Coal boilers. Overview of solid fuel boilers with automatic fuel supply

At the moment, an automatic coal boiler has already ceased to be a rarity, and has earned a reputation as an autonomous and reliable heating equipment that can compete with pellet stations.

How automated coal-fired boilers work

The principle of operation is as follows:


The microprocessor controller is the "heart and brain" of a coal-fired boiler. But, uninterrupted operation depends on several other elements of the system. An important role is played by a coal burner and a bunker - a batcher for coal.

If the technical characteristics of the automatic coal-fired boiler are selected correctly, there will be no soot residues at the outlet of the chimney, and the smoke temperature will remain within 150 ° C.

The principle of operation of a coal burner

The main tasks of the burner are as follows:

1. Provide optimal conditions for complete combustion of fuel with a minimum amount of underburning.
2. Guarantee the maintenance of the flame of fire, for maximum heat transfer.
3. Prevent excessive coal consumption by optimizing fuel rationing.

Manufacturers use two types of burners, depending on which coal is used for auto-feed boilers:

When choosing a household automatic coal-fired boiler, they take into account the features of the future operation of the device, in particular, the type and size of the fuel fraction. The type of burner depends on this parameter.

To automate the supply of fuel to the coal boiler, a microprocessor controller is used, which is practically a mini computer. An optical sensor is installed on the burner, which monitors the presence of a flame. When attenuated, a signal is given to re-ignite.

The controller is connected to several room thermostats for automatic control of the boiler. The heating temperature of the coolant varies, depending on the readings of the sensors. Modern models use weather-dependent automation that allows you to change the boiler settings, taking into account the ambient temperature.

Coal enters the burner in precisely measured portions, after which it burns out. A signal is sent from the burner to the controller, which starts the movement of the fuel conveyor. A new portion of coal enters the burner, the fans turn on. The high efficiency of the boiler, which is 87%, depends on the coherence of actions.

The minimum technical requirements for the burner control system are: the accuracy of feeding portions of coal, the possibility of automatic control of the combustion process. The modulation of the device should be between 30-100%.

The device of the bunker-dispenser for coal

The loading hopper is designed as a metal storage with a screw conveyor installed at the bottom. The design contains several important components that prevent jamming of coal in the auger and caking of fuel.

To automate the supply of coal to the boiler, the following important components are used:

• Automatic coal crusher - burner and screw conveyor, designed for the use of fuel of a certain fraction (up to 25 mm). The rock is poured into a special successor, with an installed coal crusher. After grinding, the fuel enters the moving conveyor.
• Coal ripper - a special device is installed in the bunker to prevent the stored coal from churning into lumps, which ensures a uniform supply of the fraction to the auger and prevents it from jamming.
• Feed gear motor - in motion, the conveyor drives the auger electric drive. Depending on the model, the power consumption required for operation is 130-180 watts. The electric drive is connected to the automation, turned on and off by a signal from the controller.
• Fuel storage - solid fuel automatic coal-fired boilers with a bunker, there are several types. The former are connected to a mechanized, stand-alone storage facility. The advantage of this solution is the almost complete absence of time restrictions in the autonomous operation of heating equipment.
  The storage capacity is sufficient for the boiler to work without stopping during the entire heating season. Automatic coal-fired boilers with a built-in bunker do not require the modification of a separate room for mechanized storage. The capacity of the fuel tank in the bunker coal boiler is enough for 3-7 days.
• Portion drum - auger transmission does not feed coal directly to the burner, as is the case with. To begin with, a portion of fuel is loaded into a special portion drum. After giving a signal from the controller, the drum starts to spin. A portion of the fuel is poured onto the burner in an even thin layer. After the coal burns out, the automation gives a second signal and the process repeats.

Which coal is suitable for automatic boilers

The main requirements for fuel quality for all hot water solid fuel heating boilers with a fully automated coal supply system are:

1. Fuel grade "eco-pea".
2. The recommended fraction size is from 5 to 25 mm.
3. The amount of fine particles is not more than 60%.

Optimally corresponds to the requirements described above, packing coal in bags. But if the purchase of ready-made fractional fuel is not economically feasible, it is allowed to use special crushers.

By passing coal through a crushing device, you can get a large amount of coal, strictly defined fraction. The disadvantage of the solution is a large amount of dust and small particles, fines. The resulting composition is burned exclusively on an AKM type burner.

How to choose an automatic coal fired boiler

The selection of a heating boiler is carried out based on the following thermal parameters:

• Degree of automation - modern bunker automatic coal-fired heating boilers, equipped with a microprocessor controller. At the request of the buyer, the heating equipment is equipped with a self-cleaning system and remote control.
  After installing the GSM module, the operation of the boiler is controlled using any mobile device. The new generation controller is able to automatically support the operation of several heating circuits: radiator heating and "warm" floors.
• Fuel storage capacity - usually, the bunker is calculated in such a way as to ensure autonomous operation of the boiler for 3-7 days.
• Productivity - the calculation is performed according to the formula 1 kW = 10 m².

Additionally, the degree of insulation of the device is taken into account. When using coal in a boiler room, there is a high probability of accumulation of combustible dust. Therefore, the control unit must have a degree of protection of at least IP 26.

Leading manufacturers of coal bunker boilers

Russian-made boilers remain the cheapest. At the same time, the models have high build quality, reliability and long service life.

European boilers are offered in premium class. Models are highly automated and functional.

The most popular are:

• German boilers - Roda,.
• Czech boilers -.
• Turkish models - Termodinamik, Emtas.
• Polish boilers - Stalmark,.

It is worth paying attention to the boilers ALTEP, TIS EKO, KAZ Kordi.

Asian solid fuel boilers are presented in a small range of products. Attention deserves the Kentatsu models, which differ in functionality, but are inferior in terms of thermal performance and reliability to Russian and European counterparts.

The cost of automatic boilers on coal

European counterparts are more expensive, about 2-3 times more. Boilers manufactured by Buderus and Roda will cost 350-500 thousand rubles. The piping of heating equipment costs approximately 5-10% of the cost of the station.

