The latest heating appliances. Classification of heating devices. Heated electric floors
Automation and malfunctions of boilers Bosch Gaz 6000 W
Automatic control for gas boilers Bosch Gaz 6000 W
The control panel of Bosch 6000 W gas convection boilers with the Cotronic 3 data bus allows you to control the heating system depending on room temperature.
Two types of Bosch regulators are recommended for these wall-mounted convection gas boilers.
Programmable room temperature controller OpenThermTM CR12005
Rice. 7. Combination of the programmable room temperature controller OpenThermTM CR12005 with the control panel of the Bosch 6000 gas convection boiler
Purpose and functions:
OpenThermTM programmable thermostat for boiler control with Cotronic 3 data bus.
Communication with the controller via a two-wire bus.
Two-wire bus technology, reverse polarity protection.
Simple intuitive settings for temperature control and cooking control hot water.
Preset weekly programs with six switching points. Possibility to manually change the program for each day of the week.
LCD display with digital and graphic display of work status.
Display of the current heating and DHW temperature, outdoor temperature (only if a temperature sensor is present), indication of the boiler burner operation status and error codes.
Possibility of remote reset of the boiler error.
Using the OpenThermTM protocol.
The air temperature setting range in the control room is 7...39 °С with a setting step of 0.5 °С.
Room temperature controller TRZ 12-2
Fig.8. Combination of room temperature controller TRZ 12-2 (on/off) with control panel for gas convection boiler Bosch Gaz 6000 W
Description and functions of the controller
The TRZ 12-2 room temperature controller is recommended for on-off regulation of the burner flame and control of the circulation pump of gas wall-mounted boilers.
Weekly programming of time intervals.
Three operating modes: "Normal", "Economic", "Automatic".
Holiday function (up to 99 days).
Frost prevention function.
Display of date and current time, automatic change of summer/winter time (synchronization with the system).
Room temperature adjustment range from +5 to +39 °C.
Faults shown on the display of Bosch 6000 boilers
A7 - The hot water temperature sensor is defective.
Check for damage or short circuit in the temperature sensor and its wires, replace if necessary.
Ad - Boiler temperature sensor not recognized.
Check boiler temperature sensor and connecting wire
C1 - Low fan speed.
Check mains voltage.
C4 - The differential pressure switch does not open when the fan is off.
Check differential pressure switch.
C6 - Differential pressure switch does not close.
Check differential pressure switch and outlet pipes flue gases.
C7 - The fan does not work.
Check the fan and its cable with plug, replace if necessary.
CE - Insufficient filling pressure heating system.
Add water.
d7 - The gas fittings of the Bosch Gaz 6000 W wall-mounted boiler are faulty.
Check connecting wire.
E2 - Faulty flow temperature sensor (open circuit).
Check for damage or short circuit in the temperature sensor and its wire, replace if necessary.
E9 - The heat exchanger temperature limiter has tripped.
Check for damage to the heat exchanger temperature limiter and its connecting wire, replace if necessary.
Check the operating pressure in the heating system.
Check temperature limiter, replace if necessary.
Check pump start, replace pump if necessary.
Check fuse, replace if necessary.
Remove air from Bosch 6000 W boiler.
Check the water circuit of the heat exchanger, replace if necessary.
Check the flue gas temperature limiter and its connecting wire for damage, replace if necessary.
EA - No flame detected.
Check the protective conductor connection.
Check if the gas cock is open.
Check gas supply pressure, correct if necessary.
Check the electrical connection.
Check electrodes with wires, replace if necessary.
Check the flue gas system, clean or repair if necessary.
Check gas setting, correct if necessary.
For natural gas: check gas flow switch, replace if necessary.
When working with combustion air intake from a room, check the air supply to the room and the ventilation openings.
Clean the heat exchanger.
Check gas fittings, replace if necessary.
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OPERATION AND REPAIR OF BOILERSProterm Panthera Proterm Skat Proterm Bear Proterm Cheetah Evan
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Right choice, competent design and quality installation heating systems are a guarantee of warmth and comfort in the house during the entire heating season. Heating must be of high quality, reliable, safe, economical. To choose the right heating system, you need to familiarize yourself with their types, features of installation and operation of heating devices. It is also important to consider the availability and cost of fuel.
Types of modern heating systems
A heating system is a complex of elements used to heat a room: a heat source, pipelines, heating devices. Heat is transferred with the help of a coolant - a liquid or gaseous medium: water, air, steam, fuel combustion products, antifreeze.
Heating systems of buildings must be selected in such a way as to achieve the highest quality heating while maintaining comfortable air humidity for a person. Depending on the type of coolant, the following systems are distinguished:
- air;
- water;
- steam;
- electrical;
- combined (mixed).
Heating devices of the heating system are:
- convective;
- radiant;
- combined (convective-radiant).
Scheme of a two-pipe heating system with forced circulation
As a heat source can be used:
- coal;
- firewood;
- electricity;
- briquettes - peat or wood;
- energy from the sun or other alternative sources.
The air is heated directly from the heat source without the use of an intermediate liquid or gaseous heat carrier. The systems are used to heat private houses of a small area (up to 100 sq.m.). Installation of heating of this type is possible both during the construction of a building and during the reconstruction of an existing one. A boiler, heating element or heating element serves as a heat source. gas-burner. The peculiarity of the system lies in the fact that it is not only heating, but also ventilation, since the internal air in the room is heated and the fresh air coming from outside. Air streams enter through a special intake grille, are filtered, heated in a heat exchanger, after which they pass through the air ducts and are distributed in the room.
Adjustment of temperature and degree of ventilation is carried out by means of thermostats. Modern thermostats allow you to pre-set a program of temperature changes depending on the time of day. The systems also operate in air conditioning mode. In this case, the air flows are directed through the coolers. If there is no need for space heating or cooling, the system works as a ventilation system.
