In an effort to save on heating, many home “do-it-yourselfers” make various devices. A DIY boiler, which can often be seen in a private home, is one such useful device.
There are various varieties of it. If you have the skills to work with a welding machine and metal, you can save significantly on heating installations.
Advantages of a home-made heating boiler
A do-it-yourself water boiler is simply indispensable for a country home, where heating costs are often too high.
A DIY wood-fired water boiler for the stove is an excellent alternative to gas. and it will also significantly save hot water. When it comes to a country house, not all houses are connected to gas heating, and connecting it is also not a cheap pleasure. Of course, the problem can be solved in another way by purchasing an electric model for heating in the store, but it is also very expensive, and the cost of electricity will also increase if it is installed.
A model created with one’s own hands may not be inferior to factory models in terms of power and efficiency, and sometimes even surpasses them many times over. If you work strictly according to the instructions and make all the calculations correctly, then you will definitely not be disappointed with the result.
When starting work, do not forget about the correct calculation of temperature, and also choose not too thin sheets of metal so that it does not burn out. In addition, as a material for work, you can take old used boilers or based on a finished wood-burning stove.
Key advantages of a hand-made water boiler for heating a furnace:
- environmental friendliness;
- good efficiency indicator;
- low cost of materials and fuel;
- safety;
- acceptable working conditions;
- standalone installation.
Varieties
Before directly manufacturing a boiler for heating a house, you need to decide on its configuration and type. Depending on the type of coolant heating, boilers are:
- Gas;
- Wood-burning;
- Coal;
- Electrical;
- Pyrolysis;
- Oily;
- Pellet
As for the configuration, it can be anything:
- Round;
- Rectangular;
- Trapezoidal;
- Conical
Build process
The process of creating a boiler includes several stages. When manufacturing each element, it is worth taking into account the special operating conditions of the product being manufactured.
Air supply device
We cut a section from a thick-walled pipe with a diameter of 100 mm, the length of which will be equal to the height of the firebox. We weld a bolt to the bottom. From a steel sheet we cut out a circle with the same diameter as the pipe or larger. We drill a hole in the circle large enough to pass the bolt welded to the pipe. We connect the circle and the air duct pipe by tightening the nut onto the bolt.
As a result, we will get an air supply pipe, the lower part of which can be closed by a freely moving metal circle. During operation, this will allow you to regulate the intensity of firewood combustion and, consequently, the temperature in the room.
Using a grinder and a metal disc, we make vertical slits approximately 10 mm thick in the pipe. Through them, air will flow into the combustion chamber.
Housing (firebox)
The body will require a cylinder with a sealed bottom with a diameter of 400 mm and a length of 1000 mm. The dimensions may be different, depending on the available free space, but sufficient for laying firewood. You can use a ready-made barrel or weld the bottom to a thick-walled steel cylinder.
Sometimes heating boilers are made from gas cylinders for a longer service life.
In the upper part of the body we form a hole for the removal of gases. Its diameter must be at least 100 mm. We weld a pipe to the hole through which the exhaust gases will be removed.
The length of the pipe is selected depending on design considerations.
Connecting the housing and the air supply device
We cut a hole in the bottom of the housing with a diameter equal to the diameter of the air supply pipe. We insert the pipe inside the body so that the air vent extends beyond the bottom.
The air supply pipe should end a few centimeters before the start of the chimney.
Heat Dissipation Disc
We cut out a circle from a metal sheet 10 mm thick, the size of which is slightly smaller than the diameter of the body. We weld a handle made of reinforcement or steel wire to it.
This will greatly simplify the subsequent operation of the boiler.
Convection hood
We make a cylinder from sheet steel or cut a piece of pipe, the diameter of which is several centimeters larger than the outer diameter of the firebox (body). You can use a pipe with a diameter of 500 mm. We connect the convection casing and firebox together.
This can be done using metal jumpers welded to the inner surface of the casing and the outer surface of the firebox, if the gap is large enough. With a smaller gap, you can weld the casing to the firebox around the entire perimeter.
From a steel sheet we cut out a circle with the same diameter as the firebox or a little larger. We weld the handles to it using electrodes, wire or other available means.
Considering that the handles can become very hot during operation of the boiler, it is worth providing special protection made of material with low thermal conductivity.
To ensure long burning, we weld the legs to the bottom. Their height should be sufficient to raise the wood-burning boiler at least 25 cm above the floor level. To do this, you can use various rolled products (channels, angles).
