The types of heating devices are determined by their design, which determines the method of heat transfer (convective or radiation heat transfer may predominate) from the external surface of the devices to the room.
There are six main types of heating devices, radiators, panels, convectors, finned tubes, smooth tube devices and air heaters.
By the nature of the outer surface heating devices can be with a smooth (radiators, panels, smooth-tube appliances) and ribbed surface (convectors, finned tubes, air heaters).
Based on the material from which heating appliances are made, a distinction is made between metal, combined and non-metallic appliances.
Heating device diagrams
a - radiator, b - panels, c - convector, e - finned pipe, d - smooth-tube device.
Metal devices are made of cast iron (from gray cast iron) and steel (from sheet steel and steel pipes).
In combined appliances, a concrete or ceramic mass is used, in which steel or cast iron heating elements (heating panels) are embedded, or finned steel pipes placed in a non-metallic (for example, asbestos-cement) casing (convectors).
Non-metallic appliances are concrete panels with embedded glass or plastic pipes or with voids without pipes at all, as well as porcelain and ceramic radiators.
By height, all heating devices can be divided into high (over 600 mm in height), medium (400-600 mm) and low (<400 мм). Низкие приборы высотой менее 200 мм называются плинтусными.
Diagrams of five types of heating devices are shown in the figure. A heater used primarily for heating air in ventilation systems.
A radiator is usually called a convective-radiation type device, consisting of individual columnar elements - sections with round or ellipse-shaped channels. The radiator releases about 25% of the total amount of heat transferred from the coolant into the room by radiation, and is called a radiator only by tradition.
The panel is a convection-radiation type device of relatively shallow depth, without any gaps along the front. The panel transmits a slightly larger portion of radiation than the radiator heat flow, however, only the ceiling panel can be classified as a radiation-type device (emitting more than 50% of the total amount of heat by radiation).
The heating panel may have a smooth, slightly ribbed or wavy surface, columnar or serpentine channels for the coolant.
A convector is a convective type device consisting of two elements - a finned heater and a casing. The convector transfers at least 75% of the total heat into the room by convection. The casing decorates the heater and helps increase the speed of natural air convection near the outer surface of the heater. Convectors also include baseboard heating devices without a casing.
A finned tube is an openly installed convective type heating device, in which the area of the external heat-transmitting surface is at least 9 times greater than the area of the internal heat-receiving surface.
Double column radiator section
hп - total height, hм - installation (construction) height, l - depth; b - width.
A smooth-tube device is called a device consisting of several steel pipes connected together, forming columnar (register) or coil-shaped (coil) channels for the coolant.
Let's consider how the requirements for heating devices are met.
1. Ceramic and porcelain radiators are usually made in the form of blocks, they are distinguished by a pleasant appearance, and have a smooth surface that is easy to clean from dust. They have fairly high thermal performance indicators: kp p = 9.5-10.5 W/(m 2 K); f e /f f >1 and lower surface temperature in comparison with metal devices. When using them, metal consumption in the heating system is reduced.
Ceramic and porcelain radiators are not widely used due to insufficient strength, unreliable connections with pipes, difficulties in manufacturing and installation, and the possibility of water vapor penetrating through ceramic walls. They are used in low-rise construction and are used as non-pressure heating devices.
2. Cast iron radiators - widely used heating devices - are cast from gray cast iron in the form of separate sections and can be assembled into devices of various sizes by connecting the sections on nipples with heat-resistant rubber gaskets. Various designs of single-, double- and multi-column radiators of various heights are known, but the most common are double-column medium and low radiators.
Radiators are designed for a maximum operating (the term is usually used) coolant pressure of 0.6 MPa (6 kgf/cm 2) and have relatively high thermal performance indicators: k pr = 9.1-10.6 W/(m 2 K) and f e / f f ≤1.35.
However, the significant metal consumption of radiators [(M=0.29-0.36 W/(kg K) or 0.25-0.31 kcal/(h kg °C)] and other disadvantages cause their replacement with lighter and less metal-intensive devices It should be noted their unattractive appearance when installed openly in modern buildings.In sanitary and hygienic terms, radiators, except for single-column ones, cannot be considered meeting the requirements, since cleaning the intersectional space from dust is quite difficult.
The production of radiators is labor-intensive, installation is difficult due to the bulkiness and significant mass of the assembled devices.
Corrosion resistance, durability, layout advantages with good thermal performance, well-organized production contribute to high level production of radiators in our country. Currently, a two-column cast iron radiator of type M-140-AO with a section depth of 140 mm and intercolumn inclined fins, as well as type S-90 with a section depth of 90 mm are produced.
3. Steel panels differ from cast iron radiators in that they are lighter in weight and cost. Steel panels are designed for operating pressure up to 0.6 MPa (6 kgf/cm2) and have high thermal performance indicators: k pr = 10.5-11.5 W/(m 2 K) and f e /f f ≤1.7.
The panels are made in two designs: with horizontal collectors connected by vertical columns (columnar) and with horizontal channels connected in series (coil-shaped). The coil is sometimes made of steel pipe and welded to the panel; The device in this case is called a sheet-tube device.
The panels satisfy architectural and construction requirements, especially in buildings made of large building elements, are easily cleaned of dust, and allow their production to be mechanized using automation. On the same production areas, it is possible to produce per year instead of 1.5 million m 2 ENP cast iron radiators up to 5 million m 2 ENP steel. Finally, when using steel panels, labor costs during installation are reduced due to a reduction in metal mass to 10 kg/m2 enp. Reducing mass increases the thermal stress of the metal to 0.55-0.8 W/(kg K). The distribution of steel panels is limited by the need to use high-quality cold-rolled sheet steel with a thickness of 1.2-1.5 mm, resistant to corrosion. When manufactured from ordinary sheet steel, the service life of the panels is reduced due to intense internal corrosion. Steel panels, except sheet-tube ones, are used in heating systems with deoxygenated water.
Stamped steel panels and radiators various designs widely used abroad (in Finland, USA, Germany, etc.). In our country, medium and low steel panels with columnar and coil-shaped channels are produced for single and paired (in depth) installation.
4. Concrete heating panels are manufactured:
- with concrete-coated coil or column-shaped heating elements made of steel pipes with a diameter of 15 and 20 mm;
- with concrete, glass or plastic channels of various configurations (metal-free panels).
These devices are placed in the enclosing structures of premises (combined panels) or attached to them (attached panels).
When using steel heating elements concrete heating panels can be used at a coolant operating pressure of up to 1 MPa (10 kgf/cm2).