Diagram of an air heating device in a private house
Installation of air heating is relatively expensive, but its advantage is that there is no need to warm up the intermediate coolant and radiators, due to which fuel savings are at least 15%.
The system does not freeze, responds quickly to changes temperature regime and warms up the room. Thanks to filters, the air enters the premises already purified, which reduces the number of pathogenic bacteria and contributes to the creation of optimal conditions to maintain the health of people living in the house.
The lack of air heating is overdrying of the air, burning out oxygen. The problem is easily solved by installing a special humidifier. The system can be upgraded to save money and create a more comfortable microclimate. So, the recuperator heats the incoming air, due to the output to the outside. This reduces the energy consumption for its heating.
Additional purification and disinfection of air is possible. To do this, in addition to the mechanical filter included in the package, electrostatic fine filters and ultraviolet lamps are installed.
air heating with additional devices
Water heating
This is a closed heating system, it uses water or antifreeze as a coolant. Water is supplied through pipes from the heat source to the heating radiators. AT centralized systems the temperature is regulated at the heating point, and in individual - automatically (using thermostats) or manually (tap).
Types of water systems
Depending on the type of connection of heating devices, the systems are divided into:
- single-pipe,
- two-pipe,
- bifilar (two-furnace).
According to the method of wiring, they distinguish:
- top;
- bottom;
- vertical;
- horizontal heating system.
In single-pipe systems, the connection of heating devices is in series. To compensate for the loss of heat that occurs during the successive passage of water from one radiator to another, heaters with different heat transfer surfaces are used. For example, cast iron batteries with a large number of sections can be used. In two-pipe, a parallel connection scheme is used, which allows you to install the same radiators.
The hydraulic mode can be constant and variable. In bifilar systems, heating devices are connected in series, as in single-pipe systems, but the heat transfer conditions for radiators are the same as in two-pipe ones. Convectors, steel or cast iron radiators are used as heating devices.
Scheme of two-pipe water heating country house
Advantages and disadvantages
Water heating is widespread due to the availability of the coolant. Another advantage is the ability to equip the heating system with your own hands, which is important for our compatriots who are accustomed to relying only on their own strength. However, if the budget allows not to save, it is better to entrust the design and installation of heating to specialists.
This will save you from many problems in the future - leaks, breakthroughs, etc. Disadvantages - freezing of the system when turned off, a long time for warming up the premises. Special requirements apply to the coolant. Water in the systems must be free of impurities, with a minimum salt content.
To heat the coolant, a boiler of any type can be used: on solid, liquid fuel, gas or electricity. Most often used gas boilers, which involves connecting to the highway. If this is not possible, then usually set solid fuel boilers. They are more economical than electric or liquid fuel designs.
Note! Experts recommend choosing a boiler based on a power of 1 kW per 10 sq.m. These figures are indicative. If the ceiling height is more than 3 m, the house has large windows, there are additional consumers, or the premises are not well insulated, all these nuances must be taken into account in the calculations.
closed system home heating
In accordance with SNiP 2.04.05-91 "Heating, ventilation and air conditioning", the use of steam systems is prohibited in residential and public buildings. The reason is the insecurity of this type of space heating. Heaters heat up to almost 100°C, which can cause burns.
Installation is complex, requires skills and special knowledge, during operation there are difficulties with the regulation of heat transfer, noise is possible when the system is filled with steam. Today, steam heating is used to a limited extent: in industrial and non-residential premises, in pedestrian crossings, and heating points. Its advantages are relative cheapness, low inertia, compactness of heating elements, high heat transfer, no heat loss. All this led to the popularity of steam heating until the middle of the twentieth century, later it was replaced by water heating. However, in enterprises where steam is used for industrial needs, it is still widely used for space heating.
Boiler for steam heating
Electric heating
This is the most reliable and easiest type of heating in operation. If the area of the house is not more than 100 m, electricity is a good option, but heating a larger area is not economically viable.
Electric heating can be used as an additional in case of a shutdown or repair of the main system. It is also a good solution for country houses in which the owners live only occasionally. Electric fan heaters, infrared and oil heaters are used as additional heat sources.
Convectors, electric fireplaces, electric boilers, floor heating power cables are used as heating devices. Each type has its own limitations. So, convectors heat the rooms unevenly. Electric fireplaces are more suitable as decorative element, and the operation of electric boilers requires significant energy costs. The underfloor heating is mounted with advance consideration of the furniture arrangement plan, because when it is moved, the power cable may be damaged.
Scheme of traditional and electric heating of buildings
Innovative heating systems
Separately, mention should be made of innovative heating systems, which are becoming increasingly popular. The most common:
- infrared floors;
- heat pumps;
- solar collectors.
infrared floors
These heating systems have only recently appeared on the market, but have already become quite popular due to their efficiency and greater economy than the usual electric heating. Warm floors are powered by the mains, they are installed in a screed or tile adhesive. Heating elements (carbon, graphite) emit infrared waves that pass through flooring, heat up the bodies of people and objects, from which, in turn, the air heats up.
Self-adjusting carbon mats and foils can be mounted under furniture legs without fear of damage. "Smart" floors regulate the temperature due to the special property of the heating elements: when overheated, the distance between the particles increases, the resistance increases - and the temperature decreases. Energy costs are relatively low. When the infrared floors are turned on, the power consumption is about 116 watts per linear meter, after warming up it decreases to 87 watts. Temperature control is provided by thermostats, which reduces energy costs by 15-30%.
Infrared carbon mats are convenient, reliable, economical, easy to install
Heat pumps
These are devices for transferring thermal energy from a source to a coolant. In itself, the idea of a heat pump system is not new; it was proposed by Lord Kelvin back in 1852.
