 W), which can be lost. UPS (uninterruptible power supply) for 12-24 hours battery life very expensive, therefore, a properly designed boiler is counted on forced circulation, and in the event of a power outage, it must switch to thermosyphon mode without outside interference, when the heating is barely warm, but still warm.

How is the boiler installed?

From the requirement of the minimum own heat capacity of the boiler, its small weight compared to the furnace and the weight load from it per unit floor area directly follow. As a rule, it does not exceed the minimum allowable according to SNiP for flooring 250 kg / sq. m. Therefore, the installation of the boiler is permissible without a foundation and even parsing the flooring, incl. and on the upper floors.

Place the boiler on a flat, stable surface. If the floor plays, it will still have to be disassembled at the installation site of the boiler to concrete screed with a side extension of at least 150 mm. The base under the boiler is covered with asbestos or basalt cardboard 4-6 mm thick, and a sheet of roofing iron 1.5-2 mm thick is placed on it. Further, if the flooring was disassembled, the bottom of the boiler is bricked up with a cement-sand mortar to the floor level.

Around the boiler protruding above the floor, thermal insulation is made, the same as under the bottom: asbestos or basalt cardboard, and iron on it. Removal of insulation to the sides of the boiler from 150 mm, and in front of the firebox door at least 300 mm. If the boiler allows additional loading of fuel until the previous portion burns out, then the removal in front of the furnace is needed from 600 mm. Under the boiler, which is placed directly on the floor, only thermal insulation is placed, covered with a steel sheet. Removal - as in the previous case.

For a solid fuel boiler, a separate boiler room is required. The requirements are listed above. In addition, almost all solid fuel boilers do not allow power adjustment over a wide range, so they need a full-fledged piping - a set of additional equipment that ensures efficient and trouble-free operation. We will talk about it further, but in general the boiler piping is a separate big topic. Here we mention only the immutable rules:

The installation of the piping is carried out in countercurrent to the water, from the return to the supply.
At the end of the installation, its correctness and quality of the connections are checked visually according to the scheme.
The installation of the heating system in the house is started only after tying the boiler.
Before loading fuel and, if required, applying power, the entire system is filled with cold water and during the day they control all joints for leakage. In this case, water is water, and not some other coolant.
If there are no leaks, or after they are eliminated, the boiler is started on water, continuously monitoring the temperature and pressure in the system.
Upon reaching the nominal temperature, the pressure is controlled for 15 minutes, it should not change by more than 0.2 bar, this process is called pressure testing.
After pressure testing, the boiler is extinguished, the system is allowed to cool completely.
Drain the water, fill in the regular coolant.
Once again, the joints are checked for leakage for a day. If everything is in order, start the boiler. No - eliminate leaks, and again daily control before starting.

Choosing a boiler

Now we know enough to choose a boiler based on the intended type of fuel and its purpose. Let's get started.

Wood

The calorific value of firewood is low, for the best - less than 5000 kcal / kg. Firewood burns quite quickly, releasing a large amount of volatile components that require afterburning. Therefore, it is better not to count on high efficiency on wood, but they can be found almost everywhere.

Wood burning in the house

A home wood-fired boiler can only be long burning, otherwise beats him on all counts. Industrial structures, eg. well-known KVR, cost from 50,000 rubles, which is still cheaper than building a furnace, do not require power supply and allow power adjustment for heating in the off-season. As a rule, they work both on coal and on any solid fuel, except for sawdust, but on coal, fuel consumption will be much higher: heat transfer from one load is 60-72 hours, and for specialized coal - up to 20 days.

However, a long-burning wood-burning boiler can be useful in places where there is no regular delivery of coal and a qualified heat engineering service. It costs one and a half times cheaper than coal, its shirt design is very reliable and allows you to build a thermosiphon heating system with an area of up to 100 square meters. m .. In combination with the smoldering of fuel with a thin layer and a rather large volume of the jacket, boiling of water is excluded, so the binding is quite the same as for titanium. Connecting a long-burning wood-fired boiler is also no more difficult than titanium, and can be done independently by an unskilled owner.

About brick boilers

Scheme of the device of the boiler "Blago"

Brick is a friend of the furnace and an enemy of the boiler due to the fact that it gives the structure a large thermal inertia and weight. Perhaps the only brick boiler in which the brick is in its place is the pyrolysis "Blago" Belyaev, the diagram in fig. And then, its role here is completely different: the lining of the combustion chamber is made of fireclay bricks. Heat exchanger water-tube horizontal; the problem of coiling is solved by the fact that the register pipes are single, flat, elongated in height.

The Belyaev boiler is really omnivorous, and 2 separate bunkers are provided for loading different types of fuel without stopping the boiler. On anthracite "Blago" can work for several days, on sawdust - up to a day.

