Solid fuel boilers are varied in design. The more complex they are, the more expensive the device is, as well as its installation and maintenance. Simpler models are not always convenient, but understandable and easy to use. This type of equipment includes a classic cast iron boiler. Not all parts of such a unit are made of cast iron; some of the elements of the device are made of ordinary steel with increased heat resistance.
Features of the devices
The main feature of the device under consideration is its heat exchanger. It has a characteristic sectional structure, assembled on special squeegees (nipples) without the use of a weld. The power of the boiler depends on the number of such heating units - the more there are, the stronger its heat transfer. Building on individual elements makes it easier to solve problems with breakdowns and replacement with new failed parts.
Most often, due to the impressive weight, a solid fuel cast iron boiler is made in a floor version. A solid concrete base is required for such a structure.
Positive and negative sides
If we take a cast iron and steel unit for comparison, the following can be noted:
- Cast iron is more durable and can regularly serve a quarter of a century, while steel structures are rarely nursed for more than 12 years.
- The material is resistant to corrosion of both electrochemical and chemical nature.
- The heat exchanger does not need to be cleaned as often as steel, because there is practically no rust formation inside.
- Prefabricated sections can be easily untwisted and replaced with a new one, or simply reduce the size of the radiator.
The negative side of cast iron and all products made from this material is the risk of thermal shock. If cold water gets inside the hot metal, it is more likely to burst, which never happens with ordinary steel. Also, during transportation, it is necessary to protect the product from mechanical stress. As a result of the fall, part of the heat exchanger may break off.
If you strictly adhere to the operating conditions, a cast-iron or steel boiler in most cases nurses its life.
Varieties of ovens
There are different modifications of heat generators. By the type of solid fuel used, there are:
- Coal combustion units. They are distinguished by the increased strength of the walls of the combustion chamber.
- Pellet solid fuel heat generators. They work on wood and agricultural pellets.
- Long burning devices. They can be designed only for wood material or universal on any solid fuel.
- Heat generators of pyrolysis action with a cast iron heat exchanger.
In addition to the type of fuel, boiler equipment may differ in power and design of the furnace.
You should not experiment and use fuel that is not provided for in the passport data for the device, such actions will obviously lead to a malfunction of the hardware or the entire system as a whole.
Classic type devices
Devices of the design under consideration are non-volatile and require an electrical connection.The first view is shaped like a vertically standing rectangle made of metal with two doors on the facade. There is a classic firebox and an ash collection compartment with a blower. Such a solid fuel boiler with a cast iron heat exchanger is atmospheric without forced blowing.
Volatile models are no different in design from the one described above, but they have a lower door adapted for the installation of a pellet burner with automation. The burner itself is equipped with a fan, electric ignition, cleaning and control system.
Pyrolysis devices
Pyrolysis units with a sectional heat exchanger are intended only for the use of firewood and wood waste. Here, the afterburning method is used, in which the amount of harmful emissions into the atmosphere is reduced. The number of heating sections in such systems determines the capacity of the boiler plant.
Most often, modern pyrolysis tanks are designed to work in a closed coolant circulation system. Therefore, a protective group must be present in the circuit to protect it from overheating.
Design features
The simplest solid-fuel sectional apparatus is assembled from the following units:
- Metal body. This is the outer casing of the product, which at the same time performs a load-bearing function - inside and outside, various components of the unit are attached to it.
- Heat exchanger. It is placed inside the furnace and is a set of cast iron sections connected by threaded hardware with sealed refractory gaskets and equipped with outlets to the water circuit.
- The combustion chamber. It is made of thick-walled steel sheet and has the shape of a vertical rectangle.
- Door for loading firewood or other solid fuels. Located on the front panel at the top. It has a double wall: the inner one is made of heat-resistant thick-walled steel to adjoin the combustion chamber and the outer one is made of thin metal. The door is also equipped with a locking handle.
- Ash pan. Located under the loading chamber, it also has a double design, complete with a handle for closing and an oxygen supply flap from the bottom.
- Smoke exhaust pipe. This element is usually welded to the back or top of the body. Inside there is a chimney damper with a control lever displayed on the front panel.
The supporting part of the furnace is usually made of two channels welded parallel to each other in the same plane.
Before installing the unit in a permanent place, you need to organize a concrete platform for it in the room or check the quality and strength of the existing screed.
How to choose a cast iron boiler
The algorithm for selecting boiler equipment with a cast iron heat exchanger does not differ from the selection of any other boiler. Main criteria:
- Installation power. Traditionally, a kilowatt of thermal energy is enough to heat 10 square meters of a room.
- The number of contours.
- The type of the entire heating system. There is equipment that is designed only for open or closed circuits.
- Overall indicators, if there are restrictions on the size of the furnace.
Often the consumer also focuses on the manufacturer. Therefore, it is better to study information about the most popular and practical units for which you can always find spare parts.
Correctly selected cast-iron boiler equipment will correspond to the declared operating parameters if the wiring of the heating circuit is correctly organized.
Manufacturers of popular models
The Czech manufacturer Protherm produces low-power and high-power solid fuel heat generators. A design feature is the implementation of a heat exchanger combined with a firebox. The devices can operate with gravity and forced circulation of the heat carrier.
The German company Buderus specializes in the production of universal models of boiler equipment for any type of solid fuel. The power regulator in such devices works according to the thermal principle.