Congratulations, you have made your own wood-burning boiler. You can start heating your home. To do this, just load the wood and light it by opening the lid and heat dissipation disk.
Ash pan
To cut a hole for the ash pan, previously applied markings are used. The door is made separately from sheet metal: it is fixed to the body with brackets. To make it convenient to open and close the door, it is equipped with an improvised handle made of a metal rod or thick wire.
What does a boiler consist of and how does it work?
The fuel in such boilers burns much longer than in conventional units. This is due to their operating principle, which involves burning wood in the firebox from top to bottom. The combustion chamber is cylindrical in shape and is completely loaded with wood through a door at the top of the housing. Ignition is carried out through the same door; the design of long-burning solid fuel boilers is such that air is also supplied to the combustion zone from above through a vertical pipe. A flat round weight made of thick metal (10-15 mm) is attached to the end of this pipe; arc-shaped air distributors made of strip metal are welded to it from below. A similar design can also be used to make a sawdust boiler.
Weight for a homemade boiler
The size of the load is 5 mm smaller than the internal diameter of the firebox cylinder, which allows the structure to move up and down. The other end of the pipe passes through the upper wall of the boiler; a damper is installed on it, with which the amount of air can be adjusted manually. The length of the pipe is 15-20 cm greater than the height of the combustion chamber. The latter can be arbitrary; home-made long-burning units work the longer, the larger the diameter and height of the firebox. At the same time, the volume of the unit’s water jacket and its thermal power increase.
Long burning boiler design
After ignition, the pipe with a load is lowered, pressing down the array of firewood. The air enters directly into the combustion zone; the design of the long-burning boiler provides for operation on natural draft created by a chimney of the required diameter and height. The generated heat heats the water in the jacket of the installation; it begins to flow into the heating system through the upper pipe. The principle of convection works here; the use of a circulation pump is not necessary. The water jacket in a homemade apparatus is located not only around the side walls of the firebox, but also in its top cover.
The grate of a homemade long-burning wood-burning boiler does not perform its usual function; air does not pass through it into the work area. The grate only serves as a support for the fuel mass, and through its cells, ash and ash fall into the lower section, from which they are freely removed with an iron scoop. As the fuel burns in the chamber, the load lowers and you can determine how much firewood is left at the upper end of the pipe. After the process is completed, the door of the ash compartment opens, combustion products are cleaned out of it, the load along with the pipe is raised and fixed in this position. You can make the next download.
Homemade long-burning wood-burning boiler
Pros and cons of wood-burning home heating
The use of solid fuel units is a common way of arranging autonomous heating for private buildings, cottages, garages, as well as industrial facilities.
It is quite possible to construct a wood-burning boiler with your own hands if you understand the operating principles of this equipment, follow the manufacturing technology and at the same time take into account fire safety requirements.
Wood-burning units have the following advantages compared to boilers operating on other types of fuel:
- Wood used for heating is affordable and does not require large energy costs.
- Firewood is an environmentally friendly material that does not cause allergies or other diseases.
- The device is easy to use.
- The room warms up very quickly - after starting the boiler, heat begins to flow into the room immediately.
- Wood-burning equipment is energy independent.
- The appliances can provide hot water at no additional cost. The boiler heats a boiler with liquid, which acts as a water heating radiator.
Wood-burning units have fewer disadvantages:
- The metal body is susceptible to corrosion.
- The equipment requires regular cleaning of ash collected during fuel combustion.
- A single load of fuel is enough for a short time.
Advantages of using a water boiler in a brick stove
One of the key advantages is efficient heat dissipation. It is also an important fact that the pipes can be connected to all rooms from the pipe.
A water-based boiler can be perfectly combined with different heat generators. When using antifreeze, the system will not defrost when the oven is turned off. Among other things, a water boiler in a brick stove can operate both in the presence of central heating and in autonomous mode.
It should also be noted that a water boiler in a brick is very reliable. like the brick oven itself, traditionally considered a reliable heat source. And when such a stove is combined with a water-based boiler, their mutual efficiency becomes many times stronger, and additional heat transfer appears. Together they are able to heat a room of up to one hundred square meters, without forcing you to spend a lot of money on such heating.
For a typical Russian winter, only two fireboxes per day will be enough to create a comfortable temperature in the room. In addition, the temperature can be regulated using modern automated systems.