Opinions on coal-fired boilers with automatic fuel supply

Despite many positive aspects: long battery life, high degree of safety, efficiency and reliability, boilers have several real disadvantages:

• Dependence on electricity - the operation of the boiler without electricity is impossible. After the power is turned off, the screw transmission stops, the system of forced injection and removal of combustion products. To ensure the operation of the boiler, the connection to the mains is carried out through and.
• Dust deposition - a coal firebox has one significant drawback. In the process of combustion and fuel supply, a large amount of fine dust accumulates. Under a number of circumstances, small particles, reaching a certain concentration, can cause an explosion. Dust control when loading the bunker with coal, includes the installation of special dust collectors. Regular wet cleaning is also required.

Coal boilers are classified as solid fuel. With their help, you can heat the house with coal or wood. At the same time, modern models of devices can work in automatic mode. The automatic coal-fired boiler independently controls the operation process and ensures the efficiency of fuel combustion. A conventional coal-fired boiler works without automation and gives less efficiency. How are coal-fired boilers arranged, and what additional devices help them to work in automatic mode?

A coal stove or boiler is designed to produce heat by burning solid fuel. This heat is spent on heating the coolant (water or other liquid antifreeze), which then enters the heating pipes. Charcoal heating has the highest heat capacity among other solid energy carriers (wood, pellets). It is used for seasonal heating of private houses, as well as for the operation of boiler houses that heat several rooms. Modern for heating a residential area more often uses natural gas. Coal heating is popular in small boiler houses that heat several houses, garages, workshops or other premises.

Capable of working on coal

Note: When coal is burned, carbon monoxide gases are formed, the temperature of which varies around 1300ºC. The efficiency (COP) of a classic coal-fired boiler is only 70%. A significant part of the thermal energy is lost due to incomplete combustion of gases. In improved models of boilers for heating with coal, the efficiency of work is higher - 80 and 90%. They burn fuel more efficiently with less smoke and soot. Such boilers are called pyrolysis.

Pyrolysis boilers

The pyrolysis unit has two combustion chambers. In the first, coal burns and carbon monoxide gases are formed, and in the second, the gases themselves burn out (they “burn out”, that is, the unburned particles contained in them are oxidized and emit heat). In this case, no smoke is generated at the outlet of the device. Thus, the efficiency of heating with coal increases, the completeness of its combustion is ensured and its consumption decreases (and hence the cost of heating). In pyrolysis boilers, the efficiency of energy consumption is 90-92%. At the same time, they are demanding on the moisture content of the fuel (up to 30%).

Long burning boilers

In addition to pyrolysis devices, coal is used for heating. Their work efficiency is less than pyrolysis (80-85%), but better than classic coal-fired boilers. In long-burning boilers, air is supplied exactly to the flame zone by a special blower. The intensity of fuel combustion and the temperature of the coolant depend on the amount of air, its temperature and feed rate.

Long-burning devices are demanding on the quality of the fuel (coal must be dry). Otherwise, soot accumulates on the pipes, which reduces efficiency and disables automation.

Conventional boilers for heating a house with coal have a minimum of automatic controllers. For their work, a separate room is needed - a coal boiler room. Pyrolysis units and devices for long burning are equipped with automation. It provides control of work and the absence of carbon monoxide, which allows them to be installed inside domestic premises. What ensures the uninterrupted operation of heating units?

About solid fuel boilers for long burning

Automatic boilers: device and advantages

Note: An automatic coal boiler differs from the usual one by the presence of additional appliances. Automatic controllers free a person from the need to control, as well as increase efficiency and reduce coal consumption and the amount of ash generated.

What does automation do?

• Control and supply of coal to the furnace. The design of the unit has a filling hopper with an auger (or drum) for automatic fuel supply. At the same time, it is enough for a person to replenish the supply of coal in the bunker every few days (from 3 to 10).
• Control and supply of air to the combustion zone. Controlled supply and preheating of the air mixture also ensures the uniformity of fuel combustion and the efficiency of the device. The efficiency of fuel combustion in an automatic unit is 90% (for comparison, a stationary coal stove has an efficiency of 60%, a classic boiler - 70%).
• Automatic dumping of ash by movable grates.

Autonomous mode of operation of the unit is determined by the specified parameters. The owner of the house sets the temperature value for heating the liquid and the temperature inside the room. In accordance with them, automation activates combustion or maintains a smoldering mode (up to 5 days). Continuity of combustion allows ignition to be done once per heating season.

How does automation work? Based on the analysis of the temperature inside the boiler and in the coolant tank, the pressure values, commands are sent to the air supply controller. An increase in the rate of its supply or its decrease leads to an increase in combustion or its weakening. Which in turn regulates the heating temperature of the liquid inside the heat exchanger.

Automatic controllers run on electrical energy. Therefore, boilers with automation are called volatile. They require a source of electricity (socket, battery).

Model range of automatic coal boilers Defro

Devices for heating with coal are more expensive than wood-burning ones by 20-40% of their cost. But the use of automation can reduce heating costs. Customer reviews confirm that coal consumption savings in some automatic boilers reach 50%. This makes coal heating profitable for individual houses, workshops, workshops and other isolated premises.

Boiler device

Boilers for heating with coal have the following device:

• Coal furnace. At the bottom of the firebox is a grate. In automatic boilers, the rotation of the grate helps to dump the ash into the ash box (located below the combustion chamber). The size of the furnace depends on the availability of the bunker and automatic fuel supply. If there is such a supply, the size of the furnace may be small. If there is no supply, then the firebox should be large in order to accommodate as much coal as possible and increase its burning time.

• A heat exchanger is a container in which water circulates. Depending on the design of the heat exchange tank, there are boilers with a water jacket and tubular. In the "water jacket" design, the water washes the combustion chamber. This is how most of the long-burning boilers are arranged. At the same time, the shirt itself is located along the entire firebox and descends to the ash compartment. In a tubular design, water tanks have the form of pipes that pass through the top of the firebox in a horizontal, vertical or inclined position.

