Defense devices used in the combined heating system. Modern heating water heating devices

One after another on the planet is collapsed by economic crises, which together with a rapidly diminutive number of resources creates the need for the development and use of energy-saving technologies. This trend has not bypassed the heating system, seeking to preserve or even increase their efficiency with noticeably less resource consumption. We figure out that they are new technologies for the heating of a private house, apartments and industrial premises, decomposing the heating system into four main components: heat generator, heating device, heating system and control system.

The boiler system of heating is the most productive, albeit the most expensive (after electrical heaters) from all modern autonomous heating technologies. Although the melting itself is an invention with an ancient history, modern manufacturers managed to modernize it by increasing the efficiency and adapting to different types of fuel. So, there are three main (working on a stuff) type of boilers - solid fuel, gas, on liquid fuel. Several electrocurceptors knocking out of this classification, as well as combined, or multi-fuel - combine the quality of two or three varieties at once.

Solid fuel boilers

The tendency to return to the traditions of the past and active use of solid fuel are interesting: from ordinary firewood and coal to special pellets (granules compressable from the side products of woodworking) and peat briquettes.

Solid fuel boilers are divided by the type of fuel on:

Classic without problems "take" any type of hard fuel, as reliable as possible and simple (in fact, it is an oldest heat generator in the history of mankind), cheers. Of the disadvantages: "Capriciousness" with respect to wet fuel, low efficiency, the impossibility of adjusting the temperature of the coolant.

Pellet boiler is a heating device working on wood waste compressable in small granules. High efficiency is allocated, long-time long-time operation, an extremely convenient loading system for pellets (covered from the bag or package), the possibility of setting up the boiler. The only significant drawback is quite expensive granules for heating the price of which ranges from 6900 to 7700 rubles per ton, depending on ash content and calorificities.

The next type is the boilers of heating pyrolysis, working on pyrolysis gas extracted from wood. Fuel in such a boiler slowly tweets, and does not burn, thanks to which it gives noticeably more heat. Advantages: High efficiency and reliability, heat transfer adjustment, up to half-loading without re-loading. The only drawback is the need to connect to the power grid, which is why the house may remain without heat during interruptions with the power supply of electricity.

Standard long burning boilers are loaded by any kinds of solid fuel, except for wood: coke, brown and stone coal, peat briquettes, pellets. There is another variety designed specifically to work on firewood and a slightly different device. Advantages: work up to five days on petroleum products and up to two days when loading wood. Disadvantages: relatively low efficiency, the need for constant cleaning.

Gas boilers

The main gas is the most economical of all types of fuel, and boilers, on it working, are considered to be the most comfortable in use and maintenance. This is explained by their fully automated work and absolute security, for which many sensors and controllers are responsible. The disadvantages do not have, although they need a gas highway or permanent delivery of new cylinders.

Boilers on liquid fuel

It cannot be said that such innovative heating systems, but they are stably in demand for decades and therefore deserve mention. The main types of liquid fuel: diesel fuel and liquefied propane-butane mixture. Advantages over solid fuel: almost complete operation automation. Disadvantages: the extremely high cost of heating, inferior only with electricity.

Electric heating

It has a wide variety of heating systems and individual instruments. These are electroconverters (which, in turn, are in-depth, outdoor and walls), and electrocotes, and fan heaters, and infrared heaters, and oil radiators, and heat guns, and the well-known warm floor. Their overall and still irresistible drawback is an extremely high cost of heating. Infrared radiators and warm floors are considered the most economical.

Heat pumps

These heating systems are modern in the full sense of the word, despite the fact that they appeared in the 80s. Then they were only available only to wealthy people, but now many were adversely used to collect them manually, thanks to which slowly, but surely conquer popularity. A very simplistic principle of their work is to extract heat out of air, water or land outside the house and transfer it to the house where heat is transmitted or directly into the air, or first into the coolant - water.

Heliosystems

Another rapidly developing technology is the heating coleosystems, better known as solar cells.

Benefits:

Disadvantages:

Heat panels

Present thin rectangular (usually) plates fixing on the wall. The back side of such a plate is covered with a heat accumulating substance capable of heat up to 90 degrees and receiving heat from the heating element. Energy consumption is only 50 watts per square meter, in contrast to obsolete electrocamines that require at least 100 watts on the same area. Heating occurs due to the convection effect.

In addition to efficiency, the heat panels differ:

The disadvantage is only one - the heat panels become unprofitable in spring and early in the fall, when the dwelling only needs in a small heating from the evening in the morning.