Unfortunately, the Belyaev boiler is quite expensive, because of the fireclay lining it is poorly transportable and, like all pyrolysis boilers, requires complex and expensive piping. Its power is regulated within a small range by flue gas bypass, so it will show good efficiency on average per season only in places with prolonged severe frosts.

About boilers in the furnace

The boiler in the furnace, about which so much is being said and written now, is a water-tube heat exchanger immured in the furnace masonry, see fig. below. The idea is this: the stove after heating should give off heat more to the register than to the surrounding air. Let's say right away: reports of an efficiency of 80-90% are not only doubtful, but simply fantastic. The best brick oven itself has an efficiency of no higher than 75%, and its outer surface area will be at least 10-12 square meters. m. The surface area of the register is hardly more than 5 square meters. m. In total, less than half of the heat accumulated by the furnace will go into the water, and the overall efficiency will be below 40%

The next moment - an oven with a register immediately loses its property. In no case should you drown it out of season with an empty register. The TC (temperature coefficient of expansion) of the metal is much greater than that of a brick, and the heat exchanger swollen from overheating will tear the furnace before our eyes. Thermal seams will not help the case, the register is not a sheet or a beam, but a three-dimensional structure, and it bursts immediately in all directions.

There are other nuances here, but the general conclusion is unambiguous: a stove is a stove, and a boiler is a boiler. And the fruit of their violent unnatural union will not be viable.

Boiler piping

Boilers that exclude boiling water (jacketed long-burning, titanium) cannot be made for a power of more than 15-20 kW and stretched in height. Therefore, they always provide heating of their area in the thermosiphon mode, although the circulation pump, of course, will not interfere. Their piping, in addition to the expansion tank, includes only an air drain valve at the highest point of the supply pipeline and a drain valve at the lowest return point.

The piping of solid fuel boilers of other types should provide a set of functions, which is better understood in fig. on right:

safety group: air drain cock, common pressure gauge and breakthrough valve to release steam when boiling;
emergency cooling storage tank;
its float valve, the same as in the toilet;
thermal valve for starting emergency cooling with its sensor;
MAG-block - a drain valve, an emergency drain valve and a pressure gauge, assembled in one housing and connected to a membrane expansion tank;
forced circulation unit with a check valve, a circulation pump and a three-way bypass valve electrically controlled by temperature;
intercooler - emergency cooling radiator.

Pos. 2-4 and 7 make up the power reset group. As already mentioned, solid fuel boilers are regulated in terms of power within small limits, and in case of sudden warming, the entire system can overheat unacceptably, up to a gust. Then the thermal valve 4 lets tap water into the intercooler, and it cools the supply to normal.

Note: the master's money for fuel and water at the same time quietly flowing down the drain. Therefore, solid fuel boilers are unsuitable for places with mild winters and long off-seasons.

The forced circulation group in normal mode bypasses part of the supply to the return line so that its temperature does not fall below 65 degrees, see above. When the power is turned off, the thermal valve closes. As much water enters the heating radiators as they let through in the thermosyphon mode, if only it was possible to live in the rooms. But the intercooler thermal valve opens completely (it is kept closed under voltage), and the excess heat again takes the owner's money into the drain.

Note: if water is lost along with electricity, the boiler must be urgently extinguished. When the water from tank 2 flows out, the system will boil.

Boilers with built-in overheating protection are 10-12% more expensive than conventional ones, but this more than pays off by simplifying the piping and increasing the reliability of the boiler: excess superheated water is poured into an open large-capacity expansion tank, see Fig. return line. The system, except for the circulation pump 7, is non-volatile and goes into the thermosiphon mode smoothly, but with a sudden warming, the fuel is still wasted, and the expansion tank must be installed in the attic.

As for pyrolysis boilers, we present a typical scheme for their piping for reference only. Anyway, its professional installation will cost only a small part of the cost of the component. For reference: a heat accumulator alone for a 20 kW boiler costs about $5,000.

Note: membrane expansion tanks, unlike open ones, are installed on the return line at its lowest point.

Chimneys for boilers

Chimneys of solid fuel boilers are generally calculated in the same way as stoves. General principle: too narrow a chimney will not give the desired draft. For the boiler, this is especially dangerous, because. it is heated continuously and the waste can go at night. Too wide a chimney leads to a “whistling”: cold air descends through it into the furnace, chilling the stove or register.

The boiler chimney must meet the following requirements: the distance from the roof ridge and between different chimneys is at least 1.5 mm, the upward extension above the ridge is also at least 1.5 m. Safe access to the chimney must be provided on the roof at any time of the year. At each break in the chimney outside the boiler room there must be a cleaning door, each passage of the pipe through the ceiling must be thermally insulated. The upper end of the pipe must be equipped with an aerodynamic cap; for the chimney of the boiler, it, unlike the stove, is mandatory. Also, a condensate collector is required for the boiler chimney.