Water heating with wood
This more complexly organized system is a pyrolysis boiler. consisting of two sections. In the lower one, wood is burned, and in the upper one, the gas generated due to combustion circulates. Thanks to the scheme in which gas does not immediately enter the chimney. its efficiency increases, and longer burning requires less wood.
Around the boiler there are thick pipes through which water flows, heated from it. Keep in mind that only dry firewood is suitable for a boiler of this type, so you should always have a good supply of it at home.
There are also systems that use hot air instead of water for heating. It passes through the circuit and is transmitted into the airspace of the house. The cold air, falling down, again enters the boiler for further heating.
Boilers with a classic combustion chamber
Conventional boilers have a combustion chamber in which heat-resistant steel grates are installed. Fuel is placed on top of them. It burns, ashes and ash fall into the lower compartment of the boiler. The ash pan must be cleaned before each kindling.
A container is placed next to the combustion chamber where water is heated for the water circuit of the heating system. Cooled water flows into the lower part of the container, which gradually rises, warming up.
The boiler has two heat-resistant doors: for loading fuel and an ash pan. The lower chamber allows air to circulate.
Peculiarities
Today, heating boilers have sufficient power to heat rooms for various purposes. They are economical. Their continuous operation time is almost the entire heating season.
These devices can operate on wood, coal, pellets (wood waste compressed and processed into granules), briquettes, peat, and wood gas.
Boiler types
Depending on the type of solid fuel, they are divided into the following types:
- wood-burning (heated not only with wood, but also with pellets);
- universal (they use different types of fuel and their combinations for work);
- gas generator boilers (they have increased efficiency and operate on wood and wood gas).
Models of the latter type are more convenient to use, since soot does not accumulate inside them, and a minimum of ash remains.
There are models of long-burning boilers, dependent on the electrical energy carrier and independent.
Such heating equipment operates on the principle of top combustion (the hearth burns from top to bottom). The combustion chamber, located at the top of the structure, is filled with fuel. The fan forces air through the duct, and the heat generated by combustion is sent to the heat exchanger. The volume of the combustion chamber is about 500 dm3, so such a heating device can operate without interruption for several days.
Advantages
Long-burning designs are heating devices that are very popular among the population. This is explained by their many advantages: not only the use of various types of fuel, but also their long combustion time, as well as the simplicity and environmental safety of their use.
A boiler of this type in its modern variation is a design equipped with automation and a fan to increase the pressure in the system. With a small amount of fuel consumed, such devices can maintain the temperature in large rooms.
The big disadvantage of the design is the high cost, more than 1000 USD. e.
What is pyrolysis combustion
As you know, it is not very convenient to heat a particular room with firewood, since this fuel burns quickly without releasing the required amount of energy. However, if the oxygen content in the firebox is low, the material will be consumed much more slowly. This is precisely what the principle of pyrolysis combustion is based on, due to which significantly less fuel is required and efficiency increases. The main products obtained in this case are coke, ash, and flammable gas, which also releases a large amount of heat.
This means that when constructing a homemade long-burning boiler, you need to take into account the following points:
- Initially, wood burning with a limited supply of oxygen releases flammable gas;
- then the resulting mixture is burned, in turn releasing heat.
Many home-made boilers operate on this principle, but it is important to remember that the equipment must be adjusted so that its operation does not damage the overall system for providing heat to the home
Useful additions
A home-made long-burning boiler assembled at home must be equipped with monitoring devices - a pressure gauge and a thermometer. If you decide to install an automation kit and a blower fan on your unit, then you will need to make a seat for it. The fan is placed in the top cover of the housing; it is better to make the electronic control unit remote by mounting it on the nearest wall inside the furnace room. Temperature and pressure sensors are embedded in the water jacket body. In this case, conventional indicating devices should not be ignored, because they will be able to operate when the power is turned off. Therefore, it is also better to install them, since not every electronic display displays coolant pressure.
After assembly, wood heating boilers must be checked for permeability of welds. Using a compressor, this is easy to do: fill the jacket of the device with water and create an excess pressure of 3 bar in it. Before testing, the seams must be cleaned of slag. Sinks and uncooked areas will make themselves known by leaking. When there is no compressor on the premises, the heating installation will need to be ignited and heated outside until a critical pressure of 3 bar is created in the jacket. Water pressure and temperature can be monitored using a thermometer and pressure gauge.