• Block of automation and security.

Coal and wood boiler: what is the difference?

The technical passport of solid fuel boilers indicates that they can run on any type of solid fuel (wood, coal, pellets, briquettes). However, there are some differences between wood and charcoal devices. Let's specify them:

• The size of the heat exchanger capacity is determined by the value of 5-25% of the capacity of the entire heating system. That is, if you have about 500 liters circulating in the heating pipes (this is about 30 batteries, each of which contains 15 liters), then the capacity of the heating boiler should be from 23 to 120 liters. With a more accurate choice of the size of the tank, the type of fuel on which the unit will operate is taken into account. The greater the heat capacity of the energy carrier, the greater should be the volume of liquid that is heated inside the boiler. When heating with coal, the volume of the water tank is larger than when heating with wood. It approaches higher values ​​(in the case of the given example, to 120 liters). The small capacity of the boiler is suitable for wood heating.

• The combustion of coal is often accompanied by the formation of a large amount of carbon monoxide, the ejection of unburned particles into the pipe, their deposition on the walls and pipes in the form of soot. Unlike coal, wood produces cleaner gases and produces less soot. Therefore, for safe and efficient heating with coal, it is better to use pyrolysis coal stoves or long-term upper combustion boilers.

Automatic coal-fired boilers can reduce the cost of winter heating at home and provide autonomous heating. At the same time, automatic boilers give out a stable temperature, do not require daily monitoring and waste of time.

About heating using a Buderus boiler

1. Automatic boiler "Yamal" long burning
2. Coal boiler "Barin" with automatic feed
3. Solid propellant automatic boiler "Carborobot"

The problem of organizing the automatic supply of solid fuel has always worried the developers of solid fuel boilers. If in the case of firewood it is quite problematic to organize it, then when using coal and pellets, the situation looks more real. Today in our review we will look at the most popular automatic coal-fired boilers, and how they implement the mechanism for delivering fuel to the combustion zone.

Automatic feeding of pellets is most often done using a soft or hard auger. It is possible to deliver coal to the furnace with a screw conveyor only if its fractions are sufficiently small and homogeneous, and most often this is not the case. Today we will consider several coal-fired boilers, in which the mechanism for automatically supplying fuel from the bunker to the combustion chamber is implemented in different ways.

Everyone who has heated their home with coal knows about the main problem of this fuel, which prevents it from being automatically fed into a solid fuel boiler. Usually, its fractions differ in size, hence the automation of feeding in the form in which it is implemented, for example, in pellet boilers, becomes impossible. The developers of the Yamal automatic coal boiler solved this problem by applying a completely new feeding method that can work effectively even with fractions of different sizes.

Photo 1: Household coal boiler "Yamal" with automatic feed

The essence of this method, like all ingenious, is extremely simple. A conveyor is installed inside the hopper with inclined walls, picking up pieces of coal and lifting them higher and higher. At the highest point there is a toothed crusher, which passes fractions of suitable size, and those that are larger either split on its teeth or fall back into the bunker. As you can see, the mechanism does not contain complex structures, and even if it fails, anyone can set it up with their own hands.

The operation of the Yamal boiler is fully automated. Fuel supply, ignition, slag discharge, power adjustment - all these processes occur automatically under the supervision of an electronic control unit. When the fuel bunker is completely filled and the diesel burner is filled, the coal-fired boiler is able to independently heat the room for 20 days.

The manufacturer produces three Yamal models of different capacities. Below are their main technical data:

Taking into account the fact that pellets have not yet become widespread in our country, a robotic coal heater is perhaps the only affordable way to organize an autonomous solid fuel heating system in our country. We talked in more detail about the Yamal automatic long-burning coal boiler in one of our previous reviews.

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In the solid fuel boiler "Barin" automatic feed is organized in a slightly different way. Here the bunker is located above the boiler, and the coal under the influence of gravity descends into the combustion chamber. Its caking on the walls of the fuel tank is prevented by a system of collapsers.

Having passed the shaft connecting the furnace and the bunker, surrounded by a water jacket, the coal enters the water-filled grate, where it is burned. The design of the shaft makes it possible to pre-dry the fuel, for its more efficient combustion in the furnace of the boiler "Barin". Hollow grates are filled with coolant both to increase the heat removal area and to prevent coal from burning to their surface. Directly below them is the first compartment of the ash pan, which accumulates mainly fine ash.

Burnt-out coal collides into the second compartment of the ash pan with the help of a screw mechanism. In the path of flue gases, still containing unburned fuel particles, there is a secondary afterburner chamber lined with fireclay bricks. Here, high-temperature afterburning of gases takes place, after which they, having passed through the system of a tubular heat exchanger, are discharged into the environment through a chimney.

Management and control of the boiler is carried out by an automatic control system. It maintains the combustion process at the required level, controls temperature and pressure, and also performs many other functions. The task of the owner is to set the necessary operating parameters once, and then only add coal to the bunker and periodically clean the ash pans.

The table below shows some of the technical characteristics of the automatic boiler "Barin":

You can learn more about the device, operation, advantages and disadvantages of an automatic heating boiler at the Barin coal from a special review on our website kotlydlyadoma.ru dedicated to this model.

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Coal boilers "Carborobot" are produced in two modifications: Classic and Classic Bio. The first one is intended for combustion exclusively of brown coal, and in the second it is also possible to use various biomass, such as wood chips, pellets, husks.

Structurally, this unit consists of a main body with a furnace and a heat exchanger, on top of which a fuel bunker is fixed. Inside, the steel case is divided into two parts by a partition, in which there is a hole through which hot gases from the front part enter into the back.

The first compartment of the Carbobot boiler is located directly under the bunker and is a combustion chamber and a large ash pan. The process of burning fuel takes place on a rotating cast iron drum, and the resulting ash falls into the ash box.

In the second compartment, located behind the first, there is a tubular heat exchanger. Passing through it, flue gases give up their energy to the coolant and then are discharged into the atmosphere.