Concrete panels have thermal performance indicators close to those of other smooth devices: k pr = 7.5-11.5 W/(m 2 K) and f e / f f ≈1, as well as high thermal stress of the metal. The panels, especially combined ones, meet strict architectural, construction, sanitary, hygienic and other requirements.
However, concrete panels, despite their compliance with most of the requirements for heating devices, are not widely used due to operational shortcomings (combined panels) and installation difficulties (attached panels).
5. Convectors have relatively low thermal performance indicators k pr = 4.7-6.5 W/(m 2 K) and f e / f f<1, для отдельных типов конвекторов до 0,6. Тем не менее их производство во многих странах растет (при сокращении производства чугунных отопительных приборов) из-за простоты изготовления, возможности механизации и автоматизации производства, удобства монтажа (масса всего 5-8 кг/м 2 энп). Малая металлоемкость способствует повышению теплового напряжения металла прибора. M=0,8-1,3 Вт/(кг К) . Приборы рассчитаны на рабочее давление теплоносителя до 1 МПа (10 кгс/см 2).
Convectors can have steel or cast iron heating elements. Currently, convectors with steel heaters are produced:
- plinth convectors without casing (type 15 KP and 20 KP);
- low convectors without casing (such as “Progress”, “Accord”);
- low convectors with casing ("Comfort" type).
Plinth convector type 20 KP (15 KP) consists of a steel pipe with a diameter d y = 20 mm (15 mm) and closed fins 90 (80) mm high with a pitch of 20 mm, made of sheet steel 0.5 mm thick, tightly fitted on the pipe . Convectors 20 KP and 15 KP are produced in various lengths (every 0.25 m) and are assembled at the factory into units consisting of several convectors (in length and height), pipes connecting them and control valves.
It should be noted that the advantage of using baseboard convectors is the improvement of the thermal conditions of rooms when they are placed in the lower zone along the length of windows and external walls; in addition, they take up little space in the depth of the premises (building depth is only 70 and 60 mm). Their disadvantages are: the consumption of sheet steel, which is not used effectively for heat transfer, and the difficulty of cleaning the fins from dust. Although their dust-collecting surface is small (less than that of radiators), they are still not recommended for heating rooms with increased sanitary and hygienic requirements (in medical buildings and children's institutions).
The low convector of the “Progress” type is a modification of the 20 KP convector, based on two pipes connected by common fins of the same configuration, but of greater height.
A low convector of the “Accord” type also consists of two parallel steel pipes d y = 20 mm, through which coolant flows sequentially, and vertical fin elements (height 300 mm) made of sheet steel 1 mm thick, mounted on pipes with gaps of 20 mm. The finning elements that form the so-called front surface of the device are U-shaped in plan (rib 60 mm) and open to the wall.
The Accord type convector is manufactured in various lengths and installed in one or two rows in height.
In a convector with a casing, air mobility increases, which increases the heat transfer of the device. The heat transfer of convectors increases depending on the height of the casing.
Convectors with a casing are used mainly for heating public buildings.
A low convector with a “Comfort” type casing consists of a steel heating element, a collapsible casing made of steel panels, an air outlet grille and a valve for air regulation. In the heating element, rectangular fins are mounted on two pipes d y = 15 or 20 mm with a pitch of 5 to 10 mm. The total mass of the heater metal is 5.5-7 kg/m2 enp.
The convector has a depth of 60-160 mm, is installed on the floor or on the wall and can be through the movement of the coolant (for horizontal connection with another convector) and end (with a roller).
The presence of a valve for air regulation allows you to connect convectors in series with coolant without installing fittings to regulate its quantity. Convectors can also be equipped with artificial convection when installed in a fan casing of a special design.
6. Finned pipes are made of gray cast iron and are used at operating pressures up to 0.6 MPa (6 kgf/cm2). The most common are flanged cast iron pipes, on the outer surface of which thin cast-in round ribs are placed.
Due to the high finning ratio, the outer surface of a finned tube is many times larger than the surface of a smooth pipe of the same diameter (inner diameter of the finned tube is 70 mm) and length. The compactness of the device, the reduced surface temperature of the fins when using a high-temperature coolant, the comparative ease of manufacture and low cost determine the use of this thermally ineffective device: k pr = 4.7-5.8 W/(m 2 K); f e /f f =0.55-0.69. Its disadvantages also include unsatisfactory appearance, low mechanical strength of the ribs and difficulty in cleaning from dust. Finned tubes also have a very low thermal stress of the metal: M = 0.25 W/(kg K).
They are used in industrial premises where there is no significant dust emission, and in auxiliary premises with temporary occupancy of people.
Currently, round finned pipes are produced in a limited range of lengths from 0.75 to 2 m for horizontal installation. Steel-iron finned tubes are being developed, which include finned tube type PK with rectangular fins 70 X 130 mm. This pipe is characterized by ease of manufacture and relatively low weight. The base is a steel pipe d y =20 mm, cast into cast iron fins 3-4 mm thick. Two longitudinal plates are cast on top of the ribs to protect the main fins from mechanical damage. The device is designed for operating pressure up to 1 MPa (10 kgf/cm2).
Diagram of a convector with a casing
1 - heating element, 2 - casing, 3 - air valve.
For comparative thermal characteristics of the main heating devices, the table shows the heat transfer of devices 1 m long.
Heat transfer of heating devices 1 m long at Δt av = 64.5° and water flow 300 kg/h.
| Heating devices | Device depth, mm | Heat transfer | |
| W/m | kcal/(h m) | ||
| Radiators: | |||
| - type M-140-AO | 140 | 1942 | 1670 |
| - type S-90 | 90 | 1448 | 1245 |
| Steel panels type MZ-500: | |||
| - single | 18 | 864 | 743 |
| - paired | 78 | 1465 | 1260 |
| Convectors type 20 KP: | |||
| - single-row | 70 | 331 | 285 |
| - three-row | 70 | 900 | 774 |
| Convectors: | |||
| - type “Comfort” N-9 | 123 | 1087 | 935 |
| - type “Comfort-20” | 160 | 1467 | 1262 |
| Finned tube | 175 | 865 | 744 |
As can be seen from the table, deeper heating devices have high heat transfer per 1 m of length; A cast iron radiator has the greatest heat transfer, while a baseboard convector has the least.
7. Smooth-tube devices are made of steel pipes in the form of coils (pipes are connected in series according to the movement of the coolant, which increases its speed and the hydraulic resistance of the device) and columns or registers (parallel connection of pipes with reduced hydraulic resistance of the device).