In general, the calculation of the chimney for the boiler is somewhat simpler than for the furnace, because. the boiler chimney is not so winding, the heat exchanger is simply considered a lattice barrier. Therefore, it is possible to build generalized graphs for different design cases, for example. for a chimney with a horizontal section (flue) of 2 m and a condensate collector 1.5 m deep, see fig.

According to such graphs, after an accurate calculation according to local data, it is possible to estimate whether there was blunder. If the calculated point is somewhere around its generalized curve, the calculation is correct. In extreme cases, you will have to build up or cut the pipe by 0.3-0.5 m.

Note: if, say, for a pipe with a height of 12 m there is no curve for a power of less than 9 kW, this does not mean that a 9 kW boiler cannot be operated with a shorter pipe. It’s just that for lower pipes, a generalized calculation is no longer possible, and you need to calculate exactly according to local data.

Video: an example of the construction of a mine-type solid fuel boiler

conclusions

The depletion of energy resources and the rise in fuel prices have radically changed the approach to the design of domestic heating boilers. Now from them, as well as from industrial ones, high efficiency, low thermal inertia and the possibility of operational power control over a wide range are required.

In our time heating boilers according to the basic principles laid down in them, they finally diverged from the furnaces and divided into groups for different climatic conditions. In particular, considered solid fuel boilers are suitable for areas with a harsh climate and prolonged severe frosts. For places with a different climate, other types of heaters will be preferable.

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Before proceeding with the independent manufacture of solid fuel boilers, it is necessary to prepare sketches. They should reflect the main and additional elements. It is proposed to take drawings of solid fuel boilers for long burning as a basis. It is quite possible to make them with your own hands.

Appearance homemade design

Analogues with support for long burning differ from conventional boilers by the presence of two working chambers at once. In the first of them, the directly deposited fuel is burned, and in the second, the released gases are burned. An important role is played by the timely supply of oxygen. As a device for blowing air, a conventional fan with simple automation can be used.

Among the advantages of the units it should be noted:

the minimum number of bookmarks of fuel;
high work efficiency;
usage various kinds solid fuel;
a small amount of soot in the pipes during operation;
design reliability.

Note! Of the disadvantages, it is necessary to mention the complexity self-manufacturing. Although when using ready-made drawings of solid fuel boilers for long burning with your own hands, it is still possible to make a unit.

The process of manufacturing solid fuel boilers for long burning with your own hands: drawings and assembly

It should immediately be noted that structures can have both an upper gas combustion chamber and a lower one. In the first case, the combustion products enter the working compartment under the influence of natural forces, and in the second case, with the help of an additional air injection device.

Since boilers with a lower afterburner are difficult to manufacture and require the installation of additional equipment during installation, it does not make much sense to consider them. It is faster and more economical to make a design with an upper chamber for burning gases.

Applicable Items

For the manufacture of the structure you will need:

pipe with a section of 500 mm and a length of 1300 mm;
pipe with a diameter of 450 mm and a length of 1500 mm;
pipe with a section of 60 mm and a length of 1200 mm;
two rings 25 mm wide and 500 mm in diameter;
metal corners and pieces of channel;
Metal sheet;
asbestos cloth;
hinges and handles.

Chassis assembly order

First of all, pipes with a cross section of 1500 and 1300 mm are inserted into each other. They are connected using a ring made from a corner measuring 25x25 mm. A circle with a diameter of 450 mm is cut out of a metal sheet and fixed to the end of the pipe. It acts as the bottom. The result should be a small barrel.

A hole in the shape of a rectangle 15x10 cm is cut out from the bottom side of the structure for the ash pan door. The sash is attached to the opening with the help of a loop, and a valve is also installed.

A rectangular hole for the fuel chamber is made a little higher. Dimensions can be determined by yourself. The convenience of loading firewood or other fuel will depend on the correctly selected dimensions. Using the same technology, a door with a latch is installed.

At the top of the homemade structure, an exhaust pipe is made, through which the exhaust gases will flow into the chimney. On the sides, by welding, the pipes necessary for connecting to the heating system of the building are fixed. They must be threaded.

Air distributor device

A circle is cut out of a piece of tin with a cross section 20-30 mm smaller than the diameter of the inner part of the boiler. In the central part, a round hole is made for the air distribution pipe. Its diameter should be 6 cm. A pipe is inserted directly into the hole and welded to the base.