How it works: A geothermal heat pump draws heat from environment and transfers it to the heating system. The systems can also work to cool buildings.
How a heat pump works
There are pumps with open and closed cycle. In the first case, the installations take water from the underground stream, transfer it to the heating system, take thermal energy and return to the place of the fence. In the second - by special pipes a coolant is pumped in the reservoir, which transfers / takes heat from the water. The pump can use the thermal energy of water, earth, air.
The advantage of the systems is that they can be installed in houses that are not connected to the gas supply. Heat pumps are complex and expensive to install, but they save on energy costs during operation.
The heat pump is designed to use the heat of the environment in heating systems
Solar collectors
Solar installations are systems for collecting solar thermal energy and transferring it to a coolant
Water, oil or antifreeze can be used as a heat carrier. The design provides for additional electric heaters that turn on if the efficiency of the solar installation decreases. There are two main types of collectors - flat and vacuum. An absorber with a transparent coating and thermal insulation is installed in the flat ones. In vacuum, this coating is multilayer, in hermetically sealed collectors a vacuum is created. This allows you to heat the coolant up to 250-300 degrees, while flat installations can only heat it up to 200 degrees. The advantages of the installations include ease of installation, low weight, and potentially high efficiency.
However, there is one “but”: the efficiency of the solar collector depends too much on the temperature difference.
Solar collector in the domestic hot water and heating system Comparison of heating systems shows that there is no ideal heating method
Our compatriots still most often prefer water heating. Usually, doubts arise only about which specific heat source to choose, how best to connect the boiler to the heating system, etc. And yet there are no ready-made recipes suitable for absolutely everyone. It is necessary to carefully weigh the pros and cons, take into account the features of the building for which the system is selected. If in doubt, a specialist should be consulted.
Video: types of heating systems
In order for the long-awaited warmth to come into the home, it is not enough just to burn the fuel in the furnace and load the coolant with the calories received. It is necessary to transfer the precious cargo to the premises that need it without unjustified losses. This is exactly what heaters do.
The most important place among them is water heating devices. Water as a heat carrier has many advantages: it has high fluidity, it is ecologically impeccable, it is affordable.
Heating appliances hydraulic heating systems are radiators, convectors and water (not to be confused with electric!) Underfloor heating. There are also smooth and cast-iron finned tubes, but they are mainly used for heating industrial buildings.
Radiator translated from Latin - "radiant", up to 30% of the heat flux it gives off in the form of radiation, the rest - in the form of convection. In a convector, the convection phenomenon that gave it its name (from the Latin convectio - bringing, delivery) accounts for over 90% of the heat flow. In city apartments and modern suburban housing, heating devices are the main "acting heroes" of heating systems. In city apartments and modern suburban housing, heating devices are the main elements of heating systems. Heating appliances, with rare exceptions, are always in sight, and design is important for them. According to marketers, he is given priority by up to 50% of buyers. However, beauty that is difficult to ration is an important, but not the only characteristic that the buyer pays attention to.
The choice of heating equipment
First of all, the buyer pays attention to the thermal power of the device. . has improved markedly in recent years thermal insulation of premises. The result is that much less thermal energy is spent on heating them than a decade ago. But during the same time, the number of household appliances (computers, microwaves, audio systems, etc.), whose total effect on the room temperature cannot be ignored.
nota bene SINGLE AND TWO PIPE SYSTEMS
In a single-pipe system, heaters are connected in series. As a result, each subsequent coolant comes colder than the previous one. That is, the temperature depends on the distance of the radiator from the heat source. Such a system is difficult to regulate, and the heating devices used in it must have low hydraulic resistance. With a two-pipe heating system, the coolant is supplied through one pipe and discharged through the other, which allows parallel, independent connection of heating devices. Another advantage of the "two-tube" is that it allows you to maintain low operating pressures in the system, thereby increasing the service life of communications and making it possible to use cheaper thin-walled radiators. Such schemes are most common in Western Europe. In Russia, however, especially in houses built in the 1950s–80s, single-pipe systems predominate.
Therefore, even today the problem of maintaining the optimum temperature, the possibility of its correction is relevant. The consumer needs regulated heat. Heat that can lead to a reasonable compromise between two opposing desires - not to feel discomfort and pay less for thermal energy, which rises in price every year. Such heat is brought into the house by easily controlled heaters that adequately respond to changes in air temperature (it’s very good if they work in automatic mode).
It is also an axiom that the consumer should receive absolutely safe heat. That is, completely excluding even the minimal possibility of mechanical and thermal injuries. A modern heater should be pleasant not only externally, but also to the touch. Although the temperature of the water circulating in it may approach 90-95 °C, the temperature of the enclosure should not exceed the absolutely safe 40-45 °C. This is important both for furniture and for electrical appliances that are undesirable to be placed next to heating ones. Modern radiators and convectors have reduced the previously quite extensive "exclusion zone" to zero. And now, in the immediate vicinity of them, you can without any fear place TVs, refrigerators and even expensive leather furniture.
For a modern city dweller, who spends almost twenty-four hours a day within four walls, it is very important that he is also warmed by healthy warmth. Lower than the old conventional batteries, the temperature of the outer surface and an increase in the proportion of convection - these are the two main factors that ensure a more even distribution of air temperature in the room, eliminate the causes of drafts, and also contribute to the natural normalization of humidity, preventing the formation of mold and fungi in the room and, as a result, improve the well-being of the people who live in these premises.
Hot water heating systems tend to shrink in size, which in principle does not affect the heat supply.