It is recommended to cover the casing of the water jacket and the inside of all doors of a home-made unit with heat-insulating material. As the latter, asbestos sheets and basalt wool are used, which are not afraid of high temperatures. For external cladding of insulation, you can use thin metal 0.3-0.5 mm with a polymer coating of the desired color.
Installation Tips
Installing a boiler that uses waste oil is practically no different from installing other types of heaters. There is one advantage: thanks to the presence of turbocharging and smokeless combustion of liquid fuel, the chimney does not have to be raised by 6-7 meters. It is enough to remove the chimney head from the wind pressure zone and raise it to a height of 4 m.
Regarding proper installation, we will give the following recommendations:
- The boiler and steel chimneys not protected by insulation are located at a distance of 0.5 m from combustible walls and other elements of a wooden house. The minimum distance from fireproof structures is 100 mm.
- Pass through the outer wall and the entire outer section of the flue with an insulated pipe - a sandwich, otherwise there will be a lot of condensation and soot. The chimney installation technology is described in detail in a separate material.
- Be sure to install a safety group on the heating supply line.
- Organize a good exhaust hood in the furnace to remove odors. Combustion air intake can be provided from the street.
- Equip the supercharger with a speed regulator and the oil line with a valve. This will allow you to control the power of the heat generator manually. Do not confuse the control valve with a regular tap; shut-off valves are installed on pipelines in any case.
- Make a primitive automatic emergency stop - install a thermostat on the supply, turn off the fan and the oil pump in case of overheating of the coolant.
Installation option for a heat generator with a bottom chimney connection
If the waste is supplied by gravity, then for safety reasons it is advisable to install an electric shut-off valve on the fuel line. One subtlety: after an emergency shutdown, the boiler will not start on its own; you will have to light the oil manually or set up automatic ignition.
It is very advisable to insure the operation of the boiler in case of a power outage. A car fan, designed for a voltage of 12 volts, can be powered from a conventional battery, the rest of the equipment - pumps, thermostats - through an uninterruptible power supply unit.
The easiest way to supply used oil to the combustion chamber of the boiler is by gravity - from a container suspended from the wall. But such a system must be constantly monitored, plus as it is emptied, the interval between drops increases and the combustion intensity decreases.
Advantages of double-circuit heating
Double-circuit heating is the type of heating in which water is heated using a boiler specifically for use in the home and for heating the entire room. Thus, the entire need for hot water is provided by one double-circuit boiler. There are other reasons why it is gaining more and more popularity:
- Makes it possible not to depend on utilities and allows you to regulate the heating yourself, thereby creating comfort at home
- Possibility of installation in any part of the house. since no additional exhaust system is required, ventilation is also not required
- Apart from the boiler itself, you will not need anything, because everything necessary for heating and supplying the house with hot water for a long time will already be built in
- Favorable and affordable price
How a wood-burning stove with a water circuit works. Choosing fireplace stoves for a summer residence with a water circuit and a heat exchanger. Brick stove with a water circuit. A stove with a water circuit in development - how to do it yourself.
What determines the operating efficiency of a homemade boiler?
The performance of equipment made by yourself will depend on:
- heat exchanger designs;
- completeness of fuel combustion.
From which it follows that it is necessary to achieve a minimum combustion t°, since the lower it is, the higher the efficiency of the boiler.
The next advantage of the low temperature that a homemade boiler for water heating should produce is its safety and durability.
Making a water circuit
You yourself can easily install and make a water boiler on a ready-made long-burning water stove, and if you don’t have one, then it won’t be too difficult to lay it out of brick yourself. For heating water. You can make a water circuit from old cast iron heating radiators, which you can easily find.
Their capacity is on average one and a half liters. You can connect several of these together and get a heater with a volume of 15 liters at the output, but due to its large dimensions it may not be suitable for use in all rooms. The most acceptable option is a Russian bathhouse.
First, disassemble it yourself. clean and rinse them with hydrochloric acid, or rather its solution. Before installing the entire structure, the gaskets separating the sections should be changed, since initially they are not adapted to high temperature changes. which can reach more than five hundred degrees. Since the old separator will not hold up and the radiator may leak, use impregnated asbestos cord for installation. After this you can start assembling. It must be assembled in such a way that the exit pipe is located above the entire structure, and the entrance pipe is located under it.