Pieces of a corner are attached to the bottom of the metal pancake. On the other hand, a loop is fixed by welding, which is necessary to move the structure up and down. To adjust the air supply directly to the combustion chamber, a damper is arranged.

A circle with a diameter of 500 mm, cut from a suitable piece of metal, is inserted into the structure. The upper end of the pipe is inserted into the hole, after which the upper cover of the boiler is welded tightly. A cable is fixed to the loop, allowing the distributor to be lowered and raised.

Note! The simplest of all the schemes of long-burning solid fuel boilers was presented. Assemble with your own hands robust design it is not so difficult, especially if you have experience with welding and other tools.

Do-it-yourself solid fuel boiler for long burning: video for review

Another option is to use a gas cylinder for the hull. From it you can create a completely effective design for heating buildings. small size. To get acquainted with the features homemade device for heating it is suggested to look at the video. Do-it-yourself long-burning boiler without drawings can be made according to it.

Are there any negative reviews about the solid fuel boiler for long burning?

Sometimes consumers leave negative reviews about designs, but they are more likely related to common disadvantages, which are inherent in solid fuel devices in general.

The following shortcomings can be distinguished:

for fuel storage it is necessary to use special premises or structures;
in any case, fuel must be loaded manually, despite the reduced number of loads;
when installing any models of solid fuel boilers, special safety measures must be taken;
It is impossible to regulate the process of fuel combustion in the combustion chamber with particular accuracy.

Note! There are a lot of minuses, but still solid fuel boilers are the only way out of a situation where gas and electricity main lines are not available.

On the cost of finished models for heating with solid fuel

If it is not possible to make a long-burning boiler or simply there is no desire, then you can purchase a finished design. It must be recognized that models for heating large rooms will be expensive. In the table you can see the prices for Stropuva boilers.

Article

At cottages and country houses without autonomous heating systems based on boilers different kind not enough. We must pay tribute to manufacturers who offer efficient models with automation and a large range of options. But for heating small country houses or greenhouses, the installation of expensive equipment is impractical, since it will be cheaper to make a heating boiler on your own. According to the main characteristics, it will be no worse than the factory models.

The choice of the type of home-made heating boiler depends on what fuel it will run on. Hence the classification:

TO electric boilers heating does not have high safety requirements. The design consists of a container, which is easy to make from a pipe segment with a diameter greater than that of the inlet pipes of the heating system. Heating elements are installed inside. Despite the ease of manufacture, such a boiler for heating is not economically viable, since the price of electricity is high. Therefore, this option is chosen for periodic heating of small country houses.
Gas boilers have high efficiency and low fuel prices. However, due to the explosiveness of gas, the requirements even for factory models are very high. Therefore, it is almost impossible to obtain permission to install and operate a home-made heating boiler, and theoretically when installed in the basement.
There is nothing complicated in the manufacture of a liquid fuel boiler with your own hands. But for normal operation, it will be necessary to install a container for storing fuel oil or diesel fuel and lay an insulated pipeline from it. The price of the burner and the difficulty of setting it up can discourage the desire to make such a boiler. Moreover, you will have to negotiate with the fire inspectorate about obtaining permission to install.
Most often, a solid fuel heating boiler is installed for heating a private house. It is heated with wood coal, peat, oil shale. For home-made boilers of this type, the outlet temperature reaches 120 - 150 ⁰C.

The design of a solid fuel and pyrolysis boiler

A traditional solid fuel heating boiler works like a conventional stove. It is assembled from two steel or cast iron containers inserted one into the other. In the inner (furnace) firewood is burned, in the outer (tank) water is heated. The design consists of the following parts:

fireboxes with a door;
grate;
ash pan with a door;
soot collector;
chimney;
gate valve;
branch pipes for connecting the supply and return pipelines of the heating system;
legs;
lids for closing the heating tank.

Outside air enters the furnace through the ash pan and grate. The intensity of combustion is regulated by the size of the door opening. Traction can be natural or forced. A properly designed and made heating boiler has an efficiency of up to 79%.

Advantages of classic solid fuel boilers:

low cost of fuel;
does not require electricity to work;
fuel versatility;
the possibility of burning wood waste.

But when choosing this type of boilers, the disadvantages should be taken into account:

one load of fuel is enough for a maximum of 6 hours;
a place is required for storing fuel;
the complexity of care, since you will have to regularly remove combustion products;
the combustion of solid fuel is inertial, so there are difficulties with regulation.

Pyrolysis boilers for heating, according to the principle of operation, they differ from the classical version in that not only the fuel burns, but also the gases released from it. The design consists of the following parts:

afterburning chambers with built-in nozzle;
gasification chamber;
air supply systems;
chimney system with throttle;
heat exchanger;
water circulation systems;
temperature sensor and pressure gauge;
safety valve.