The devices are welded from pipes d y = 32-100 mm, located at a distance from one another of no less than the selected pipe diameter to reduce mutual radiation and, accordingly, increase heat transfer into the room. Smooth tube devices are used at operating pressures up to 1 MPa (10 kgf/cm2). They have high thermal performance indicators: k pr = 10.5-14 W/(m 2 K) and f e / f f ≤1.8, and the highest values apply to smooth steel pipes diameter 32 mm.
Indicators of heating devices of various types
significant | pressure | Requirements for devices | |||||||||
Technical | architecturally Construction | sanitary hygienic | production Assembly |
||||||||
labor |
|||||||||||
| Radiators: | |||||||||||
Icical and | 2-4 | >1 | - | ++ | + | - | + | ++ | - | - | |
| - cast iron | 6 | Up to 1.35 | - | - | - | + | - | - | - | - | |
| Panels: | |||||||||||
| - steel | 6 | Up to 1.7 | ++ | + | + | - | - | ++ | ++ | + | |
| - concrete | 10 | ~ 1 | + | ++ | + | ± | ++ | + | - | ± | |
| - without casing | |||||||||||
| - with casing | 10 | <1 | ± | + | ± | ± | + | - | ++ | + | |
| 6 | + | - | - | ++ | + | - | - | - | |||
| 10 | Up to 1.8 | - | - | - | - | - | ++ | - | - | ||
| 8 | >1 | - | + | - | ++ | + | - | + | - | ||
Note: The + sign indicates compliance, the sign indicates non-compliance with the requirements for the devices; The ++ sign indicates indicators that determine the main advantage of this type of heating device.
Smooth-tube devices meet sanitary and hygienic requirements - their dust-collecting surface is small and easy to clean.
The disadvantages of smooth-tube devices include their bulkiness due to the limited external surface area, inconvenience of placement under windows, and increased steel consumption in the heating system. Taking into account these disadvantages and unfavorable appearance, these devices are used in production areas where significant dust emission occurs, as well as in cases where other types of devices cannot be used. In industrial premises they are often used to heat skylights.
8. Heaters - compact heating devices of a significant area (from 10 to 70 m2) of the outer surface, formed by several rows of finned pipes; They are used for air heating of premises in local and central systems. Directly in premises, air heaters are used as part of air heating units of various types or for recirculating air heaters. The heaters are designed for a coolant operating pressure of up to 0.8 MPa (8 kgf/cm 2); their heat transfer coefficient depends on the speed of movement of water and air, and therefore can vary widely from 9 to 35 or more W/(m 2 K) [from 8 to 30 or more kcal/(h m 2 ˚C)].
The table shows the indicators of heating devices various types; fulfillment or non-fulfillment of the requirements for devices is conditionally noted.
It doesn’t matter how well the renovation is done in the house and how well the layout of the rooms is planned, because if the heating devices are not working properly in the room, it is unlikely that it will be possible to achieve comfortable living conditions. Therefore, the primary task of owners who are making major renovations to a building or building a new house from scratch is the correct selection and installation of optimal heating devices.
In most families, the leading cost item for utility bills is heating costs. This is also worth considering when choosing heating devices for a heating system in a hardware store, because each device, depending on the design and specification, differs in terms of rated power, heat transfer and efficiency.
In a home heating system, basic heating devices are presented various types radiators and convectors. When choosing a radiator, first of all you should focus on the material from which it is made, since it is this factor that affects the practicality, wear resistance and durability of the devices. When buying a convector, you should take into account its power and the possibility of automatic operation.
Characteristics of devices made of various metals
Today, heating equipment made of such metals as bimetal, steel, cast iron are popular. Let's look at them in more detail.
Bimetal
Innovative bimetallic heating devices are by far the most functional. They ideally complement heating systems of any type and are distinguished by the fact that they combine best sides steel and aluminum batteries. This a light weight, which ensures ease of installation, exceptional heat transfer and an aesthetic appearance that will decorate even a designer-renovated apartment. A radiator reflector installed in accordance with the manufacturer’s recommendations will help improve the efficiency of a bimetallic radiator.
Steel
also have positive heat transfer rates, however, they are less durable due to the fact that the steel is subject to corrosion - therefore, the devices may not be suitable for central heating systems. As for aluminum analogues, they have high efficiency and guarantee effective performance, however, in the heating system they are subject to rapid mechanical wear due to pressure and the action of heavy metal salts present in the coolant. Such radiators often break, so a jumper to the heating battery is needed - it will allow you to replace the device without stopping the functioning of the entire system.
Cast iron
The most primitive option is considered to be cast iron heating devices for water heating systems at home.
Cast iron batteries are durable, wear-resistant and can be used even in systems with poor coolant quality.
However, some owners avoid installing cast iron appliances because of their high weight, which requires the presence of a reliable wall structure for drilling powerful brackets, and their unsightly appearance, which requires the purchase of a box. To install such a device, the owner will need to buy a key for heating radiators and prepare a whole set of auxiliary tools.
Differences in design and operating principles
Commercially available heating devices - convectors, radiators, finned tubes and smooth-tube devices - may differ in design and operating principle. Depending on the design features, heating devices can be placed along the walls or built into specially prepared niches. Moreover, regardless of the type of construction, radiators and pipes operate on the same principle - they use their surface to transfer energy from the heating body - the coolant, through their body into the environment. Oil or water is most often used as a coolant in residential buildings, while in industrial buildings it can be hot steam.
Radiator design
From the design features of radiators, obvious conclusions can be drawn - the larger the surface area of the radiator body in contact with the environment, the more heat it will transfer to the room. To achieve maximum efficiency with small dimensions, manufacturers have proposed compressing the working areas of heating devices and giving them a more compact appearance. Among such developments are panel and, in which the coolant circulates inside special articulated channels.
This solution made it possible to achieve maximum thermal efficiency and effective heat transfer of the radiator while reducing its external dimensions. When such a radiator operates, large volumes of air mass are involved in heat exchange, as a result of which it ensures uniform heating of the room. The thermal efficiency of a radiator depends not only on the volume of air circulating around it, but also on the availability of conditions in the room for natural air convection.
This is worth remembering for owners who use decorative boxes or install furniture in front of the radiator. These objects create barriers to optimal heat distribution, become an obstacle to effective air circulation and reduce the efficiency of the heating device. Therefore, by correctly arranging pieces of furniture in the room, the owner can take the control panel of the heating boiler, select the optimal operating mode and enjoy the comfort in his home.
Convector design
Unlike radiators, a convector works according to a different scheme. The heating controller sends a signal to it and the heating element located under the casing is switched on. Heated air spreads throughout the room by convection and increases temperature regime.