The entire process of the boiler is controlled by electronics through several motors. At her command, the stepper motor turns the grate drum, dumping burnt fuel into the ash pan and supplying a new portion from the bunker. The smoke exhauster motor creates forced draft, directing hot gases into the chimney through a heat exchanger.

In one of the recent reviews on our website, we considered the Russian Prometheus coal-fired boiler with automatic feed, which, like two drops of water, is similar to the Carborobot both internally and externally.

The table below shows the technical characteristics of household boilers "Carbobot" Classic:

In addition to the above, watch a short video about the Carbobot coal boiler:

Back to the table of contents Conclusion

After analyzing several models of automatic boilers, we can draw some conclusions. Most models are demanding on the size of coal fractions and are able to work autonomously for a long time only when loaded with fuel of the required quality. Therefore, if you have a reliable supplier of fine coal, you can safely buy a coal machine for heating your home.

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Types and features of automatic solid fuel boilers

The absence of a gas pipe in a suburban village is the reason that the heating system of houses will be based on other types of fuel: electricity, solid fuel or liquid. Traditionally, consumers choose solid fuel boilers, considering them more reliable, and the fuel used in them is available and cheap. True, such boilers have two drawbacks: you have to constantly monitor the loading of the furnace and turn off the unit if the house is left for several days. Both problems are quite serious, but they can be solved by using automatic solid fuel boilers.

The one who invented the design of this unit, himself, for sure, suffered for a long time, using a solid fuel boiler in his own house. The novelty caught on the market immediately. First, the economic side of the matter was fully respected. Secondly, this type of boilers works very efficiently. Thirdly, the issue of manual labor has finally been resolved.

A variety of automatic solid fuel boilers

• Traditional type. These are conventional solid fuel boilers, the automation of which is manually adjusted. The air supply to the combustion chamber is regulated by a gate valve, the same can be said for the fuel supply, the temperature regime is set manually. These boilers have a big plus - they can work on any type of solid fuel.
• Combined option. In this design, various devices are installed that support the combustion mode of a particular type of fuel. In some models, each type of fuel has its own combustion chamber; in others, you will have to modify the furnace. For example, installing a burner.
• Pyrolysis heaters are a unique design that uses the technology of extracting thermal energy not only from fuel combustion, but also from the exhaust gas during combustion. In fact, these are automatic solid fuel boilers of long burning, where solid fuel does not burn, but smolders. These are by far the most expensive, but very popular heating devices. They have a fairly high efficiency - 90%. The only thing that sometimes repels consumers is the volatility of the boiler. But its functionality is at the highest level, all processes are performed automatically. It can be said that pyrolysis boilers are a modern approach to solving problems related to heating a private house by automating the control and regulation of combustion processes.

Monoboiler with built-in bunker

Attention! The functioning of the pyrolysis boiler in the established mode can vary from one day to a whole month. But in this case, the setting of a certain mode does not depend on the design of the boiler itself and not on its functions, but on the volume of the bunker where solid fuel is poured.

Currently, in specialized stores, consumers can choose units that are different in power. This figure varies between 10-250 kW. The same can be said about diversity and fuel. Here are pellets, and coal granulate of various sizes, and sawdust, and a splinter, and so on.

The principle of operation of the boiler

An automatic solid fuel boiler is still the same ordinary boiler with a small addition in the form of a bunker, which is a kind of warehouse from where fuel is automatically supplied to the furnace of the heating unit. Therefore, specialists pay special attention to the installation process of all parts. Full and exact compliance is required, due to the instructions. If the installation process is carried out at the highest level, then we can talk about high-quality long-term operation of an automatic solid fuel boiler. Principle of operation

It is clear and without words that only granular types of solid fuel can be fed into the combustion chamber through the bunker. It will obviously be impossible to use firewood here. But that's not a problem either. Wood pellets are inexpensive, you can find them today in almost all stores. Although many models of automatic solid fuel boilers can use small wood waste in the form of wood chips or sawdust. But be careful, the product passport indicates whether they can be used or not. Because manufacturers put forward their own special requirements for each model.

Why are the requirements different? The thing is that the size of the supplied fuel particles, as well as their technical characteristics (humidity, density), play a special role. Some automatic models can easily accept even the smallest pieces of wood, in some medium sizes can be used. This is an important component of the efficient and long-term operation of boilers.

Fuel is supplied to the combustion chamber by means of an auger, which is rotated by a small electric motor. The bunker can be located as a stand-alone unit, or be integrated in the same building with the boiler. The most common unit at present is a solid fuel pellet boiler.

What are pellets

These are fuel pellets that are made from waste wood, peat, agricultural products (straw, corn cobs, chicken manure, etc.). These are the crushed materials described above, which are pressed into cylindrical granules of a certain size. The size of the pellets determines the possibility of their passage through the auger hole into the boiler furnace.

Pellets

By the way, for information: to make one ton of granular pellets, it is necessary to process from 2.3 to 2.6 m³ of wood. Plus, the production process itself requires thermal energy, which is released by burning another cubic meter of sawdust. Pellets are packaged in paper bags, the volume of bags can vary from 2 to 20 kg.

How are pellets different from regular firewood? Their humidity is 8-12%, for firewood it is at least 15%. The density is one and a half times higher. All this ensures high heat transfer of the fuel, even if it does not burn, but smolders.

Solid fuel boiler device

Automation

In automatic solid fuel boilers, the automation system performs several very important functions:

• The temperature is set and controlled regardless of the weather conditions outside.
• Ignition in most models is also carried out automatically.
• Supply of pellets depending on the set operating mode of the boiler.

But the cleaning and cleaning of the combustion chamber will have to be done manually. It is not difficult, especially since the process itself is carried out once a week.

pyrolysis boiler

Currently, manufacturers of automatic solid fuel boilers offer different types of automatic systems that can:

• Manage all processes remotely.
• Set the temperature regime for several days, weekly, hourly, and so on. The smaller the mode setting step, the more modern the automation is used in the boiler, the more expensive the unit itself.