Monolithic quartz modules

Unique development of S. Sargsyan - Candidate of Technical Sciences. Externally, the plates are very similar to the heat panels, however, the principle of their action is based on the high heat capacity of quartz sand. The heating element transmits the heat of thermal energy, after which it continues to heat the dwelling, even when the device is disabled from the network. Savings, as in the case of thermal panels, is 50% of the costs of standard electrical heaters.

PLEN - film rays electric heaters

In this innovative heating system, the device is as simple, however brilliantly: the power cable, heating elements, dielectric filth and reflecting screen. The heater is fixed on the ceiling, and the IR-radiation produced by it is heated below items. Those in turn transmit heat air.

The main advantages of PLEN:

Heat hydrodynamic pumps

These devices, also known as cavitation heat generators of heating systems, produce heat due to heat carrier heating on cavitation principle.

The coolant in such a pump rotates in a special activator.

In places of breaking the holistic mass of fluid as a result of an instantaneous pressure reduction, bubbles-cavities appear, almost instantly bursting. This causes a change in the physicochemical parameters of the coolant and the release of thermal energy.

Interestingly, even at the current level of scientific and technical development, the process of cavitation energy generation is poorly understood. An integral explanation why the energy increase is greater than its costs until it is found.

Air conditioning as heater

Almost all modern air conditioners are equipped with heating function. Oddly enough, the air conditioner has three times large efficiency than standard electrical heaters: 3 kW heat from 1 kW of electricity against 0.98 kW of heat from 1 kW electricity.

Thus, air conditioning for heating in winter is capable of replacing the disconnected heating or the electrocamine failed. However, due to the fact that in air conditioners for air heating are not used, their effectiveness falls with each degree of temperature outside the window. In addition, heavy frost overloads the device, and the work in this mode can lead to breakage. The best option will be the use of air conditioner in the off-season.

Convectors

Since the convector heating system - the concept is extremely wide, and almost every modern heating device uses a convection effect, we will mention in advance that it comes here only about individual water and electroconvectors. They are a ribbed heater placed in a metal case.

Air circulating air heats up and rises upwards, and air masses have been tightened in its place, which have already managed to cool down during this time.

This infinite circulation is called convection. By the source of heat, convector heaters are divided into water and electric, and at the location of the location - on intrapole, outdoor and wall mounted. Also, any of them can work on a principle or natural convection, or forced (with a fan).

Although the varieties of convectors and the features of each of them are the topic for a separate article, you can allocate the general advantages of using these heaters:

So what is more profitable financially?

As a result, we compare the cost of heating on different types of fuel: on firewood, peellet, stone coal, diesel fuel, propane-butane mixture, conventional main gas and electricity. At average prices for each type of fuel and with the average duration of the heating season at 7 months during this time will have to spend:

The leader is obvious.

Heating devices

First of all, the radiators of heating are modern - these are bimetallic and aluminum models. However, there is a stable demand for steel, and pig-iron products, which is due to the new approach of manufacturers to the manufacture of obsolete, seemingly heating devices. We will briefly describe the advantages and disadvantages of each type.

Aluminum

The most popular in the post-Soviet space for the price / quality ratio (cheaper than bimetallic, largely reliable steel and cast iron).

Benefits:

the best among all the analogues of the heat transfer;
expensive models 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

The best type of radiators is generally recognized. The name was obtained by combining steel (inner layer) and aluminum (casing).

Benefits:

Disadvantages: high price.

Steel

They are poorly suitable for multi-storey houses and a centralized heating system as a whole, and all their best properties show in private houses, perfectly fit into the system of heating of industrial premises at factories and factories. More details about steel heating radiators can be found.

Benefits:

heat transfer above average;
fast start of heat transfer;
low cost;
aesthetic look.

Disadvantages:

Cast iron

It should be understood that the heating radiators are modern cast iron - these are no longer bug and unveiled remnants of the past, "decorated" almost every home in the time of the USSR. Modern manufacturers have significantly improved their appearance by making almost indistinguishable from bimetallic or aluminum models. Moreover, the fashion is torn on the so-called, forms and patterns of which bring the atmosphere of the beginning of the XX century to the house.
Benefits:

Disadvantages: huge weight and resulting due to this complexity with the installation (often special feet supports are required).

Heating system

In most modern country houses, a horizontal heating system is used, the main difference of which is from the vertical wiring - partial (less often - complete) absence of vertical risers.