However, if the room uses outdated models of convectors, you will need to install an air humidifier on the heating radiator to maintain optimal level humidity. Old models of convectors dry out the air greatly and contribute to the creation of an uncomfortable microclimate; new models do not have these shortcomings.
Using auxiliary elements to optimize the operation of heating devices
To improve the performance of heating devices connected to the circuit, the owner may need auxiliary equipment. This is a unloading relay for an electric boiler, which allows you to smoothly regulate power and make the operation of heating devices connected to the circuit more efficient, or thermal heads for heating radiators - high-tech devices designed for automatic regulation temperature in the circuit.
It is worth paying attention to GSM heating control - a module that allows you to remotely control the operation of heating devices.
It helps the owner receive reports on the temperature in the room, the health of devices in the circuit, and also allows for remote setting of the operating mode of the heating system. Modern models of remote heating control suggest that the optimal temperature regime can be selected for each room. For this purpose, all heating appliances in the house are equipped with automatic temperature controllers. You can read more about thermostats.
The optimal combination of basic and auxiliary devices in the heating system will allow you to achieve maximum efficient work circuit and will contribute to more economical consumption of energy resources.
One after another, economic crises are hitting the planet, which, coupled with a rapidly decreasing amount of resources, creates a need for the development and use of energy-saving technologies. This trend has not bypassed heating systems, which strive to maintain or even increase their efficiency while consuming significantly less resources. Let's figure out what the new heating technologies for a private house, apartment and industrial premises are by decomposing the heating system into four main components: a heat generator, a heating device, a heating system and a control system.
The boiler heating system is the most productive, although also the most expensive (after electric heaters) of all modern autonomous heating technologies. Although the boiler itself is an invention with ancient history, modern manufacturers managed to modernize it, increasing efficiency and adapting it to different types of fuel. Thus, there are three main (fuel-burning) types of boilers - solid fuel, gas, liquid fuel. Electric boilers that are somewhat out of this classification, as well as combined or multi-fuel boilers, combine the qualities of two or three types at once.
Solid fuel boilers
There is an interesting trend of returning to the traditions of the past and active use solid fuel: from ordinary firewood and coal to special pellets (pellets pressed from wood processing by-products) and peat briquettes.
Solid fuel boilers are divided according to the type of fuel into:
Classic ones “accept” any type of solid fuel without any problems, are extremely reliable and simple (in fact, this is the oldest heat generator in the history of mankind), and are cheap. Disadvantages: “capriciousness” in relation to wet fuel, low efficiency, inability to adjust the temperature of the coolant.
A pellet boiler is a heating device that runs on wood waste compressed into small pellets. They are distinguished by high efficiency, long-term operation on one load, extremely convenient system loading of pellets (filled from a bag or package), the ability to configure the boiler. The only significant drawback is the rather expensive pellets for heating, the price of which ranges from 6900 to 7700 rubles per ton, depending on the ash content and calorific value.
The next type is pyrolysis heating boilers, operating on pyrolysis gas extracted from wood. The fuel in such a boiler slowly smolders rather than burns, due to which it gives off noticeably more heat. Advantages: high efficiency and reliability, adjustable heat transfer, up to half a day of operation without reloading. The only drawback- the need to connect to the electrical network, which is why during power outages the house may be left without heat.
Standard long-burning boilers are loaded with any type of solid fuel, with the exception of wood: coke, brown and hard coal, peat briquettes, pellets. There is another variety, designed specifically for working with wood and slightly different in design. Advantages: work up to five days on oil products and up to two days when loaded with wood. Disadvantages: relatively low efficiency, need for constant cleaning.
Gas boilers
Mains gas is the most economical of all types of fuel, and boilers running on it are considered the most convenient to use and maintain. This is explained by their fully automated operation and absolute safety, for which many sensors and controllers are responsible. They do not have any disadvantages as such, although they do require a gas line or constant delivery of new cylinders.
Liquid fuel boilers
It cannot be said that such heating systems are innovative, but they have been consistently in demand for decades and are therefore worthy of mention. The main types of liquid fuel: diesel fuel and liquefied propane-butane mixture. Advantages over solid fuels: almost complete automation of operation. Disadvantages: extremely high cost of heating, second only to electricity.
Electric heating
It is distinguished by a wide variety of heating systems and individual devices. These are electric convectors (which in turn are in-floor, floor-mounted and wall-mounted), and electric boilers, and fan heaters, and infrared heaters, and oil radiators, and heat guns, and the well-known heated floor. Their common and so far insurmountable drawback is the extremely high cost of heating. The most economical of them are infrared radiators and heated floors.
Heat pumps
These heating systems are modern in the full sense of the word, despite the fact that they appeared back in the 80s. Then they were available only to wealthy people, but now many have gotten used to collecting them by hand, thanks to which they are slowly but surely gaining popularity. A very simplified principle of their operation is to extract heat from the air, water or ground outside the house and transfer it into the house, where the heat is transferred either directly into the air, or first into the coolant - water.
Solar systems
Another rapidly developing technology is solar heating systems, better known as solar panels.
Advantages:
Flaws:
Thermal panels
They are thin rectangular (usually) plates fixed to the wall. The back side of such a plate is covered with a heat-accumulating substance that can heat up to 90 degrees and receives heat from the heating element. Energy consumption is only 50 watts per 1 square meter, unlike older electric fireplaces that require at least 100 watts for the same area. Heating occurs due to the convection effect.
In addition to being economical, thermal panels differ in:
There is only one drawback - thermal panels become unprofitable in the spring and early autumn, when the home only needs a little heating from evening to morning.
Monolithic quartz modules
A unique development by S. Sargsyan - Candidate of Technical Sciences. Externally, the plates are very similar to thermal panels, but the principle of their operation is based on the high heat capacity of quartz sand. The heating element transfers sand thermal energy, after which it continues to heat the home, even when the device is unplugged. The savings, as in the case of thermal panels, are 50% of the costs of standard electric heaters.
PLEN - film radiant electric heaters
This innovative heating system has a device that is as simple as it is ingenious: power cable, heating elements, dielectric film and reflective screen. The heater is fixed to the ceiling, and the infrared radiation it produces heats objects located below. These, in turn, transfer heat to the air.
The main advantages of PLEN:
Thermal hydrodynamic pumps
These devices, also known as cavitation heat generators for heating systems, generate heat by heating the coolant using the principle of cavitation.
The coolant in such a pump rotates in a special activator.