Requirements for the organization of the operation of solid fuel boilers

• A separate room for the boiler room, which meets all fire safety requirements.
• Well-functioning ventilation system.
• The boiler is installed on a solid foundation (foundation or pedestal).
• The surrounding structures of the solid fuel boiler must be built from non-combustible materials or be sheathed with them.
• Correctly install the chimney under certain standards that require the model of the unit.

Correct installation

By the way, the chimney must be given special attention. It is his competently carried out installation that guarantees that the automatic solid fuel boiler will work efficiently, correctly and for a long time. That's why:

1. The chimney pipe must be made of a heat-resistant material that could withstand metal corrosion processes.
2. Optimal dimensions: diameter - 180 mm, length 4.0 m.
3. The chimney must be insulated.
4. Mandatory device of revision holes. The thing is that when solid fuels are burned on the chimney, soot is deposited in large quantities, which reduces the cross section of the pipe. And this is the reason for the decrease in traction. So you have to manually clean the chimney periodically. This process is unpleasant, but very necessary.

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Types and features of automation for solid fuel boilers

It is impossible to imagine any heating equipment related to the heating of residential premises without automation. The equipment of heating devices with certain mechanisms, devices and devices not only increases the efficiency of the boiler equipment, but also ensures the safety of the operation of boiler equipment. A solid fuel heating boiler, although it is a high-tech device today, like other types of heating devices, needs to be equipped with automation.

Compared to classic solid fuel boilers, heating units manufactured today are the most automated devices. Automatic solid fuel boilers cope with their tasks without human intervention. During the periods between fuel fillings, the entire system is completely autonomous and independent, giving the output the optimal temperature regime in the house and hot water supply. Let us consider in more detail what automation is for heating solid fuel units.

The main functions that are assigned to automation

Before installing a solid fuel boiler, you should carefully study the principle of its operation and control mechanisms. The study of the processes of the working cycle of the heating device will allow you to understand how the devices and mechanisms that control the heating system work. What is automation for solid fuel boilers today, and what are its main functions.

The following functional tasks are assigned to automation:

• ensuring optimal temperature conditions in the heating circuit;
• performance of a controlling function for the operation of the pump and the three-way valve in the mixing circuit;
• ensuring control over the operation of the circulation pump on the main heating circuit;
• temperature control of water heating in the DHW system;
• provide switching on/off of the three-way valve;
• automation of boiler equipment is a set of equipment together with a room thermostat.

The diagram shows the usual piping of an autonomous heating system with installed automation.

Automation of many processes during the operation of solid fuel heaters makes it possible to achieve significant savings in the fuel resource and free the inhabitants of the house from the function of a stoker. Today, automation is a set of complex and energy-intensive devices, each of which solves a certain range of tasks and issues.

An automatic boiler is a unit that is able to work completely and completely offline, starting with fuel loading and ending with adjusting the heating temperature.

For reference: All processes, starting with fuel filling, ignition and control over turning on and off, are done automatically. without your participation. The presence of sensors and controllers allows the system itself to respond to a changing situation. Based on the parameters you set, the boiler operates in the established modes.

What are the types of automation

The capabilities of modern electronic devices included in the set of equipment for controlling the operation of the heater are quite wide, allowing you to configure the devices in accordance with your own priorities and desires. In most cases, the set of modern complex heating devices includes:

• a computer that provides control of the heating device;
• fan or air turbine.

Today it is possible to equip conventional semi-automatic solid fuel units of almost any kind with an automatic control unit of the Comfort Eco type. A semi-automatic solid fuel boiler equipped with such a kit can already perform most of the processes on its own. Sensors regulate the heating temperature of the coolant, the state of traction. All information is displayed on the screen. An ordinary pyrolysis boiler or a long-burning unit with automatic equipment becomes an order of magnitude more convenient to use and safer.

If everything is more or less clear with electronics, then the mechanical part should be dealt with in more detail. There is a classification of automation in terms of autonomy. In this case, it is customary to distinguish:

• automation, volatile - powered by electricity;
• automation, non-volatile, which does not require connection to the mains.

In the first case, the operability of the main devices is feasible only when the devices are connected to the power supply. To improve the safety of such devices, the autonomous heating system is equipped with a UPS. The first option looks preferable, since network-operated automation has more functionality.

The second case is focused on greater autonomy. Such options are very convenient in situations where power outages are frequent, and the heating device is configured to work independently without unnecessary electronics.

Important! If your boiler is set up properly and works autonomously, without additional means of monitoring and recording the temperature, you need to visit the boiler room more often.

Advantages of boiler equipment on which automation is installed

The first thing that draws the attention of any owner of heating equipment is the ability of the heating device to independently regulate the heating temperature of the main heating circuit. Previously, everything was done by hand. He pushed the damper, the temperature began to fall and vice versa, he opened the blower, the boiler began to work more intensively, the temperature rises.

Modern automatic solid fuel boilers of long burning are able to work without human intervention for a long time (up to 48 hours), independently regulating all processes. It is only important for you to set the required temperature regime inside the dwelling. Thermal sensors respond to changes in room temperature by sending a signal to the central control panel. Already from there, a command is sent to turn on special pressurization fans that provide the combustion process with air.

The next important advantage that automation gives to solid fuel boilers is the independence of the heater in operation. Now there is no need to turn off the boiler when leaving and wait for it to cool down completely, while the heating system must be drained so that it does not defrost.

Today the situation has changed radically. With the help of automation, you can adjust the operation of the heating unit in the minimum (support) mode. In other words: You set your boiler to a specific temperature. While you are not at home, the boiler works in order to maintain minimum temperature indicators in the system. In order for the heater to start at maximum speed, it is enough to set the timer. You arrive, and your house is warm.

In the case of arson of solid fuel, the situation is generally simplified. A person is absolutely not needed for this. At the set time, the electric ignition will work and the boiler will start working.