In Russia, such a kind of horizontal system is particularly popular as a single-wire heating system (or single-tube).

It suggests a natural, without circulation pump movement of water. From the heating device, the coolant comes on a riser on the second floor of the building, where it is distributed over radiators and transmitting risers.

Water circulation without a pump becomes possible due to the change in the density of hot and cold water.

A single-tube system has several advantages over two-pipe:

Control system

Additional benefits are able to provide the controller of the heating system - a miniature computer device that is capable of:

Types of heating devices are determined by their design due to the method of heat transfer (convective or radiation heat exchange) from the outer surface of the instruments into the room.

There are six main types of heating devices, radiators, panels, convectors, ribbed pipes, smooth-tube devices and calorificates.

By the nature of the outer surface, the heating devices can be smooth (radiators, panels, smooth-cutting devices) and a ribbed surface (convectors, ribbed pipes, calorifers).

According to the material from which heating devices are manufactured, metal, combined and non-metallic devices are distinguished.

Schemes of heating devices

a - radiator, b - panel, in - convector, E - ribbed pipe, D - smooth-tube device.

Metal devices are performed by cast iron (made of gray cast iron) and steel (made of sheet steel and steel pipes).

In combination devices, a concrete or ceramic array is used, in which steel or pig-iron heating elements (heating panels) are embedded, or finned steel pipes placed in non-metallic (for example, asbestos-cement) casing (convectors).

Non-metallic devices are concrete panels with close-up glass or plastic pipes or with voids without pipes, as well as porcelain and ceramic radiators.

Height all heating devices can be divided into high (more than 600 mm high), medium (400-600 mm) and low (<400 мм). Низкие приборы высотой менее 200 мм называются плинтусными.

Schemes of heating devices of five types are shown in the figure. Calorifer used primarily to heat the air in ventilation systems.

The radiator is customary to call the convective-radiation-type device consisting of separate columns - sections with circular or ellips-shaped channels. The radiator puts into the room by radiation about 25% of the total heat transmitted from the coolant, and is referred to as the radiator only by tradition.

The panel is a convective-radiation-type device with a relatively shaft depth, not having lumen on the front. The panel transmits a somewhat large radiation than the radiator, part of the heat flux, but only the ceiling panel can be attributed to the radiation-type devices (which gives a radiation of more than 50% of the total amount of heat).

The heating panel may have a smooth, slightly feather or wavy surface, column or coil canals for the coolant.

Convector - a convective type device consisting of two elements - a ribbed heater and casing. The convector transfers at least 75% of the total amount of heat into the room. The casing decorate the heater and helps to increase the rate of natural air convection in the outer surface of the heater. Convectors also include plinth heating devices without casing.

A ribbed pipe is called an openly installed heating device of a convective type, in which the area of \u200b\u200ban outer heat transfer surface is at least 9 times higher than the area of \u200b\u200bthe internal heat-visible.

Section of two-column radiator

hP - full height, HM - mounting (construction) height, L - depth; B - width.

The smooth-circuit is called a device consisting of several combined steel pipes, forming column channels (register) or a serpentine (serpentor) forms for a coolant.

Consider how the requirements for heating devices are performed.

1. Ceramic and porcelain radiators are usually manufactured in the form of blocks, differ in pleasant appearance, have a smooth, easily purified surface surface. Have sufficiently high heat engineering indicators: Kp p \u003d 9.5-10.5 W / (m 2 K); F E / F F\u003e 1 and reduced surface temperature in comparison with metal devices. When they are used, the consumption of metal in the heating system is reduced.

Ceramic and porcelain radiators have not been widespread due to insufficient strength, unreliability of compounds with pipes, difficulty manufacturing and installation, the possibility of penetrating water vapor through ceramic walls. They are used in low-rise construction, used as non-pressure heating devices.

2. Cast iron radiators - widely used heating devices - cast from gray cast iron in the form of individual sections and can be combined into devices of various areas by connecting sections on the nipples with gaskets from rubber heat-resistant. A variety of designs of single, two- and multilone radiators of different heights are known, but two-column medium and low radiators are most common.

Radiators are designed for the maximum operational (the term is usually used - working) the pressure of the coolant of 0.6 MPa (6 kgf / cm 2) and have relatively high heat engineering indicators: K PR \u003d 9.1-10.6 W / (M 2 K) and F E / F F ≤1.35.