At the sites of rupture of an integral mass of liquid, as a result of an instantaneous decrease in pressure, bubbles-cavities appear, bursting almost instantly. This causes a change in the physicochemical parameters of the coolant and the release of thermal energy.
It is interesting that even with the current level of scientific and technological development, the process of cavitation energy generation is poorly understood. A clear explanation for why the energy gain is greater than its costs has not yet been found.
Air conditioner as a heater
Almost all modern air conditioner models are equipped with a heating function. Oddly enough, the air conditioner has three times the efficiency of standard electric heaters: 3 kW of heat from 1 kW of electricity versus 0.98 kW of heat from 1 kW of electricity.
Thus, an air conditioner for heating in winter can temporarily replace a switched-off heating system or a broken electric fireplace. However, due to the fact that air conditioners do not use heating elements to heat the air, their efficiency drops with every degree of temperature outside the window. In addition, severe frost overloads the device, and operation in this mode can lead to breakdown. The best option would be to use air conditioning in the off-season.
Convectors
Since a convector heating system is an extremely broad concept, and almost every modern heating device uses the convection effect, we will make a reservation in advance that we are talking here only about individual water and electric convectors. They are a finned heater placed in a metal casing.
The air circulating between the ribs of the device heats up and rises, and in its place air masses that have already cooled during this time are drawn in.
This endless circulation is called convection. Based on the heat source, convector heaters are divided into water and electric, and based on location - into in-floor, floor-mounted and wall-mounted. Also, any of them can work on the principle of either natural convection or forced (with a fan).
Although the types of convectors and the features of each of them are a topic for a separate article, we can highlight the general advantages of using these heaters:
So which is more profitable financially?
As a summary of this section, let’s compare the cost of heating using different types of fuel: wood, pellets, coal, diesel fuel, propane-butane mixture, regular main gas and electricity. With average prices for each type of fuel and with average duration heating season in 7 months during this time you will have to spend:
The leader is obvious.
Heating devices
First of all, modern heating radiators are bimetallic and aluminum models. However, there is a stable demand for both steel and cast iron products, which is due to a new approach by manufacturers to the manufacture of seemingly outdated heating devices. Let us briefly describe the advantages and disadvantages of each type.
Aluminum
They are most popular in the post-Soviet space for their price/quality ratio (cheaper than bimetallic, in many ways more reliable than steel and cast iron).
Advantages:
- the best heat transfer among all analogues;
- expensive models can withstand pressure up to 20 bar;
- little weight;
- simplest installation.
Disadvantages: poor corrosion resistance, especially noticeable at the junction of aluminum with other metals;
Bimetallic
Generally recognized as the best type of radiator. They got their name due to the combination of steel (inner layer) and aluminum (casing) in their design.
Advantages:
Disadvantages: high price.
Steel
They are poorly suited for multi-storey buildings and centralized heating systems in general, but show all their best properties in private houses and fit perfectly into heating systems production premises in factories and factories. You can read more about steel heating radiators.
Advantages:
- heat transfer is above average;
- rapid onset of heat transfer;
- low cost;
- aesthetic appearance.
Flaws:
Cast iron
It should be understood that modern cast iron heating radiators are no longer lumpy and heavy relics of the past that “decorated” almost every house during the Soviet era. Modern manufacturers have significantly improved their appearance, making them almost indistinguishable from bimetallic or aluminum models. Moreover, there is a growing fashion for the so-called, the shapes and patterns of which bring the atmosphere of the early 20th century into the house.
Advantages:
Disadvantages: huge weight and the ensuing difficulties with installation (special supports-legs are often required).
Heating system
Most modern country houses use a horizontal heating system, the main difference of which from vertical distributions is the partial (less often - complete) absence of vertical risers.
In Russia, such a type of horizontal system as a single-wire heating system (or single-pipe) is especially popular.
They involve natural movement of water, without a circulation pump. From the heating device, the coolant flows through a riser to the second floor of the building, where it is distributed over radiators and transmission risers.
Water circulation without a pump is made possible by changing the density of hot and cold water.
A single-pipe system has a number of advantages over a two-pipe system:
Control system
Additional benefits can be provided by a heating system controller - a miniature computer device capable of:
How to choose the optimal radiators
Russia is located in a climate zone where heating systems are used for a long time. Sometimes the home is heated even for six months. Therefore, experts recommend a more careful approach to the choice of heating devices.
The modern market offers a huge number of models designed for different operating conditions. Often it is technical features become fundamental criteria to be guided by when purchasing. But there are still a lot of additional nuances, which we will talk about.
Existing requirements
All heating systems have one purpose - they are designed to create comfortable living conditions in winter time of the year. The room temperature should be at least 18–20 degrees, but this is not the only condition that a heating device must meet. Let us outline other criteria and requirements on the basis of which one can judge the effectiveness of a heating device and the degree of its perfection.
Classification of criteria
All criteria are conditionally divided into several groups:
- Sanitary and hygienic. There are standards that limit the maximum surface temperature. Devices should have the smallest horizontal area, which does not allow large amounts of dust to accumulate. The form of the installation should allow for easy cleaning, removing dust and other contaminants, as well as cleaning nearby surfaces.
- Economic. Any installation must guarantee an optimal price-performance ratio, minimizing the costs of manufacturing, metal use and maintenance during operation.
- Architectural and construction. Recently, much attention has been paid to the ergonomics and versatility of devices. They should fit well into existing stylistic concepts and occupy a small amount of space.
- Assembly and production. Any unit must have sufficient strength and reliability. And its installation should not require the involvement of super-professional labor.
- Operational. Modern heating installations must allow heat transfer to be regulated and ensure sufficient heat and water resistance when operating within the maximum permissible technical parameters.
- Thermal engineering. It is important to maximize the heat flow given off by the coolant per unit area of the room.
Finding a heating device that would meet all these requirements is almost impossible, since there are no ideal designs. Therefore, manufacturers are still experimenting in this direction, offering modified installations to potential buyers. This explains the wide range of similar products. Each type meets some of the listed requirements. Therefore, when choosing a unit, it is necessary to focus on priority criteria.
For example, for medical institutions the sanitary and hygienic component is important, for designer interiors- architectural and construction. And in household sphere Most often they pay attention to installation, production and operational requirements, so other indicators may be slightly worse. To understand the priorities in more detail, it is necessary to study the classification of modern heating devices.
Types of Heat Transfer
All heating devices, taking into account the method of transferring heat flow, can be divided into two large groups:
- Convective systems.
- Radiant modes.
Convective devices transfer heat by moving air masses. From school course physicists know that air, when heated, rises, there it cools and falls down. Convective systems consist of installations that heat the air in a room and create natural convection processes in it.