The main emphasis in the latest models is on achieving the safest operating mode. Solid fuel units equipped with automatic control devices are able to regularly carry out self-diagnostics, detecting malfunctions in the operation of one or another element. For a solid fuel boiler, fast response remains important. The faster the devices and the system react to an emergency, an increase in pressure in the system, a sharp jump in temperature, the faster the system will stop automatically.

Solid fuel boilers with automatic feed

It is especially worth dwelling on the category of solid fuel heating devices that are equipped with devices and mechanisms that facilitate the work of the stoker. We are talking about such a type of boiler equipment as a solid fuel boiler equipped with an automatic fuel supply mechanism. A number of current heating units are equipped with special devices, with the help of which fuel is constantly loaded into the combustion chamber. Such devices are called pellet, because pellets go into the furnace - small, easily combustible granules made on the basis of wood waste.

Boilers with automatic fuel supply are considered one of the most efficient. The efficiency in such a device reaches 80-85%, due to the most complete combustion of fuel and automation of the process itself. Such equipment provides during operation the necessary comfort, cleanliness and coziness in the house. Solid fuel is carefully poured into the hopper and from there it is fed by a screw mechanism into the combustion chamber.

Note: in pellet aggregates, automation regulates not only the intensity of air supply to the burner, but also the amount of pellets entering the furnace. There are pellets on the burner, the unit is running, there are no pellets, the heater is turned off.

Solid fuel heating boilers, in addition to automatic fuel supply, are also equipped with a device that allows you to clean the ash pan without human hands.

Installation of automation

If you can install the boiler and lay the pipeline of the autonomous heating system yourself, then when equipping the heating device with control and automation devices, you will need the services of a specialist. Automation for solid fuel boilers requires careful and precise tuning. The process of installing and directly configuring the equipment is complex and painstaking. Therefore, saving in this case is not worth it.

The first thing specialists pay attention to when starting the installation of equipment is the installation of a ventilation system, which is based on a fan. The equipment is installed at the bottom of the heating device, in the place where the conventional damper is located. The fan is fastened firmly enough that it would not be torn off during operation. The next step is to install the controller. For a wood-fired boiler, such a device will be a real find. Typically, the controller is a heating unit control unit, which automatically contains various operation algorithms. The main thing here is to correctly place the sensors and make adjustments. After setting the system is connected to the power supply, the first test run of the heater is made.

In custody

Recently, more and more, the market for solid fuel boiler equipment has been replenished with advanced devices and control systems. Not only foreign models of boilers, but also most of the domestic manufacturers today rely on equipping heating devices with automation.

The control unit, which has a liquid crystal display, does an excellent job with the tasks assigned to it. Now heating devices are not only easy to control, they practically do not need to be controlled. Fine tuning of all elements of the control system will allow the heating equipment to respond with high accuracy to the slightest changes in temperature. Now your unit is not afraid of overheating or defrosting.

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Coal-fired boilers Defro long burning: overview of characteristics

Each owner of a solid fuel heater is always looking for an opportunity to save on fuel and automate its loading. Solid fuel boilers are usually very demanding on the quality and size of raw materials, and you have to load it manually several times a day. Taking into account all these shortcomings, designers from Poland designed a model of a heating boiler that runs on coal of the lowest grade, which is also fed into the furnace automatically. In this article, we will look at Defro automatic boilers, their advantages, characteristics and design features.

Defro has been manufacturing solid fuel heating boilers for almost 50 years. Today it is the leader in the production of heating equipment in Poland, occupying 70% of the market. In its lineup there are both classic boilers without automation, and fully automatic complexes that can function autonomously for a long time. In our review, we will not touch on traditional devices, but will consider only models with automatic feed.

The main problem with heating with wood or coal is that it is necessary to constantly throw new portions of fuel into the boiler as it burns out. It is not possible to organize an automatic supply of firewood due to their different caliber and large sizes. With coal, the situation seems simpler, but the same heterogeneity of coal fractions prevents the organization of autonomous work.

The only possible option is the use of fine-grained coal "peas" or low-quality coal fines. It was this type of fuel that Defro focused on in the production of coal-fired boilers.

To supply coal from the bunker to the furnace, a special piston mechanism was developed that pushes it through the connecting channel. After passing through the supply system, a portion of the fuel falls on a heat-resistant steel plate, over the entire area of ​​​​which there are holes for air supply. The air mixture is forced under the plate by a fan located at the rear of the boiler.

In the upper part of the combustion chamber there is a ceramic plate that provides afterburning of gases. After that, having passed a complex labyrinth of a steel heat exchanger and giving maximum energy to the coolant, the exhaust gases are discharged into the chimney through the chimney pipe.

Defro hot water boilers can operate in the following modes:

All processes occurring in the boiler are controlled by the controller. It regulates power, fuel supply, water temperature and pressure in the heating circuit, as well as many other parameters.

In this case, the controller assumes only the task of monitoring the intensity of combustion and the state of the heating system. Fuel supply is carried out manually. In this case, it is possible to use different-sized coal or firewood.

The controller is completely disabled. The air supply is manually controlled by a mechanical damper. The owner must also control other parameters of the heating system. Typically, this mode is used only during a short-term power failure.

Technical characteristics of automatic heating boilers Defro AKM:

As you can see, the Defro hot water boiler is not just a solid fuel heater, but an intelligent system that can function almost autonomously. It already bears little resemblance to a traditional heating device, such as, for example, a Dakon coal-fired domestic heating boiler.

In addition to the flagship Defro AKM line, several varieties are also available:

It consists of two combustion chambers located one above the other and separated by water-filled grates. The upper chamber is used for burning coal or firewood in manual mode, and the lower chamber is equipped with a burner for automatic operation.

A series of low-power automatic coal-fired boilers. Available in 5 sizes, with power from 11 to 27 kW. Structurally, they consist of two chambers: for automatic and manual work.

Universal model with a new burner. In addition to coal, it is also able to work effectively on pellets, husks and other woodworking and agricultural waste.