The design of heating devices is not only expressive forms or eye-catching coloring, but also small sizes. The evolution of heating devices along the path of reducing their mass and volume does not come from aesthetic considerations alone. The small size is also economical. The heater is smaller (that is, its own mass and the amount of coolant contained in it at a time), which means that its thermal inertia is smaller, it responds faster to temperature changes, changing to the desired mode. For example, a heating system with JAGA copper-aluminum radiators reaches its full capacity in just 10 minutes.
The desire to minimize the volume occupied by the heating device, brought to an absolute, is expressed in the production of the mini series, presented in the assortment of many manufacturers. These devices are so small (their height is only 8–10 cm) that they can simply be hidden under the floor, which, however, is not at all necessary - a radiator or convector can serve as an interior decoration no less than a stylish interior door, original lamp or a panel on the wall. But to hide communications (valves and piping) under the casing is quite reasonable for any size.
What are they made from?
Radiators and convectors are made from various materials– steel, cast iron, aluminium, combinations of several metals (bimetal radiators).
When choosing a radiator for your home, you need to pay attention to the following characteristics:
- working and test (or pressure testing) pressure; usually their ratio is in the range of 1.3–1.5;
- nominal heat flow (flow determined under normalized conditions: temperature difference - 70 ° C, coolant flow rate - 0.1 kg / s when it moves in the device according to the "top-down" scheme, Atmosphere pressure– 1013.3 GPa);
- dimensions (length, height, depth, center-to-center distance);
- mass and a value derived from it - specific material consumption (measured in kg / kW);
- price.
Radiators
Cast iron radiators. Cast iron has a high thermal conductivity. For these reasons, heaters made from it can be used in systems with large pressure drops and poor water treatment (increased aggressiveness, contamination, scale pieces). Just all these qualities are possessed by single-pipe systems prevailing in multi-storey construction.
Cast iron radiators have been produced for over 100 years. This is a kind of classic, on which more than one generation of our fellow citizens was “brought up”, usually calling this heater a battery. Until the 1960s, almost the entire range of heating appliances in our country was formed from batteries. And today, this heater, prematurely written off by many, still holds up to 70% of the Russian market.
Modern heating radiators have a good design and high heat dissipation.
In our country, cast-iron radiators are most often used, consisting of two-channel sections connected to each other. The number of sections is determined by the calculated heating surface. Single-channel, and abroad multi-channel (up to 9 channels in one section) cast-iron radiators are also used.
Their disadvantages include high weight, a significant percentage of factory defects - cracks and cavities resulting from poor-quality casting and reducing a potentially very long service life. According to the regulations, the warranty period for radiators is 2.5 years from the date of commissioning or sale within the warranty period of storage, and manufacturers and sellers promise at least several decades of flawless service for these devices. Sometimes cast-iron radiators are reproached for the lack of an attractive appearance (remember: "accordion battery"). However, the use modern design and powder paints can give charm to these veterans.
Systems in which cast-iron radiators are involved, due to the large thermal inertia, are not easy to regulate. Although there is a way out of this situation, and in some models, by reducing the capacity of the sections, it is possible to effectively use thermostatic elements (such, for example, RTD-G, RTD-N thermostats from Danfoss).
Domestic products prevail in this class of heating devices. Among the foreign one can distinguish cast iron sectional radiators firms Roca(Spain), Viadrus(Czech Republic), Biasi(Italy), "Santechlit"(Belarus), Turkish radiators Ridem.
Steel panel radiators formed from two stamped sheets. In our country, their production began in the 1960s. They are distinguished from sectional cast iron ones by their lower weight (specific gravity per 1 kW is approximately three times lower) and thermal inertia. They are considered "sissies" because they are more sensitive to hydraulic shocks that occur when the system is stopped or started and are afraid of corrosion provoked by frequent drains or high oxygen content in the coolant. In systems where there are multiple “higher than normal” pressure surges, it is not necessary to count on the long service life of steel panel radiators. Typically, the operating pressure of devices of this type does not exceed 9 atm.
expert opinion V.V. Kotkov
Commercial Director of HitLine Group of Companies
It can be argued that the proportion of progressive (in relation to the classic cast-iron ones that still prevail) designs of radiators is increasing. Today, up to 5 million sections are produced annually in Europe aluminum radiators. To a large extent, the development of this production is stimulated by the Russian market, where the demand for them annually increases by 5-10%. Therefore, leading Western companies are trying to adapt their products to Russian conditions as much as possible (the problems with water treatment that exist in our country, high unstable pressure in systems central heating etc.). Although, by tradition, many Russian construction companies give priority to cast-iron radiators, the number of firms working with aluminum is steadily increasing. After all, an aluminum radiator is not just a private technical solution, but a solution to a whole range of problems related to efficiency, safety and design. He is able to fit into modern interior, it does not need to be masked, spending a lot of money on it.
Steel panel radiators are widely used in low-rise construction. They are especially appropriate for a two-pipe heating system, which is preferred in cottage construction. In multi-storey buildings, it is reasonable to install them if there is an individual heating point, i.e., a boiler room. Three-quarters of steel panel radiator sales are from the private developer, high-end residential and civil buildings. The most famous models of firms in our country are: VSZ(Slovakia), Dia Norm, Preussag, Kermi(Germany), Korado(Czech Republic), DeLonghi(Italy), Stelrad(Holland), Purmo(Poland), Roca(Spain), DemirDokum(Turkey), Impulse West(England, but assembly in Italy), Dunaferr(Hungary).
Tubular and sectional the radiators are outwardly similar, although they are structurally different - there are no tubular sections as such, and the tubes are connected by two monolithic collectors. Both have an attractive appearance and organically fit into almost any interior. The streamlined shape of the radiator eliminates the possibility of injury to a person. The small capacity of the sections contributes to effective thermoregulation. And if some of its elements are made of a finned tube, then it is possible, without changing the linear dimensions, to significantly increase the power of the radiator.