However, the significant solid capacity of radiators [(m \u003d 0.29-0.36 W / (kg to) or 0.25-0.31 kcal / (h in kg ° C)] and other disadvantages cause them to replace them with lightest and less metal devices . It should be noted their unattractive view when the installation is open in modern buildings. In sanitary and hygienic terms, radiators, except for one-column, cannot be considered satisfying, since the cleaning of dust of the intersection space is sufficiently difficult.

The production of radiators is laborious, installation is difficult due to bulkness and significant mass of the assembled devices.

Resistance to corrosion, durability, layout advantages in good heat engineering indicators, production components contribute to the high level of radiators output in our country. Currently, a two-column cast iron radiator type M-140-AO with a depth of section 140 mm and an intercolent inclined fins, as well as the C-90 type with a depth of a 90 mm section of the section is 90 mm.

3. Steel panels differ from cast-iron radiators smaller mass and cost. Steel panels are designed for operating pressure to 0.6 MPa (6 kgf / cm2) and have high heat engineering indicators: K PR \u003d 10.5-11.5 W / (M 2 K) and F E / F F ≤1.7 .

The panels produce two structures: with horizontal collectors connected by vertical columns (column form), and with horizontal sequentially connected channels (co-form). The serpent is sometimes performed from the steel pipe and welded to the panel; The device in this case is called sheet-tube.

Panels satisfy architectural and construction requirements, especially in buildings from large building elements, are easily cleaned of dust, allow to mechanize their production using automation. On the same production areas, we may issue 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 are reduced during installation due to decreasing metal mass to 10 kg / m 2 ENP. Reducing the mass increases the thermal voltage of the metal to 0.55-0.8 W / (kg to). The propagation of steel panels is limited to the need to use high-quality cold-rolled sheet steel with a thickness of 1.2-1.5 mm, resistant to corrosion. In the manufacture of the usual sheet steel, the service life of the panels is reduced due to intense internal corrosion. Steel panels, except for sheet-tube, are used in heating systems with enclosed water.

Steel stamped panels and radiators of various designs are widely used abroad (in Finland, USA, Germany, etc.). In our country, medium and low steel panels are available with channel channels and a serpentine and paired (in depth) installation.

4. Concrete heating panels manufactures:

with promoted heating elements of the serpentine or column form from steel pipes with a diameter of 15 and 20 mm;
with concrete, glass or plastic channels of various configurations (bulk panels).

These devices are located in the enclosing room designs (combined panels) or attach them (dashboard panels).

When using steel heating elements, concrete heating panels can be used at operating pressure of the coolant to 1 MPa (10 kgf / cm 2).

Concrete panels have heat engineering indicators close to the indicators of other smooth appliances: K OD \u003d 7.5-11.5 W / (m 2 K) and F E / F ≈1, as well as high heat voltage. Panels, especially combined, respond to strict architectural, sanitary and hygienic and other requirements.

However, concrete panels, despite their compliance with most of the requirements for heating devices, are not widely distributed due to operational deficiencies (combined panels) and installation difficulties (dashboard panels).

5. Convectors have a relatively low heat engineering indicators K PR \u003d 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 there are convectors with steel heaters:

plinth convectors without casing (type 15 kp and 20 kp);
low convectors without casing (type "Progress", "Accord");
low convectors with a casing (type "Comfort").

The plinth convector of type 20 KP (15 kp) consists of a steel pipe with a diameter DY \u003d 20 mm (15 mm) and a closed finishment with a height of 90 (80) mm in a step of 20 mm, made of 0.5 mm thick steel, tightly planted on a pipe . Convectors 20 KP and 15 KP are produced in different lengths (after 0.25 m) and at the factory are combined into nodes consisting of several convectors (in length and height) connecting their pipes and regulating cranes.

It should be noted the advantage of the use of plinth convectors as an improvement in the thermal regime of the premises when they are placed in the lower zone along the length of the windows and the outer walls; In addition, they occupy little place in the depths of the premises (the construction depth is only 70 and 60 mm). Their disadvantages are: the cost of sheet steel, not efficiently used for heat transfer, and the difficulty of cleaning fins from dust. Although their vacuuming surface is small (less than that of radiators), they are still not recommended to be used for heating of premises with increased sanitary and hygienic requirements (in medical buildings and children's institutions).

A low progress convector is a modification of a convector 20 KP, based on two pipes connected by the general fins of the same configuration, but greater height.