When designing the Defro AKM hot water boiler, many innovative solutions were applied. Let's look at their advantages over classic direct combustion boilers:

• A heat exchanger of complex shape made of high-quality heat-resistant steel provides maximum heat removal;
• The use of high-tech devices at the stage of combustion and heat removal makes it possible to achieve an efficiency of up to 87%;
• Efficient emergency extinguishing system that does not require power supply;
• The large combustion chamber is equipped with cast-iron grates for manual operation, for example, when the power is turned off;
• A modern control system can control and manage the operation of not only the boiler itself, but also the underfloor heating, hot water supply, radiators;
• A reliable fuel supply system performs its task stably and silently;

In one of our previous reviews, we considered an automatic hot water boiler at the Prometheus coal. However, the Polish "Defro" is a more advanced system with a wide range of options and adjustments.

We talked about the design, capabilities and advantages of Defro long-burning boilers. Now let's find out what the owners think about them, who have already managed to evaluate the capabilities of these devices in real conditions:

When planning a heating system for my country cottage, I considered several models of automatic heating boilers and eventually settled on Defro AKM DUO. At the moment I use crushed fine-grained coal in it, the burner burns it normally, there are no cakes. The only point is that the coal needs to be dry. If used wet, the heat transfer is significantly reduced. I tried to burn firewood in manual mode: a full firebox of birch firewood burns out in 3 hours, although there is a high inertia.

Ivan Sergeevich, Omsk
Photo 4: Small, low-capacity coal-fired boiler with Defro AKM Mini bunker

I bought Defro AKM for my private house quite recently, so far I just installed it and tied it up, started small fires. As for the boiler, I want to say the following, it is made very high quality, it looks attractive. A lot of settings and modes, it’s hard to figure it out right away. As a fuel, I use grade D coal with fractions of 0-30 mm. According to the first impressions, it burns very well, the burning interval between servings picked up the optimal equal to 3 minutes, set the blowing to 40%. The temperature in the heating system rises quickly. The main feature of the Defro burner is that it does not sinter cakes - the output is just ash.

Oleg Viktorovich, St. Petersburg
Photo 5: Installation and connection of the automatic boiler "Defro" in the boiler room

For a long time choosing between coal and pellets, I came across a boiler with a Defro AKM Uni universal burner. I tried to heat with coal, but having stopped the floor of the bunker, I did not find the optimal settings so that there were no cakes. I tried to mix coal with pellets 50 to 50, there are no cakes - normal ash. In short, I will understand, adjust. Easy to clean, everything is available. It is better to do this with a special vacuum cleaner, the procedure is much faster.

Valery Pavlovich, Moscow

For more information about Defro brand boilers, see the following video:

Defro boilers with automatic coal supply are a new generation of solid fuel heating devices. In our country, they are not yet very popular, mainly because of their high cost. Prices for some models exceed half a million rubles. Agree, not everyone can buy such a device. And in most cases, for many country country houses, so common in our country, a simple and inexpensive model is suitable, such as a steel heating boiler with a Siberia Hephaestus hob.

Coal boiler for heating a private house: traditional, long burning, pyrolysis

A coal boiler for heating a private house is a great alternative to gas boilers. It is often installed in regions where there is no gas main. Coal is a common and therefore affordable fuel. It is easy to buy, and the price will not be very high. Modern coal-fired stoves and boilers feature several important technical innovations to improve their efficiency and economy.

Pyrolysis type coal boilers

Types by combustion method

A coal-fired boiler can be classified in different ways, depending on the method of burning fuel, they distinguish:

• traditional units (combustion occurs from the bottom up);
• long-burning boilers on coal;
• pyrolysis.

In addition, automatic and semi-automatic coal-fired boilers are popular, they will also be discussed below. Consider each type of equipment separately.

Direct combustion - bottom-up

The principle of ignition here is this: fuel is poured into the combustion chamber. The air required for combustion enters through the grate from below, and combustion occurs from the bottom of the fuel heap, spreading upwards. These are classic boilers, known to everyone for a long time.

Currently, they are characterized by a long fuel filling interval due to the creation of specially designed combustion chambers, water jackets, air supply channels to the furnace, as well as many innovations and functions. At the same time, this type of boiler equipment still remains the cheapest due to its simple design and, often, due to the impossibility of automatic control.

Long burning coal boiler

Here, the combustion of fuel occurs in reverse: from top to bottom. The order of ignition of the unit has also been changed: first, coal is poured, and then it is burned in the upper layer of the pile. Then, for the purpose of the oxidation process, through a special air supply system, it is supplied not from below, but from above, directly into the combustion zone. In the case of such combustion, fuel loading is needed much less frequently.

Long burning coal boiler Unilux

The only thing that needs to be taken into account is the finicky of solid fuel boilers for long-term burning on coal to the quality and moisture content of the fuel. If coal is low in calories, then, no matter how much you want, you will not be able to squeeze out much heat. When using wet fuel, the boiler will go into smoldering mode for a very long time, and will practically not give off heat, since all the energy will be spent on evaporating water. At this time, a lot of soot is formed, the level of heat output decreases, the boiler and smoke outlets become clogged.

The situation is aggravated by the accumulation of condensate. Due to the fact that the heating unit does not warm up, the moisture evaporates and turns into condensate, mixes with soot, flows back into the combustion chamber and chimney, often flowing out of the boiler and forming a puddle. With everything, you can feel an unpleasant smell. Therefore, if you use wet coal, be aware that the chances of achieving high-quality heating are reduced to zero, and you risk simply damaging the structure.

Long-burning coal boilers for private houses are very demanding on fuel, the fuel humidity should not exceed 15%!

There are rules for sintering - only weakly sintering grades should be used, however, the instructions for all devices contain quality recommendations that should be taken into account. Another difference between a coal-fired boiler is that it cannot be “refilled”. Only after burning one portion, you can lay another portion so as not to disrupt the whole process. Therefore, these are units with a cyclic principle of operation.

Although such boilers are rather capricious, they can be an excellent solution because of their energy independence, efficiency with fuel quality, reliability and undemanding maintenance.