Place the circuit ready for use in the chimney as close to the firebox as possible. The hot air coming from there will heat the circuit and, accordingly, the water, making it suitable for heating the house. Subsequently, you will connect the entire water circuit system to the radiators that heat your home
Be sure to first check the entire system for any leaks, paying particular attention to the circuit. which you assembled with your own hands
If you have not found old cast iron batteries for its manufacture, then you can use ordinary pipes for the circuit, but with fairly thick walls.
The water circuit can be applied to absolutely any long-burning stove: from a fireplace to a potbelly stove. You can also make a boiler from fairly thick metal and place it directly under the firebox, which will make it heat up much faster.
Self-production
It is quite difficult to construct a heating boiler with your own hands. The slightest inaccuracy and it will not work correctly, which can lead to tragedy. Therefore, it is necessary to carefully study the technology of their manufacture and carry out all activities very efficiently.
Shaft-type heating devices
You can create a mine or pyrolysis boiler yourself. The first operates not only on wood, but also on coal, peat or sawdust. You can immediately load up to 50 kg of firewood into its chamber.
When the chamber is fully loaded with fuel and high power, such a device will work continuously for up to 5 hours, at the lowest power (15-20 kW) - up to a day. Its efficiency is 75%. The power of such models can be adjusted automatically.
Pyrolysis model
Yellow or colorless wood gas, released under high temperature, is the heat source in the pyrolysis boiler. For such a heating device, you can only use completely dried firewood, otherwise it will not start. The pyrolysis design can also operate on pellets. Their automatic feeding into the furnace (using special augers) will be an additional advantage of the boiler. The operating time of a model of this type when fully loaded is 12 hours.
Disadvantages - high cost (you can reduce it if you make it yourself), energy dependence (the fan runs using electricity), large size. To make such a device you need:
- pipe and sheet of steel 4 mm thick;
- professional pipes, metal rods with a cross-section of 2 cm;
- electrodes;
- fan;
- fire bricks;
- automatic temperature controller;
- fasteners.
They first draw up a diagram of the future boiler with all the calculations. The most successful design of a homemade boiler in this regard, developed by engineer Belyaev, is taken as a basis. Adjustments are made to it according to the wishes of the home owner. For example, heating can be made more efficient by increasing the volume of the heat exchanger jacket.
Homemade pyrolysis devices must be installed on fireclay brick platforms specially equipped for them. After this, they are connected to the water circuit.
During the first test switch-on, they find out whether there were any errors in the boiler design. If everything was done correctly, the device can quickly switch to gas generator mode. The room will become much warmer within half an hour.
Tools and materials
A wood heating device is the safest design. Its autonomy, ease of operation, minimal risk of explosion, and the possibility of self-production are its main advantages. Its disadvantage is the regularity of adding fuel.
Homemade wood-burning boiler models can be made from the following materials and parts:
- metal barrel (volume – 200 l);
- steel sheet 3-5 mm thick (to create a firebox);
- metal pipe with a diameter of 20 mm and a wall thickness of 3 mm;
- L-shaped pipe (diameter – 20 mm);
- grate;
- doors for the vent and firebox.
Homemade models of wood-burning boilers are made using gas welding equipment and an angle grinder.
Sequence of work
Before starting work, you must carefully consider the design of the device, purchase all the necessary materials and tools.
Cut 3 circles (diameter of each 57 cm): this is the bottom, the top cover and the partition between the ash pit and the firebox. Make a hole with a diameter of 20 mm in two of them.
A strip 400 mm wide and 3600 mm long was cut from a sheet of steel, holes were cut in it for the firebox door, and below it for the ash pan. Weld the sheet together into a circle.
Weld a circle with a hole on top and without one on the bottom. Install a partition with a grate between them.
Weld the pipe and the barrel together according to the “one inside the other” principle. Install a firebox with a blower underneath. Connect all elements by welding.
Attach an L-shaped piece of pipe to the top of the barrel: it will connect the heating container and the chimney. When water heats up in a barrel, it forms steam, which will freely escape into the chimney, thereby preventing the pressure in the boiler from increasing.
Install pipes at the top and bottom for cold water inlet and hot water outlet.
Hang the doors on the firebox and vent.
Install the structure on a foundation made of refractory bricks.
Such a device heats using firewood, pellets or peat, tightly packed inside the firebox.
Even the simplest model of a wood-burning boiler requires care and attention when making it yourself