The working pressure of tubular steel radiators is higher than that of panel radiators - 10 or more atm.
In our market, this type of radiators is represented mainly by German brands Bemm, Arbonia, Kermi.
Aluminum called radiators made of an alloy of aluminum with silicon (the content of aluminum itself is from 80 to 98%). Aluminum is a material with high thermal conductivity, but with high requirements for chemical composition coolant. The disadvantage of radiators made of aluminum-silicon alloy with a high content of silicon is the generation of hydrogen upon contact with water. The excellent design of most radiators somewhat spoils the automatic air release valve installed on each device, since active hydrogen evolution occurs during operation.
A significant part Russian market aluminum radiators are occupied by products of Italian companies: Rovall, Industrie Pasotti, Global, Alugas, Aural, Fondital, Giacomini, Nova Florida. There are also Spanish radiators Roca, Czech Radus, English Wester, etc.
Bimetal radiators. They look like aluminum. Sections consist of two thin-walled steel pipes(channels for the passage of the coolant), pressed under pressure with high-quality aluminum alloy. The logic of this symbiosis is based on the fact that aluminum has a high thermal conductivity, and steel has strength, which guarantees the operation of the device at excess pressure. Italian firms are the actual monopolists in the production of bimetallic radiators. The most famous trademark- Sira.
Bimetal radiators are both durable and efficient.
Convectors. The basis of the convector design is a heating element enclosed in a casing. Leaking to it from below, the cooled room air heats up and rises up. Due to this, more than 90% of the heat is transferred by convection.
Most widespread convectors received in autonomous systems. They are especially effective at low coolant temperatures. So, they are able to warm up the room at a water temperature of only 40 ° C. For the convenience of the user, the convector is equipped with an air valve and a drain tube. The built-in thermostat and the regulator of a pressure of water do its operation economic.
The convector fits especially harmoniously into the modern architectural environment, which actively uses large windows, bay windows, winter gardens etc.
Structurally, it can have four solutions. Radiator convectors are a combination of two devices, reflected in the name itself. They are installed near windows, on the floor or on small stands. Skirting convectors are located in the floor under big windows. The low height (90–100 mm) does not require niches, and a weak convective flow can be increased by a slowly rotating fan. Convectors recessed into the floor - best option for living quarters on the first floors. The device is placed in a kind of shaft, passing along the window cold air freely enters the convector, and the flow warm air provides natural circulation in the room. And finally, convectors covered with a decorative screen. Unlike radiators, a closed convector does not lose heat transfer at all, on the contrary, the screen helps to increase traction.
Pipes for water heating
The functioning of heating devices of hydraulic systems is impossible without pipes. The first polymer (polyvinyl chloride) pipes were made in 1936 in Germany. The first pipeline of them was built in the same place in 1939. But the active introduction of polymer pipes in water supply and heating systems began in the mid-1950s, and in our country since the early 1970s.
Both for systems using classic radiators and for underfloor heating, pipes made of cross-linked polyethylene are best suited. They are not afraid of short-term temperature rise up to +110 °C ( normal temperature their operation is usually +95 °C). With all the advantages, they have one minus - a high price.
Used in heating systems propylene pipes. But at the same time, the high coefficient of thermal expansion of the material should be taken into account. The service life of polymer pipes can reach 30 years or more. The gasket must be hidden: they are hidden in skirting boards, shafts, channels or floor structures. If heating systems use polymer pipes, then in order to protect them from exceeding the parameters of the coolant, it is necessary to provide for the installation of automatic control devices.
The advantages of plastic and metal combine metal-plastic pipes. They are combined with other materials, do not allow oxygen to pass through, and due to the smooth inner surface, they have less resistance to leakage than steel, which, in conditions of mass use, saves a lot of energy. Guarantee period service - at least 20 years, but, as a rule, in reality it reaches 30-50 years. For comparison, according to the State Construction Committee of the Russian Federation, galvanized steel pipes in internal systems serve an average of 12-16 years, and the "black" - half as much.
Competing devices for hot water heating systems
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Warm floors
It is logical to make a smooth transition from pipes to water heated floors. This heating system has many advantages. Firstly, low (40–55 °C) coolant temperature contributes to energy savings. Secondly, due to the participation in the heat emission of the entire floor surface, an almost ideal horizontal and close to ideal vertical temperature distribution is ensured. So, if the floor surface temperature is 22-25 ° C, then the air temperature at head level is 19-22 ° C. People, according to research by hygienists, feel most comfortable if their head is a little colder than their feet. In the hot season, running water with a temperature of 10–12 ° C through pipelines can effectively cool the room. Thirdly, water warm floor make it possible to rationally use the living space.
In new buildings with bulk concrete floors system floor heating consists of several layers: concrete slab, hydro, sound and heat insulation, film, pipes, concrete screed(the most common concrete grade not lower than M-300 is used), a cement layer for leveling the floor and coating. In old buildings, the dry laying method is used, when the heating pipes are installed in the insulation of the carrier layer in special metal plates that ensure uniform heat distribution.
A water heated floor can also be installed under a wooden floor mounted on beams. To do this, from the board, chipboard, moisture resistant plywood or DSP (cement-bonded particle board with a thickness of at least 20 mm) a subfloor is made.
Fastening pipes in circuits is carried out using reinforcing mesh and wire, fastening tape and mounting brackets.
In accordance with Russian regulations, the average temperature of the heated floor should not exceed 26 °C. Therefore, before instructing the water warm floor the role of the main heating system, it is necessary to carefully calculate whether the heat "removed" from it is enough for the room or whether a backup system is still needed.
One of the main elements of water heating systems - a heater - is designed to transfer heat from heat carriers to a heated room.