Radiant systems transfer heat using infrared radiation. They act similarly to a natural source of heat - the sun, which heats objects rather than air. Accumulating heat, they then release it to the surrounding space.
Technical features of the convective system
Types of electric convectors
The most striking example of the convective heating method is autonomous and central heating systems. They use various radiators as heating devices.
According to the material of manufacture and the shape of the structure, they are divided:
- For sectional batteries.
- Tubular.
- Panel.
- Plate models.
What are the advantages and disadvantages of each type?
Sectional
Sectional batteries are separate heating units consisting of a different number of sections, which determines the power of the heating device. Sectional radiators can be made from different materials. The most common- these are cast iron models, but analogue products made of steel, aluminum or bimetal have appeared relatively recently. For higher efficiency, they are made in the form of ribs and channels, have different heights and widths of the ribs, as well as manufacturing design.
Almost all of them require a large amount of coolant. Some have significant limitations for use, but they all have one thing in common - the convection mode of operation. To understand where and how a particular device can be used, it is worth paying attention to the technical features of each.
Cast iron sections
Cast iron heating device
Cast iron radiators are the oldest heating device, which today lives a second life. The design familiar from childhood has become outdated, so cast iron radiators began to fit poorly into modern interiors. Manufacturers have not yet been able to find a better alternative, so they have made certain concessions. ABOUT neither changed the shape of the front panel, rounded the corners, reduced the size of the sections, added automation and made a convex volumetric ornament for each section. As a result, the devices were transformed in appearance, so buyers turned their attention to them again.
Cast iron is the only metal that today is ideally suited to the conditions and operating characteristics of a central heating system. It is resistant to corrosion and unpretentious to the quality of the coolant. Cast iron, although it heats up slowly, gives off most of the heat by radiation, heating the room more evenly over its entire height.
Almost all products are designed for an internal system pressure of 9 atmospheres. But they have a large margin of safety, and many years of use of the devices have shown that they are able to function effectively even at an operating pressure of 15 atmospheres. Cast iron has minimal hydraulic resistance, so batteries made from it can be used where natural circulation is provided.
Despite the extensive modernization, manufacturers have not yet been able to eliminate one more drawback. Cast iron products are still heavy, with each section weighing an average of 8kg. Therefore, it is difficult to transport cast iron radiators and install them alone. Cast iron appliances remain difficult to clean, and many people don't like their rough surface.
Aluminum sections
The very first receiver of cast iron products were aluminum sectional radiators. New appliances do not have the disadvantages of cast iron products, but they have completely different disadvantages that are also worth mentioning. But first, the good stuff.
Aluminum radiator
Aluminum installations have improved technical indicators:
- High level of heat transfer and ideal surface plane.
- Improved convection transmission method.
- The light weight of each section is up to one and a half kilograms versus eight.
- Reduced volume of coolant used - 0.25 liters of water are consumed to fill one section.
- Fast heating of the room.
- Possibility of installing automatic units that regulate the operating mode of each section.
- Wide operating pressure range.
Taking into account such technical features, one could call aluminum batteries ideal heating devices, if not for one BUT. The fragile metal is very sensitive to the pH value of the coolant. If it exceeds the permissible standards even a little, aluminum begins to deteriorate from the inside and becomes porous, like a sponge. Therefore, any water hammer will cause a leak.
When using parts made of other metals, electrochemical corrosion occurs, which can also lead to utility accidents. Therefore, it is permissible to use the described products only in autonomous systems, where it is possible to control the quality of the supplied water and use purification filters.
Bimetal sections
Bimetallic heating radiators
An alloy of two metals was supposed to be a compromise between reliability, ease of operation and efficiency. Manufacturers have managed to create a good alternative to cast iron products. Externally bimetallic sections similar to aluminum radiators. They have all their advantages and at the same time are devoid of many disadvantages.
Technologists have figured out how to eliminate contact of the coolant with fragile and capricious aluminum. IN bimetallic radiators water moves through steel pipes that are installed inside an aluminum casing. Steel is a durable material that can withstand operating pressures of up to 30–45 atmospheres. At the same time, the entire product does not weigh much more than aluminum models.
There are no restrictions on the use of bimetallic products today. The inside of steel parts is coated with special polymer compounds, which prevent the development of corrosive phenomena. The only drawback of such radiators is their high price compared to other products. And it is precisely this circumstance that is currently hindering the growth of the popularity of bimetal.
Tubular devices
Radiators in the interior
Tubular batteries are different from sectional design. They are made in the form of vertical curved tubes connected to each other at the bottom and top using manifolds. The efficiency of heat transfer is influenced by various factors - the size of the model, its height, width and diameter of the tubes.
Three types of tubular batteries can be found on sale:
- Steel products.
- Tubular convectors.
- Heated towel rails.
They all differ from each other in a host of design features that are also worth highlighting.
Steel tubular radiators
The technical features of tubular steel instruments are well known. The height of the products can be 0.3 or 3 meters. The thickness of the pipe walls also varies. For example, for Russian manufacturers it is 2mm. The device is designed for a pressure of 10–12 atmospheres, but domestic producers They produce models that can withstand operating pressures of 15–22 atmospheres. The method of heat transfer is dominated by the radiation rather than the converter mechanism.
The smoothness of the bends and the absence of corners makes it easy to wash the device, so the tubular steel radiator- the most hygienic model of all existing ones. It has one drawback - low corrosion resistance. The fact is that steel is susceptible to oxygen oxidation, so the radiator needs to be filled with water all the time. Provide this condition where it operates central system heating is extremely difficult. After all, during the summer, utilities drain water from the common system. Therefore, use tubular models in apartment buildings it is forbidden.
Note! There are no tubular steel batteries that are absolutely resistant to corrosion. But Russian products are manufactured taking into account domestic operating conditions, and European models do not have large pipe wall thickness. Also, European manufacturers do not treat the internal parts of the parts with anything, while Russian tubular devices are coated on the inside with special polymer compounds that increase their service life.
Tubular convectors
Steel tubular convectors
Convector radiators are a new generation of heating devices. In cross section, the tubes of such models are similar to a donut. The pipe has double walls, between which the coolant flows. This design made it possible to double the heat transfer of the devices. At the same time, the efficiency of the process increases due to heat transfer from the walls of the device, as well as through the creation of a converter flow, which is formed between the inner walls of the pipes.
Ease of maintenance, beautiful appearance, completely new design - these are the main advantages of the described device.
Heated towel rails
It is worth mentioning separately another type of tubular heaters - heated towel rails. They perform two functions at once - they heat the bathroom and dry the towels.