Pyrolysis is an efficient way to burn fuel

A coal pyrolysis boiler requires laying fuel only once every 20-30 hours, certain models generally heat up to 4-6 days. However, the process of burning here is much more complicated.

All devices are controlled automatically, require forced air supply to the afterburner. This means that the functioning of the system depends on the mains.

The difference between the pyrolysis unit and the design: there are two combustion chambers.

Fuel is put into the first furnace, coal is decomposed into coke and gases. The second contains hot gases, afterburning takes place here.

The principle of operation of such devices is as follows: after the coal is ignited, the automation reduces the air supply, while the fuel does not burn, but smolders. In this mode, a large amount of gases are released, which are also amenable to combustion. They circulate to another chamber, where they are also mixed with air and burned. As a result, the fuel is processed almost completely. This can explain the long burning and economical effect (in order to obtain the same amount of heat energy, less coal fuel is required).

It is possible to single out the disadvantage of a pyrolysis automatic coal boiler - a high price. But it is worth saying that the cost pays off quite quickly due to economical fuel consumption. The requirements for coal and firewood in these units are the same as for devices with an upper combustion principle.

Boiler with automatic coal supply

The automatic boiler on coal differs from the traditional one in that it contains additional devices. Automatic devices do not require the constant presence of the owner nearby, increase system performance and minimize fuel consumption and the amount of ash remaining.

Automation functions:

1. It controls the coal supply to the combustion chamber. The design implies a filling hopper with an auger (or drum) for automatic fuel supply. For all that, the user needs to replenish the fuel supply in the bunker only once every few days (from three to ten).
2. Monitors the air supply to the combustion zone. Optimum supply and initial air heating also contribute to uniform coal combustion and equipment efficiency. The coal-fired boiler with automatic fuel supply has efficiency 90% (this is more compared to other types of structures: a conventional boiler - 70%).
3. Automatically dumps ash with movable grates.

The auto mode of the device is adjusted by the parameters that the owner sets. In accordance with the temperature values ​​​​for heating water and heating indoors, automation activates combustion or maintains a smoldering mode for up to five days. Thanks to continuous combustion, it is powerful to ignite once per heating season.

The principle of automatic fuel supply to a solid fuel boiler

The principle of operation of automation is not complicated. Depending on the degree inside the boiler equipment, liquid capacity, pressure force, commands are sent to the air supply sensor. If the air velocity increases or the supply decreases, combustion increases or decreases accordingly. It also adjusts the water heating temperature inside the heat exchanger.

For the operation of an automatic boiler on coal, electricity is required, therefore such units are classified as volatile. They need the presence of a network (battery, socket).

Coal equipment is 20-40% more expensive than wood-burning units. But built-in automation makes it possible to reduce heating costs. According to user reviews, fuel savings can sometimes reach 50%. Thus, it can be argued that coal heating is one of the most profitable for private residential buildings, workshops, workshops ...

Types by material of manufacture

In addition to different combustion methods, boilers can vary in material, that is, they can be made of cast iron or steel. The two options have their own advantages and disadvantages, which should be considered when choosing the right device. Let's give a brief description:

• steel (a special boiler is taken for manufacturing) burns out faster, is less resistant to corrosive processes, but does not cause problems during repairs;
• cast iron is resistant to corrosion and boasts a long service life. However, it can burst from a temperature difference or impact. Moreover, cracks cannot be welded; a complete replacement of the damaged part will be necessary.

There is one more nuance: for the installation of equipment made of cast iron, you will need a separate foundation (if its weight with the coolant in the circuit, fuel and chimney exceeds 700 kg). Many consider it an excellent option for a device made of these two materials: a cast-iron combustion chamber and a steel body.

What are all types of coal boilers fired with?

Fuel for this type of equipment also has its own differences. Property owners should take care of the selection, delivery and proper storage of the right amount of fuel in advance. Coal fuel today can be purchased from many companies, but not everyone is aware of the difference between one type of coal and another. The market currently offers the following fuel options:

1. Long-flame coal. You can guess that this type of fuel burns very quickly and releases a lot of heat. It is often installed for heating houses outside the city, as well as summer cottages.
2. Gas - this is the name of coal due to the fact that when burned it releases a large amount of gas, which can be burned in pyrolysis devices. This is an excellent option for gas-fired boilers, because when burned, a lot of heat is released.
3. Anthracite is a type of coal with a long burning time. This is an excellent solution for modern boilers, because anthracite emits a lot of heat energy and burns slowly, without emitting pyrolysis gases.

Be sure to take care of the proper storage of coal. It must be protected from rain, and also not stored in conditions of high humidity.

It is advisable to protect the fuel from damp cold wind, it would be nice to find a spacious dry room for storage. This is one of the drawbacks of all solid fuel units: it is necessary to look in advance for where to store coal so that it retains all its useful properties.

Automatic coal boiler is a real alternative to traditional coal, gas and diesel boilers. They are cherished"golden mean » between boiler serviceability and fuel costs.

A significant advantage of automatic coal-fired boilers is that, unlike simple solid fuel boilers, they do not require constant attention and time-consuming maintenance. The cost of heating a private house or facility is significantly reduced. Cost price1 kW heat 50-80 kopecks.

The consumption of coal in automatic boilers is an order of magnitude less than in traditional ones (on average in 1,5-2 times). The efficiency of the automatic solid fuel boiler is another advantage, their real Efficiency 80-90%, in contrast to traditional coal, where the declared by the manufacturer Efficiency 80-84%, but in practice efficiency less than 55-60% .

Automatic long burning coal boilers fractional coal up to 50 mm is used, and when it is burned, the fuel burns more completely, due to which ash is obtained by an order of magnitude less and the need to remove ash occurs every 4-7 days (during fuel loading). It's hard to believe, but it's a fact, not an advertisement. You have seen smoke coming from the chimney in an ordinary coal boiler. And in automatic coal boilers it is invisible, only when ignited.