To kindle the boiler, the gasifying chamber is filled with firewood through the top door. After igniting the kindling with an open throttle, a fan is started on the chimney. When the firewood flares up, the door is closed and the throttle is closed. Due to the reduction in the amount of air supplied, the wood begins to smolder at a temperature sufficient to start the pyrolysis reaction. The emitted gases after passing through the nozzle are mixed with the secondary air in the combustion chamber, ignite, heating up to a temperature of 1100⁰C, and sent to the heat exchanger.

On a boiler without a smoke exhauster, before adding firewood, open the throttle on the chimney, wait for some time required to remove the pyrolysis gas. After loading the fuel, closing the door and the throttle valve, the boiler continues to operate normally.

Compared to conventional heating boilers, pyrolysis boilers have many advantages:

due to complete combustion, there is no need for frequent cleaning of the ash pan and gas ducts;
ease of control of the intensity of combustion;
duration of work without adding fuel from 5 hours to several days;
the possibility of burning uncut firewood;
the use of scraps from fiberboard, chipboard, MDF and plywood as fuel;
in pyrolysis heating boilers, the content of harmful compounds in the smoke is 3 times less.

However, there are also disadvantages:

Since the fan or exhauster is powered by electricity, an uninterruptible power supply may be required.
When using fuel with a moisture content above 20%, efficiency is reduced.
At low loads, malfunctions are possible, which cause an increase in tar deposits in the gas ducts. To normalize the operation of the boiler, heat accumulators are installed into which excess heat is removed.
To prevent the formation of condensate on the walls of the heat exchanger, which accelerates the corrosion process, the water temperature in the heating return must be at least 60⁰C.
Due to the high material consumption, the costs are 2 times higher than for conventional boilers.

A traditional solid fuel heating boiler works like a conventional stove. Pyrolysis boilers for heating according to the principle of operation differ from the classical version in that not only the fuel is burned, but also the gases released from it.

Do-it-yourself pyrolysis boiler for heating

If you weld a heating boiler at an amateur level, then emergency situations during operation are provided. Therefore, without good skills, it is better not to take a job.

Calculation of power and dimensions of the boiler

Making a heating boiler with your own hands begins with determining the dimensions, which depend on the amount of power sufficient for heating. When calculating, it is assumed that 1 kW of power is needed per 10 m² of heated area. It is easy to calculate that for heating a house with an area of 300 m², a boiler with a capacity of at least 30 kW is required. To compensate for heat loss, a small margin is needed.

It is unlikely that it will be possible to correctly design a pyrolysis heating boiler from scratch without knowledge of heat engineering. Therefore, it is better to find a ready-made drawing on the Internet for the required power. It is desirable that the service life of the unit made according to this project was not 1 year. If necessary, you can contact the author to clarify unclear points.

Necessary tools and materials

To work, you need to stock up on the following tools:

electric drill and drills;
grinder with circles;
gas cutter for cutting large holes;
set of plumbing tools.

As well as materials:

sheet steel 5 mm thick for the manufacture of chambers and 4 mm for the outer skin;
round pipe 57x3.5 for the heat exchanger and 159x4.5 for the hog (horizontal section of the chimney at the outlet of the boiler);
fireclay bricks;
round pipe 32x4.5;
corrugated pipe 80x30x2 and 80x40x2;
steel strip 30x4 mm;
fan;
thermometer and manometer.

The amount of materials is calculated according to the drawing.

Manufacturing process

To save time, it is advisable to chop sheet metal blanks on a guillotine, since it is difficult for a grinder to make a perfect cut. This service is provided to buyers at metal depots. A homemade heating boiler is made in the following order:

A gas and a combustion chamber are welded from blanks.
Air ducts from a professional pipe 60x30x2 with pre-drilled holes with a diameter of 10 mm are welded to the side walls of the gas chamber. At the back, a cutout is made for the chimney.
A tube is led into the combustion chamber through which secondary air will be supplied. It is connected to the front side of the boiler with a 20x20 profile.
The heat exchanger is made from two blanks, in which 2 rows of holes for gas outlet pipes with a diameter of 57 mm are cut. After cutting to size and setting in place, they are scalded.
The finished heat exchanger is installed in place.
Make and install a chimney damper.
The front wall of the chambers is welded with pre-made holes for pipes through which primary and secondary air will be supplied.
At the place where the gas duct exits and the throttle is installed, the back wall and burs are welded.
After cleaning the welds, the inner box is ready.
To fix the outer skin to the box, segments of corners with a shelf of 25 mm are welded.
On the skin in places where the corners are installed, holes with a diameter of 10 - 12 mm are drilled.
Through the holes, the skin is welded to the corners on all sides of the box, except for the top.
To check the tightness of the joints, plug all the holes, pour water through the top. Leaks are marked with chalk.
The air dampers are adjusted with threaded studs. Then the air holes are closed with a casing with an air duct from a professional pipe.
They make and hang doors on the cameras. They are lined with cast iron plates or fireclay bricks.
The bottom of the gas chamber is laid out with sawn bricks.
To fix the fan, a flange is welded to the end of the duct pipe.
The lining of the combustion chamber is made of fireclay bricks.
To improve heat transfer and ease of cleaning, it is recommended to install swirlers (turbolizers) in the gas ducts.
The boiler is tested for leaks with a pressure of 4 bar, which is created by a pressure tester after filling with water. If the pressure does not drop within half an hour, the boiler is ready for operation. Otherwise, you need to look for a leak.
To prevent emergency situations, a safety group is installed on the supply pipeline of the heating system, consisting of a pressure gauge, a safety valve, and an air vent.
If desired, the pyrolysis boiler can be easily equipped with an automatic control system.