Heated towel rails can be connected to central heating, installing them in the heating cycle. In our country, this element is connected to the hot water system, so the device often fails. And all because the steel from which these devices are made is afraid of oxidation processes. When connected to the hot water supply, water enriched with calcium, iron and other impurities enters the radiator, which gradually leads to “overgrowing” of the pipes. As a result, heated towel rails quickly become unusable.
Note! This does not happen when connected to a heating cycle. Therefore, when choosing a model, you should pay attention to the features of its connection. There are models on sale made from different materials. The most common heated towel rails are made of black or of stainless steel, shallow, aluminum or brass. Experts recommend purchasing stainless steel models.
Often non-ferrous metals require compatibility with the materials from which other elements of the system are made. For example, in order for copper heated towel rails to function well and for a long time, it is necessary to connect them copper pipes and fittings, and this is a very expensive pleasure. If this rule is not followed, abrasive wear will not be prevented.
If the model is connected to a domestic hot water system, you should choose dual-circuit products. They have a longer service life. Hot water flows through one circuit and heats the other. In this case, the dryer tubes do not come into contact with the aggressive coolant environment, do not overheat and do not experience system pressure.
Panel batteries
The name itself speaks about the design of such devices. The rectangular shape acts as a heating source. In this case, coolant circulation occurs between steel sheets having vertical channels, which increases usable area installations.
In its finished form, such a unit may contain several panels welded together. They are placed parallel to each other and covered with special powder enamel, and the top and side parts are closed with decorative inserts.
The technical features of this model are:
- The installation is light in weight.
- Products for sale include: different sizes and differing from each other in width and height.
- The device has slight inertia.
- 75% of the heat is transferred using the converter method.
- The operating pressure for each model is different, so it is necessary to select a device taking into account this value.
All of the above indicators can be considered positive. But such a choice also has disadvantages. The first is a little water pressure. The maximum value is 10 atmospheres, so panel radiators are very sensitive to water hammer. But this is not the main thing.
The inner surface of the panels is not protected by anything, so when exposed to oxygen, the steel quickly becomes rusty and “loses weight.” This means that panel devices can only be used for heating in autonomous systems that are constantly filled with water.
Plate batteries
Steel radiator
Plate radiators are convectors in their purest form, the main advantage of which is reliability. The design is always closed on top with an aluminum casing, so you cannot get burned on such batteries. Their heat transfer is 95%. Thermal inertia is negligible.
But the plate device has more disadvantages than advantages. This includes an unpresentable appearance, low heat transfer, and the need to maintain a high coolant temperature. In addition, due to the low intensity of thermal convection, the room is heated ineffectively.
But modern manufacturers are trying to improve such models, combating their negative points. The specialists managed to achieve good luck in this direction. Firstly, copper tubes are now used to make the base, onto which copper and aluminum plates are mounted. Secondly, modern models have original design, which fits perfectly into popular stylistic concepts. And this circumstance is very popular with those who dream of exclusive interiors.
Such a disadvantage as uneven heating of the room can easily turn into an advantage where the ceiling height exceeds standard sizes. Large front halls, lobbies, exhibition stained glass windows, indoor swimming pools, loggias and winter gardens are used here today wall models, linear varieties, as well as devices built into the floor.
The working pressure in plate batteries is 16 atmospheres. There are exclusive specimens in which the operating pressure reaches 37 atmospheres.
So far, manufacturers have not been able to eliminate another drawback of the described option - poor compatibility with current system, as well as difficulties in caring for the device.
Technical features of the radiant system
Heat movement in a radiant system
The radiative system differs radically from the convective system. There is no point in describing the technical features, since studying them is the domain of specialists. But let's take a closer look at the advantages of this heating method and outline the main types of devices.
Positive points
- Radiant heating devices have an efficiency of 95%, which is explained by the direct conversion of electricity into heat. For comparison, for converter systems this figure is 50%. One cannot believe manufacturers’ claims that they were able to achieve 100% of the indicators in this regard. This is contrary to the laws of physics. The efficiency of any device mounted on the wall will drop by 30%. In addition, it “eats” useful space and warms up the air that is under the ceiling. And the person “uses” the already cooled air, which tends to the battery.
- A radiant device warms up a room much faster. Even when it is turned off, the room takes a long time to cool down. And all this happens due to the fact that it is not the air that is heated, but objects that then give off heat themselves.
- The absence of convection eliminates the movement of air masses, as well as temperature differences. As a result, no
- Heating modes in radiant heating devices can be controlled, adjusting the temperature and creating more comfortable conditions.
- The described installations always operate silently. In addition, any unit is easy to install, move to a convenient place, and also dismantle.
- Modern models consume 30% less electricity.
Types of devices
There are two types of radiant devices:
- Long wave models.
- Infrared heaters.
They differ from each other in the different intensity of heating of the heating element. U infrared heaters heating element heats up to 800 degrees, while long-wave heaters only heat up to 250 degrees. But the second type is fireproof, does not burn oxygen, heats the room evenly and creates a very soft, comfortable heat.
Other varieties
Which heated floor is better
There are several other types of heating devices that cannot be classified as either converter models or radiant devices. This is a “warm floor” system and radiant films.
Warm floor
In terms of efficiency, heated floors occupy an intermediate level between convectors and radiant systems. This is currently the most expensive heating option, and also complex and time-consuming. To install heated floors, it is necessary to open the floor, make a screed, lay electric heating mats or a pipeline for hot water.
Therefore, in addition to the cost of the elements themselves, the final price will have to include complex and time-consuming Finishing work. Moreover, the described system is not mobile; dismantling and moving the main elements is impossible without further major repairs.
Emissive films
Emissive films are the latest know-how that is just beginning to appear in Russia. They can become a worthy alternative to heated floors, but so far the capacity of the products is extremely limited.
In addition, the efficiency of the devices is significantly lower than that of long-wave heaters. Therefore, emissive films are not very popular yet. But they are the future, and experts are sure of this.
Generalization on the topic
We have provided a detailed classification of existing heating devices, outlined their technical advantages, as well as the operating features of each. From this information it is clear that there are no perfect designs that could be called universal and effective.
But modern production is capable of providing consumers with a huge range of products, giving them the opportunity to choose an installation taking into account individual requirements. Until recently, it was difficult to find a couple of alternative options. And today is just a transfer existing models can demonstrate the enormous capabilities of modern heating systems.