To maintain the required room temperature, it is required that at each moment of time the heat loss of the room Qp be covered by the heat transfer of the heater Qpp and pipes Qtp.
The scheme of heat transfer of the heater Qpr and pipes to compensate for the heat loss of the room Qp and Qdop during heat transfer Qt from the side of the water coolant is shown in fig. 24.
Rice. 24. Scheme of heat transfer of a heater located at the outer fence of the building
The heat Qt supplied by the coolant for heating this room should be greater than the heat loss Qp by the amount of additional heat loss Qadd caused by increased heating building structures building.
Qt \u003d Qp + Qadd
The heating device is characterized by the area of the heating surface Fpr, m2, calculated to ensure the required heat transfer of the device.
According to the predominant method of heat transfer, heating devices are divided into radiation (ceiling radiators), convective-radiation (devices with a smooth outer surface) and convective (convectors with a ribbed surface).
When heating rooms with ceiling radiators (Fig. 25), heating is carried out mainly due to radiant heat exchange between heating radiators (heating panels) and the surface of the building structures of the room.
Rice. 25. Suspended metal heating panel: a - with a flat screen; b - with a wave-shaped screen; 1 - heating pipes; 2 - visor; 3 - flat screen; 4 - thermal insulation; 5 - wavy screen
The radiation from the heated panel, falling on the surface of fences and objects, is partially absorbed, partially reflected. In this case, the so-called secondary radiation arises, which is also eventually absorbed by the objects and enclosures of the room.
Due to radiant heat exchange, the temperature of the inner surface of the fences increases compared to the temperature during convective heating, and the surface temperature of the inner fences in most cases exceeds the temperature of the air in the room.
With panel radiant heating, due to the increase in the temperature of the surfaces in the room, an environment favorable for humans is created. It is known that a person's well-being improves significantly with an increase in the proportion of convective heat transfer in the total heat transfer of his body and a decrease in radiation to cold surfaces (radiative cooling). This is exactly what is provided with radiant heating, when the heat transfer of a person by radiation decreases due to an increase in the temperature of the surface of the fences.
With panel radiant heating, it is possible to lower the normal (normative for convective heating) air temperature in the room (on average by 1-3 ° C), and therefore the convective heat transfer of a person increases even more. It also improves a person's well-being. It has been established that under normal conditions, people's well-being is ensured at an indoor air temperature of 17.4 ° C with wall heating panels and at 19.3 ° C with convective heating. Hence, it is possible to reduce the consumption of thermal energy for space heating.
Among the disadvantages of the panel-radiant heating system, it should be noted:
Some additional increase in heat loss through external fences in those places where heating elements are embedded in them; -
The need for special fittings for individual control of heat transfer of concrete panels;
Significant thermal inertia of these panels.
Devices with a smooth outer surface are sectional radiators, panel radiators, smooth-tube devices.
Devices with a ribbed heating surface - convectors, ribbed tubes (Fig. 26).
Rice. 26. Schemes of heating devices various kinds(cross section): a - sectional radiator; b - steel panel radiator; c - smooth-tube device of three pipes; g - convector with a casing; D - a device of two finned tubes: 1 - channel for the coolant; 2 - plate; 3 - rib
According to the material from which heating devices are made, metal, combined and non-metallic devices are distinguished. Metal appliances are mainly made of gray cast iron and steel (sheet steel and steel pipes). Copper pipes, sheet and cast aluminum and other metals are also used.
In combined appliances, a heat-conducting material (concrete, ceramics, etc.) is used, into which steel or cast-iron heating elements (panel radiators) or finned metal pipes are embedded, and a non-metallic (for example, asbestos-comeptpy) casing (convectors).
Non-metallic appliances include concrete panel radiators with embedded plastic or glass pipes or with voids, as well as ceramic, plastic and other radiators.
By height, all heaters are divided into high (more than 650 mm high), medium (more than 400 to 650 mm), low (more than 200 to 400 mm) and plinth (up to 200 mm).
According to the magnitude of thermal inertia, devices of small and large inertia can be distinguished. Fast-response devices have a small mass and can accommodate a small amount of water. Such devices based on metal pipes small sections (for example, convectors) quickly change heat transfer to the room when adjusting the amount of coolant admitted into the device. Devices with large thermal inertia - massive, containing a significant amount of water (for example, concrete or sectional radiators), heat transfer is changed slowly.
For heating appliances, in addition to economic, architectural and construction, sanitary and hygienic and production and installation requirements, thermal engineering requirements are also added. The device is required to transfer from the coolant through a unit area to the room the greatest heat flux. To fulfill this requirement, the device must have an increased value of the heat transfer coefficient Kpr, in comparison with the value of one of the types of sectional radiators, which is taken as a standard (cast iron radiator type H-136).
In table. 20 shows thermal performance and conventional signs mark other indicators of devices. The plus sign indicates positive indicators of the devices, the minus sign - negative ones. Two pluses indicate indicators that determine the main advantage of any type of device.
Table 20
Design of heating devices
A sectional radiator is a device of a convective-radiation type, consisting of separate columnar elements - sections with round or elliptical channels. Such a radiator emits about 25% of the total heat flux transmitted from the coolant into the room with radiation (the remaining 75% - by convection) and is called a "radiator" only by tradition.Radiator sections are cast from gray cast iron, they can be combined into devices of various sizes. Sections are connected on nipples with gaskets made of cardboard, rubber or paronite.
Various designs of one-, two-, and multi-column sections of various heights are known, but the most common are two-column sections (Fig. 27) of medium (installation height hm = 500 mm) radiators.