Connection and commissioning

Before starting, the heating boiler is connected to an external chimney and filled with water. To control its temperature, a thermometer must be installed. The boiler is put into operation in the following sequence:

Connect the power cable to the fan, check the quality of its work. The air dampers should be in the middle position.
Some paper is placed in the gas chamber, a few poles on top, and the door is closed.
The throttle on the chimney is opened to failure, the fan is started, the paper is set on fire.
After the firewood is lit, the throttle is closed.
Through the lower door, the ignition of pyrolysis gases is monitored. If the torch does not ignite, the amount of air supplied to the gasification compartment is reduced, and the amount of air supplied to the combustion chamber is increased.
When the torch lights up, adjust the intensity of the flame, achieving a white-yellow color with the help of air dampers.
After closing the door, the time until the water boils is noted. At a temperature of 100⁰C, the fan is stopped. The torch should go out.

We make a boiler from a solid fuel pipe

It does not take much time to make a boiler from a pipe with your own hands. Unlike a rectangular sheet steel structure, this option is more reliable, as it is assembled with fewer welds.

What you need to make

Getting started, you need to stock up on the necessary tools:

welding machine and electrodes;
gas cutter;
grinder;
set of plumbing tools.

And material:

a piece of pipe with a diameter of 425 mm for the body, as well as 100 and 25 mm;
sheet steel 4 mm thick;
two nozzles 25 mm;
hinges for hanging doors;
corner 25 mm;
reinforcing bars with a diameter of 8 mm.

Step by step manufacturing process

First, prepare the parts from which the boiler will be assembled from the pipe:

A piece 1–1.2 m long is cut from a pipe with a diameter of 425 mm. This will be the body of a vertical heating boiler.
Two rectangular holes are cut out on the pipe. For a firebox with a size of 200x100 mm, for a blower 200x30 mm at a distance of 50 mm from each other. Doors are made from cut pieces. The distance from the lower edge of the body to the blower is 50 - 70 mm.
On the side in the upper part of the case, 2 holes with a diameter of 25 mm are cut one under the other. The lower one is at a distance of 150 mm from the firebox door for the return pipe, and the upper one is 50 mm from the top of the housing for supplying the heating system.
From sheet steel, cut out 2 circles with a diameter of 425 mm for the housing covers and 1 with a diameter of 412 mm for the partition between the furnace and the tank.
In the top cover and partition, holes are made for the chimney, which is made from a 100 mm pipe.
The legs are made from pipe 25.
A grate in the form of a lattice is welded from reinforcing bars.

When all the parts are ready, proceed to the assembly:

A chimney is welded to the partition and installed on reinforcement supports stuck inside the body at a distance of 300 - 350 mm from the furnace. Then they are welded on both sides.
At the end of the chimney put on the top cover. Both joints are welded.
A grate is inserted from the bottom of the body. Then, segments of the corner 25 are welded on which it will stand.
The bottom cover is welded, and legs 50 mm high are welded to it.
Hinges are welded, the doors of the blower and firebox are hung.

Connection and first kindling

The finished boiler for heating is checked for leaks. To do this, a plug is installed on the lower pipe. Water is poured through the top. If there are no leaks, the boiler is connected to the heating system.

The chimney is best brought out strictly vertically. If this is not possible, it is mounted with a minimum number of bends. Horizontal sections are installed with a slope of at least 0.1% of the length.

For the first kindling, a small amount of firewood or coal is enough. Otherwise, with a sharp increase in temperature, tar deposits will begin on the walls of the chimney. Therefore, due to a decrease in the passage, traction will become worse.

To ensure that a sufficient amount of air enters the furnace, the position of the blower door is adjusted. More convenient for this purpose is a slide gate, which you can buy or make yourself.