The right choice, competent design and high-quality installation of a heating system is the key to warmth and comfort in the house throughout the heating season. Heating must be of high quality, reliable, safe, and economical. To choose the right heating system, you need to familiarize yourself with their types, installation features 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 using a coolant - a liquid or gaseous medium: water, air, steam, fuel combustion products, antifreeze.
Heating systems for buildings must be selected in such a way as to achieve the highest quality heating while maintaining air humidity that is comfortable for humans. Depending on the type of coolant, the following systems are distinguished:
- air;
- water;
- steam;
- electrical;
- combined (mixed).
Heating devices for heating systems are:
- convective;
- radiant;
- combined (convective-radiant).
Scheme of a two-pipe heating system with forced circulation
The following can be used as a heat source:
- 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 coolant. The systems are used for heating small private houses (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. The heat source is a boiler, heating element or gas-burner. The peculiarity of the system is that it is not only heating, but also ventilation, since the internal air in the room and fresh air coming from outside are heated. Air flows enter through a special intake grille, are filtered, heated in a heat exchanger, after which they pass through air ducts and are distributed in the room.
Temperature and ventilation levels are controlled using 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, air flows are directed through coolers. If there is no need to heat or cool the room, the system operates as a ventilation system.
Diagram of air heating device in a private house
Installing air heating is relatively expensive, but its advantage is that there is no need to warm up the intermediate coolant and radiators, resulting in fuel savings of at least 15%.
The system does not freeze, quickly responds to changes in temperature and warms up the room. Thanks to filters, air enters the premises already purified, which reduces the number of pathogenic bacteria and contributes to the creation optimal conditions to maintain the health of people living in the house.
The disadvantage of air heating is drying out the air and burning out oxygen. The problem can be easily solved by installing a special humidifier. The system can be improved to save money and create a more comfortable microclimate. Thus, the recuperator heats the incoming air at the expense of the air exhausted outside. This allows you to reduce energy costs for heating it.
Additional air cleaning and disinfection 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. IN centralized systems the temperature is regulated at the heating point, and in individual ones - automatically (using thermostats) or manually (with taps).
Types of water systems
Depending on the type of connection of heating devices, systems are divided into:
- single-pipe,
- two-pipe,
- bifilar (two-furnace).
According to the wiring method, they are distinguished:
- top;
- lower;
- vertical;
- horizontal system heating.
In single-pipe systems, the heating devices are connected in series. To compensate for the heat loss that occurs when water sequentially passes from one radiator to another, heating devices with different heat transfer surfaces are used. For example, cast iron batteries with a large number of sections can be used. In two-pipe systems, a parallel connection scheme is used, which allows the installation of identical radiators.
The hydraulic mode can be constant or variable. In bifilar systems, heating devices are connected in series, as in single-pipe ones, but the conditions for heat transfer of 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 of a country house
Advantages and disadvantages
Water heating is widespread due to the availability of coolant. Another advantage is the ability to install a 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 does not allow saving, 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 switched off, long time to warm up the premises. Special requirements presented to the coolant. The water in the systems must be free of foreign impurities, with a minimum content of salts.
To heat the coolant, any type of boiler can be used: solid, liquid fuel, gas or electricity. Most often used gas boilers, which involves connecting to the main line. If this is not possible, then solid fuel boilers are usually installed. They are more economical than designs that run on electricity or liquid fuel.
Note! Experts recommend selecting a boiler based on a power of 1 kW per 10 square meters. These figures are indicative. If the ceiling height is more than 3 m, the house big 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 unsafety of this type of space heating. Heating appliances reach temperatures of almost 100°C, which can cause burns.
Installation is complex, requires skills and special knowledge; during operation, difficulties arise with regulating heat transfer; when filling the system with steam, noise is possible. 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 heating elements, high heat transfer, no heat loss. All this led to the popularity of steam heating until the mid-twentieth century; later it was replaced by water heating. However, in enterprises where steam is used for production needs, it is still widely used for heating premises.
Steam heating boiler
Electric heating
This is the most reliable and easiest-to-use type of heating. If the house area is no more than 100 m2, electricity is a good option, but heating a larger area is not economically viable.
Electric heating can be used as additional heating in case of shutdown or repair of the main system. Also this good decision for country houses in which the owners live only periodically. How additional sources For heat, electric fan heaters, infrared and oil heaters are used.
Convectors, electric fireplaces, electric boilers, and heated floor power cables are used as heating devices. Each type has its own limitations. Thus, convectors heat rooms unevenly. Electric fireplaces are more suitable as a decorative element, and the operation of electric boilers requires significant energy consumption. Warm floors are installed taking into account the furniture arrangement plan in advance, because moving it may damage the power cable.
Scheme of traditional and electric heating of buildings
Innovative heating systems
Separate 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 cost-effectiveness than conventional electric heating. Heated floors are powered by electricity and are installed in screed or tile adhesive. Heating elements (carbon, graphite) emit infrared waves that pass through flooring, heat up people’s bodies and objects, which in turn heats up the air.
Self-regulating carbon mats and film can be installed under furniture legs without fear of damage. “Smart” floors regulate temperature thanks to a special property of the heating elements: when overheated, the distance between particles increases, resistance increases, and the temperature decreases. Energy consumption is 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 ensured by thermostats, which reduces energy costs by 15-30%.
Infrared carbon mats are convenient, reliable, economical, and easy to install
Heat pumps
These are devices for transferring thermal energy from a source to a coolant. The idea of a heat pump system itself is not new; it was proposed by Lord Kelvin back in 1852.
Operating principle: A geothermal heat pump extracts heat from environment and transfers it to the heating system. The systems can also work to cool buildings.
Working principle of a heat pump
There are open and closed cycle pumps. In the first case, the installations take water from an underground stream, transfer it to the heating system, remove thermal energy and return it to the point of collection. In the second, a coolant is pumped through special pipes 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 not connected to gas supply. Heat pumps They are complex and expensive to install, but they allow you to save on energy costs during operation.
The heat pump is designed to use environmental heat in heating systems
Solar collectors
Solar installations are systems for collecting thermal energy from the Sun and transferring it to a coolant
Water, oil or antifreeze can be used as a coolant. The design includes additional electric heaters that turn on if the efficiency of the solar installation decreases. There are two main types of collectors - flat and vacuum. The flat ones have an absorber with a transparent coating and thermal insulation. In vacuum systems, this coating is multi-layered; a vacuum is created in hermetically sealed collectors. 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 hot water supply and heating system of the house 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 that suit absolutely everyone. It is necessary to carefully weigh the pros and cons and take into account the characteristics of the building for which the system is selected. If in doubt, you should consult a specialist.
Video: types of heating systems