Rice. 27. Two-column radiator section: hp - full height; hm - mounting height (construction); b - building depth
The production of cast-iron radiators is laborious, installation is difficult due to the bulkiness and significant mass of the assembled devices. Radiators cannot be considered to meet sanitary and hygienic requirements, since cleaning the intersection space from dust is difficult. These devices have significant thermal inertia. Finally, it should be noted that their appearance does not correspond to the interior of the premises in buildings of modern architecture. These disadvantages of radiators make it necessary to replace them with lighter and less metal-intensive devices. Despite this, cast-iron radiators are the most common heating device at present.
At present, the industry produces cast-iron sectional radiators with a construction depth of 90 mm and 140 mm (type "Moscow" - abbreviated as M, type I Standard - MS and others). On fig. 28 shows the designs of manufactured cast-iron radiators.
Rice. 28. Cast iron radiators: a - M-140-AO (M-140-AO-300); b - M-140; c - RD-90
All cast iron radiators are designed for operating pressure up to 6 kgf/cm2. The heating surface meters of heating devices are a physical indicator - a square meter of the heating surface and a thermotechnical indicator - an equivalent square meter (ekm2). equivalent square meter called the area of the heating device, giving off 435 kcal of heat in 1 hour with a difference in the average temperature of the coolant and air of 64.5 ° C and a water flow rate in this device of 17.4 kg / h according to the flow pattern of the coolant from top to bottom.
Technical characteristics of radiators are given in table. 21.
Heating surface of cast iron radiators and finned tubes
Table 21
Continuation of the table. 21
Steel panel radiators consist of two stamped sheets forming horizontal manifolds connected by vertical columns (column form) or horizontal channels connected in parallel and in series (serpentine form). The coil can be made from a steel pipe and welded to a single profiled steel sheet; such a device is called sheet-tube.
Rice. 29. Cast iron radiators
Rice. 30. Cast iron radiators
Rice. 31. Cast iron radiators
Rice. 32. Cast iron radiators
Rice. 33. Cast iron radiators
Rice. 34. Schemes of channels for the coolant in panel radiators: a - columnar; b - two-way coil, c - four-way coil
Steel panel radiators differ from cast iron ones in their lower mass and thermal inertia. With a decrease in weight by about 2.5 times, the heat transfer rate is no worse than that of cast-iron radiators. Them appearance meets architectural and construction requirements, steel panels are easy to clean from dust.
Steel panel radiators have a relatively small heating surface area, which is why sometimes it is necessary to install panel radiators in pairs (in two rows at a distance of 40 mm).
In table. 22 shows the characteristics of manufactured steel stamped radiator panels.
Table 22
Continuation of the table. 22
Continuation of the table. 22
Concrete panel radiators (heating panels) (Fig. 35) can have concrete heating elements of a serpentine or register shape made of steel pipes with a diameter of 15-20 mm, as well as concrete, glass or plastic channels of various configurations.
Rice. 35. Concrete heating panel
Concrete panels have a heat transfer coefficient close to those of other devices with a smooth surface, as well as a high thermal stress of the metal. Devices, especially combined type, meet strict sanitary-hygienic, architectural and construction and other requirements. The disadvantages of combined concrete panels include the difficulty of repair, large thermal inertia, which complicates the regulation of heat supply to the premises. The disadvantages of attachment-type devices are the increased costs of manual labor in their manufacture and installation, and the reduction in the usable floor area of the room. Heat losses through additionally heated external fences of buildings also increase.
A smooth-tube device is called a device made of several steel pipes connected together, forming channels for a coil or register-shaped coolant (Fig. 36).
Rice. 36. Forms of connecting steel pipes to smooth-tube heaters: a - serpentine form; b - register form: 1 - thread; 2 - column
In the coil, the pipes are connected in series in the direction of movement of the coolant, which increases the speed of its movement and the hydraulic resistance of the device. When the pipes are connected in parallel in the register, the coolant flow is divided, the speed of its movement and the hydraulic resistance of the device decreases.
The devices are welded from pipes DN = 32-100 mm, located from each other at a distance of 50 mm greater than their diameter, which reduces mutual exposure and, accordingly, increases heat transfer to the room. Smooth-tube appliances have the highest heat transfer coefficient, their dust-collecting surface is small and they are easy to clean.
At the same time, smooth-tube devices are heavy and bulky, take up a lot of space, increase the consumption of steel in heating systems, and have an unattractive appearance. They are used in rare cases when other types of devices cannot be used (for example, for heating greenhouses).
Characteristics of smooth-tube registers are given in table. 23.
Table 23
The convector is a convective type device, consisting of two elements - a finned heater and a casing (Fig. 37).
Rice. 37. Schemes of convectors: a - with a casing; b - without casing: 1 - heating element; 2 - casing; 3- air valve; 4 - pipe fins
The casing decorates the heater and increases heat transfer due to the increase in air mobility at the surface of the heater. A convector with a casing transfers up to 90-95% of the total heat flux into the room by convection (Table 24).
Table 24
A device in which the functions of the casing are performed by the fins of the heater is called a convector without a casing. The heater is made of steel, cast iron, aluminum and other metals, the casing is made of sheet materials (steel, asbestos cement, etc.)
Convectors have a relatively low heat transfer coefficient. However, they find wide application. This is due to the ease of manufacture, installation and operation, as well as low metal consumption.
The main technical characteristics of convectors are given in Table. 25.
Table 25
Continuation of the table. 25
Continuation of the table. 25
Note: 1. When installing KP skirting convectors in multiple rows, a correction for the heating surface is introduced depending on the number of rows vertically and horizontally: with a two-row vertical installation 0.97, a three-row installation - 0.94, a four-row installation - 0.91; for two rows horizontally, the correction is 0.97. 2. The indicators of the end and passage models of convectors are the same. Passage convectors have an index A (for example, Hn-5A, H-7A).