Self-welded boilers for heating are not recommended for installation in a residential area, since, unlike factory models, they do not have a guarantee of safe operation. In the event of an emergency, you will have to answer for the consequences yourself. But even when installed in a separate room, fire safety rules must be strictly observed.

From the author: Greetings, dear friends! Many owners country houses appreciate individual approach to the creation of a heating system, almost always preference is given to home-made equipment. How to make a water heating boiler with your own hands, taking into account safety precautions and maximum efficiency? In the article we will study the topic of assembly and installation of several types of devices.

For heating private houses and cottages, experts advise using exclusively safe types of fuel, namely: electricity, coal, wood or pellets.

Note that in this material you will not find instructions for assembling gas and diesel boilers, since their installation in the house is prohibited. The competent authorities will not allow the boiler that you have assembled yourself to be inserted into the gas pipe circuit. If such violations are discovered “backdating”, then you, as the owner of the living space, will be brought to administrative responsibility.

Advantages of manual assembly

Why do experienced craftsmen advise you to assemble boilers for the heating system yourself? These devices have certain pros and cons, but there are still more advantages. So, a hand-assembled heating boiler will be cheaper than its factory counterpart, however, the latter will show a higher efficiency.

The principle of operation of such equipment, regardless of what it works on, is quite simple. When fuel burns, it releases heat energy. It enters the heat exchanger and warms up the water circulating in the system.

The scheme of operation of the boiler, its external parameters and characteristics directly depend on two main factors:

what materials will you use to make the boiler;
what type of fuel is most affordable in your area.

And yet, back to the shortcomings of boilers, which are assembled according to their own drawings. First of all, this is the lack of a guarantee that the boiler will serve you faithfully without unpleasant surprises. The factory boiler can always be returned or exchanged for a new one until the warranty period has expired. The owner in this respect can be calm. The quality of the work of a home-made boiler depends only on your qualifications and what parts were used in its assembly.

However, hand-assembled boilers also have a very important advantage - this is a focus on the individual needs of your household. In this regard, everything depends only on you.

Efficiency

Experts say that the quality of the heating boiler depends on two main factors:

heat exchanger device. The amount of heat that is transferred to this very coolant (usually water) directly depends on the area of \u200b\u200bdirect thermal contact between the container with the coolant and the furnace;
fuel burnout. With an unsuccessful boiler design, pyrolysis gas can escape into the pipe along with combustion products. The fact is that when it is afterburned, the efficiency of the unit increases significantly. Another sign of an ill-conceived assembly of a heating boiler is an insufficient supply of oxygen to the combustion chamber.

We draw conclusions:

when designing a boiler for water heating, the master must take care of the maximum low temperature of the combustion products. This indicator is inversely proportional to the efficiency of the device;
Strive to ensure the safety and durability of the boiler? Then take care of the same indicator - the temperature of the combustion products. The lower it is, the better;
for factory models of boilers, this figure ranges from +120 to +150 degrees.

How is a water boiler

You already know about the principle of operation of boilers for water heating of a home, both factory-made and home-made. It is implemented in two main ways:

water boiler of the "samovar" type. In this design, the fuel burns out inside a container with a coolant (water). Usually this type of boiler is used in Russian baths;
water boiler with coil. In it, the coolant flows through the pipes of the heat exchanger laid through the furnace. This type of boiler has a popular variety, in which the coil does not pass through the furnace, but directly behind it - where the combustion products come out.

The master himself decides which type of boilers to give preference to. His choice depends on the availability of materials necessary for assembly, his own skills and the characteristics of the operation of the device. Whatever type of boilers you take as a basis, it is important to remember that this unit is a device of increased danger!

Remember that home heating boilers require a thermometer to determine the temperature of the water in the system, a pressure gauge to measure pressure, and a valve that is used to relieve high pressure (if necessary).

Preparing for production

Before understanding the question of how to connect a self-assembled heating boiler, it is important to understand what tools and materials you will need for assembly and installation.

Boilers are usually made of sheet steel. The optimum material thickness is 4–5 mm. If you can afford it, go for the heat resistant variety. Given that it is quite expensive, many craftsmen take ordinary stainless steel.

The first step preceding the development of the scheme of the future unit is to determine the method of circulation of the coolant through the heating system. If the water moves on its own, using the principle of gravitational circulation, then the water tank will need to be raised to a fairly large height. In this case, you will need pipes of large diameter throughout I. If the pipe diameter is not large enough, then you can not do without installing a circulation pump.

It is worth briefly describing the features of the operation of a heating system with forced circulation of the coolant. She has both advantages and disadvantages. The pipes used in this system have a small diameter, which means they are cheaper. In addition, the tank that warms up the coolant does not need to be raised high. These were pluses, and among the minuses one can note the dependence of the system on the availability of electricity. The boiler can simply explode if the power goes out in your house.

Pro tips:

heating circuits and pipes welded to the boiler are recommended to be made from pipes with a diameter of at least 32 mm;
considering that during an emergency stop of the circulation pump, the water temperature rises sharply, and its movement slows down, you should take care of the health of the heating circuit. It is better to assemble it using galvanized pipes. Do not forget to ensure the tightness of the mating thread with red lead and linen tow.

Types of boilers

Homemade heating boilers are usually classified depending on what fuel they use. The wood burning boiler is most in demand for self assembly due to its simple design, the availability of materials and tools needed for its manufacture. In addition, firewood is a fairly inexpensive fuel, and you can buy it in the right amount in almost any region. The advantages of a wood-burning boiler include versatility and simplicity, the disadvantages are a rather low efficiency.

The simplest version of such a unit is as follows: a tube that acts as a firebox is inserted inside another tube (larger diameter) with thick walls. The cavity between them is filled with water. Note that wood-burning boilers can be safely fired with other types of solid fuels, namely: coal, peat briquettes.

A pyrolysis boiler is more efficient than a wood-burning boiler, although it runs on the same fuel - wood. The fact is that if you burn a tree with a lack of oxygen at a temperature of +200 to +800 degrees, then it will decompose into two elements: pyrolysis gas and wood coke. If oxygen is added to the gas, then ignition will occur with intense heat release.

Thus, it is possible to increase the efficiency of a home-made boiler up to 92%. A portion of firewood that burns in a wood-burning boiler for 4 hours will give off heat energy in a pyrolysis boiler 3 times longer. The advantages of this design include the absence of solid residues after combustion and the possibility of adjusting the combustion of gases in automatic mode.

This type of heating units also has disadvantages: it is important to comply with the requirements for the moisture content of firewood (no more than 30%), and the materials for the manufacture of such a stove will cost much more than for a wood-burning counterpart. True, the cost of the boiler should pay off pretty quickly.

In boilers running on waste oil, diesel fuel can also be used as fuel. The principle of their operation is as follows: oil drips onto a hot pan and evaporates, transforming into gases, and those, burning, heat the coolant.

They consist of a heating element placed inside the tube. The tube is vertical. From above, a supply is connected to it, and from below - a return. Water circulates naturally.

Tools and materials

It is quite simple to make a water heating boiler with your own hands, in addition, you will not need to purchase any special tools, equipment or parts that are difficult to find on sale. Everything you need for work, most likely, you will find in your workshop, namely:

sheet metal ( metal barrel, a pipe of decent diameter, an old stove);
steel pipes;
shaped pipes or radiators (if you chose water as a coolant);
bolts, nuts;
dampers (you can make it yourself or buy it, used ones will do);
door.

As mentioned above, it is important to install the very minimum of automation on the boiler: a pressure gauge, a thermometer. Make sure that the materials you select have no flaws and are of good quality - no traces of rust, holes. Experts recommend supplementing the boiler with a pump that would be responsible for the circulation of the coolant.

We suggest that you familiarize yourself with the video on assembling a boiler for water heating of a private house with your own hands.

Installation in a brick oven

Suppose you want to place a hot water boiler inside. In this case, the step-by-step algorithm of your actions will look like this.

Consider the location of the boiler installation.
Mark up and prepare the foundation.
It is necessary to prepare the solution needed for laying bricks. Take sand and clay in a ratio of 2:1. Please note that the percentage constituent parts the solution will depend on the quality of the clay. Clay should be soaked overnight, then mixed using a special nozzle on a drill.
When the foundation is ready, it's time to take care of waterproofing. You can use a roofing sheet for this. How to pick it up? The dimensions of the sheet must be at least 10 cm larger than the dimensions of the boiler.
The roofing material must be poured with a cement screed and leveled.
The outer contour of the future stove is laid out with red brick. Silicate is not suitable for these purposes. You can also put a fight inside the structure.
The wall must be brought to the level of the blower door. Next, lay the metal sheet at an angle outward. This is necessary to make it easier to extract the ashes.
The next step is to mount the door.
Now you can lay out the contour of the blower.
Install the boiler itself and the furnace door.
The last step is to lay out the chimney, and you can begin to operate.

https://www.youtube.com/watch?v=g3vQT3uUKwM

Summing up, we note that the manufacture and installation of a boiler for a water heating system is quite feasible work for experienced craftsman. You can find a lot of sensible training videos on the network on this issue. We hope that this material will be useful to you, and you will cope with the task perfectly well. Good luck and see you soon!