A finned tube is a convective-type device, which is a flanged cast-iron pipe, the outer surface of which is covered with jointly cast thin ribs (Fig. 33).
The outer surface area of a finned tube is many times greater than the surface area smooth pipe the same diameter and length. This gives the heater a particularly compact design. In addition, the reduced surface temperature of the fins when using a high-temperature coolant, the relative ease of manufacture and low cost determine the use of this thermally inefficient, heavy device. The disadvantages of finned tubes also include an outdated appearance, low mechanical strength of the ribs and the difficulty of cleaning from dust. Ribbed tubes are usually used in auxiliary premises (boiler rooms, warehouses, garages, etc.). The industry produces round ribbed cast-iron pipes 1-2m long. They are installed horizontally in several tiers and connected according to the serpentine scheme with bolts using "kalachi" - flanged cast-iron double taps and counterflanges.
For a comparative thermal performance of the main heating devices in table. 25 shows the relative heat transfer of devices 1.0 m long under equal thermal and hydraulic conditions when using water as a heat carrier (heat transfer of a cast-iron sectional radiator 140 mm deep is taken as 100%).
As you can see, sectional radiators and convectors with a casing are distinguished by high heat transfer per 1.0 m of length; convectors without a casing and especially single smooth pipes have the lowest heat transfer.
Relative heat output of heaters with a length of 1.0 m Table 26
Selection and placement of heating devices
When choosing the type and type of heating device, the purpose, architectural layout and features of the thermal regime of the room, the place and duration of stay of people, the type of heating system, the technical, economic and sanitary and hygienic indicators of the device are taken into account.
Rice. 38. Cast iron ribbed tube with round ribs: 1 - channel for the coolant; 2 - ribs; 3 - flange
To create a favorable thermal regime, devices are chosen that provide uniform heating of the premises.
Metal heaters are installed mainly under the light openings, and under the windows the length of the device is desirable not less than 50-75% of the length of the opening, under the shop windows and stained-glass windows the devices are placed along their entire length. When placing devices under windows (Fig. 39a), the vertical axes of the device and the window opening must match (a deviation of not more than 50 mm is allowed).
Devices located at the outer fences contribute to an increase in the temperature of the inner surface in the lower part of the outer wall and window, which reduces the radiation cooling of people. The ascending currents of warm air created by the devices prevent (if there are no window sills blocking the devices) the ingress of cooled air into the working area (Fig. 40a). In southern regions with a short warm winter, as well as during a short stay of people, heating devices can be installed near the inner walls of the premises (Fig. 39b). This reduces the number of risers and the length of heat pipelines and increases the heat transfer of devices (by about 7-9%), but there is an unfavorable movement of air with a low temperature near the floor of the room (Fig. 40c).
Rice. 39. Placement of heating devices in rooms (plans): a - under the windows; b - at the inner walls; p - heater
Rice. 40. Schemes of air circulation in rooms (sections) at different locations of heating devices: a - under windows without a window sill; b - under windows with a window sill c - at the inner wall; p - heater
Rice. 41. Location under the window of the heater room: a - long and low (preferably); b - high and short (undesirable)
Vertical heating devices are installed as close as possible to the floor of the premises. With a significant rise of the device above the floor level, the air near the floor surface may be supercooled, since the circulation flows of heated air, closing at the level of the device, do not capture and do not warm up the lower part of the room in this case.
The lower and longer the heater (Fig. 41a), the more even the temperature of the room and the better the entire volume of air warms up. A tall and short device (Fig. 41b) causes an active rise of a jet of warm air, which leads to overheating of the upper zone of the room and the lowering of cooled air on both sides of such a device into the working area.
The ability of a tall heater to cause an active upward flow of warm air can be used to heat rooms of increased height.
Vertical metal appliances, as a rule, are placed openly against the wall. However, it is possible to install them under window sills, in wall niches, with special fencing and decoration. On fig. 42 shows several methods for installing heaters in rooms.
Rice. 42. Accommodation heating appliances- in a decorative cabinet; b - in a deep niche; c - in a special shelter; g - behind the shield; d - in two tiers
Sheltering the device with a decorative cabinet having two slots up to 100 mm high (Fig. 42a) reduces the heat transfer of the device by 12% compared to its open installation against a blank wall. To transfer a given heat flux to the room, the area of the heating surface of such a device must be increased by 12%. Placing the device in a deep open niche (Fig. 42b) or one above the other in two tiers (Fig. 42e) reduces heat transfer by 5%. However, hidden installation of devices is possible, in which the heat transfer does not change (Fig. 42c) or even increases by 10% (Fig. 42d). In these cases, it is not required to increase the area of the heating surface of the device or even reduce it.
Calculation of the area, size and number of heating devices
The area of the heat-releasing surface of the heating device is determined depending on the type of device adopted, its location in the room and the connection scheme to the pipes. In residential premises, the number of appliances, and therefore the required heat transfer of each appliance, is usually determined by the number of window openings. AT corner rooms add another device placed in a blank end wall.The task of the calculation is, first of all, to determine the area of the external heating surface of the device, which, under the calculated conditions, provides the necessary heat flow from the coolant to the room. Then, according to the catalog of devices, based on the estimated area, the nearest trade size of the device is selected (the number of sections or the brand of the radiator (the length of the convector or finned tube). The number of sections of cast-iron radiators is determined by the formula: N=Fpb4/f1b3;
where f1 is the area of one section, m2; type of radiator accepted for indoor installation; b4 - correction factor, taking into account the way the radiator is installed in the room; b3 is a correction factor that takes into account the number of sections in one radiator and is calculated by the formula: b3=0.97+0.06/Fp;
where Fp is the calculated area of the heater, m2.