The low accorder type convector also consists of two parallel steel pipes D y \u003d 20 mm, which consistently flows the coolant, and vertical elements of the fins (height 300 mm) from sheet steel with a thickness of 1 mm, placed on pipes with 20 mm gaps. Ords elements forming the so-called facial surface of the device have in terms of P-shaped (edge \u200b\u200bof 60 mm) and open to the wall.

The accorder type convector is made in different lengths and is installed in one and two rows in height.

In the convector with a casing, air mobility increases, contributing to an increase in the heat transfer of the device. The heat transfer convectors increases depending on the height of the housing.

Cover convectors are used mainly to heating the premises of public buildings.

Low convector with a skin type "Comfort" consists of a steel heating element, collapsible casing made of steel panels, an air duct grille and air regulation valve. In the heating element, the rectangular ribs are attached to two pipes D Y \u003d 15 or 20 mm in increments from 5 to 10 mm. The total mass of the heater metal is 5.5-7 kg / m 2 ENP.

The convector has a depth of 60-160 mm, is installed on the floor or on the wall and can be on the movement of the coolant through the passage (for the horizontal connection with another convector) and the terminal (with the Kalach).

The presence of a valve for air regulation allows you to connect convectors sequentially by heat carrier without installing fittings to regulate its quantity. Convectors can also be with artificial convection when installed in a special design fan casing.

6. Ribbed pipes are made of gray cast iron and are used at operating pressure to 0.6 MPa (6 kgf / cm 2). Flange pig-iron pipes have the greatest distribution, on the outer surface of which are fine ribbed round ribs.

The outer surface of the ribbed pipe due to the high coefficient of fins is many times more than the surface of the smooth pipe of the same diameter (the inner diameter of the ribbed pipe 70 mm) and length. The compactness of the device, the reduced temperature of the surface of the ribs when using a high-temperature coolant, comparative simplicity of manufacture and low cost, determine the use of this ineffective in the heat engineering of the device: K PR \u003d 4.7-5.8 W / (m 2 K); F E / F f \u003d 0.55-0.69. Its disadvantages also need to include unsatisfactory appearance, the small mechanical strength of the ribs and the difficulty of purification from dust. Ribbed pipes also have a very low thermal voltage indicator of the metal: M \u003d 0.25 W / (kg to).

They are used in industrial premises, in which there is no significant allocation of dust, and in the auxiliary premises with a temporary stay of people.

Currently, round ribbed pipes are available on a limited range with a length of 0.75 to 2 m for a horizontal installation. Style-profile ribbed pipes are being developed, to which the ribbed pipe of type PK with rectangular ribs is 70 x 130 mm. This pipe is characterized by ease of manufacture and relatively small mass. The base is the steel pipe D y \u003d 20 mm, poured into the cast-iron fins with a thickness of 3-4 mm. On top of the edges, two longitudinal plates stick to protect the main fins from mechanical damage. The device is designed for operating pressure to 1 MPa (10 kgf / cm 2).

Convector circuit with casing

1 - heating element, 2 - casing, 3 - air valve.

For the comparative heat engineering characteristics of the main heating, the table shows the heat transfer of devices with a length of 1 m.

Heat transmission of heating devices with a length of 1 m with Δt cf \u003d 64.5 ° and water flow 300 kg / h.

Heating devices	Depth of the device, mm	Heat transfer
Heating devices	Depth of the device, mm	W / M.	kcal / (h m)
Radiators:
- Type M-140-JSC	140	1942	1670
- type C-90	90	1448	1245
Steel panels type MZ-500:
- Single	18	864	743
- Sparna	78	1465	1260
CONVECTOR 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
Ribbed trumpet	175	865	744

As can be seen from the table, high heat transfer on 1 m lengths are the deeper heating devices; The greatest heat transfer has a cast-iron radiator, the smallest is a plinth convector.

7. Smooth-tube devices are performed from steel pipes in the form of coils (pipes are connected by the movement of the coolant sequentially, which increases its speed and 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 the pipe D Y \u003d 32-100 mm, located at a distance of one from another not less selectable diameter of pipes to reduce mutual irradiation and, accordingly, increasing heat transfer to the room. Smooth-tube devices are used at operating pressure to 1 MPa (10 kgf / cm 2). They have high heat engineering indicators: K PR \u003d 10.5-14 W / (m 2 K) and F E / F Φ ≤1.8, and the greatest values \u200b\u200brefer to smooth steel pipes with a diameter of 32 mm.

Indicators of heating devices of various types

iT	pressure	Requirements for appliances
		Technical				architectural Construction		sanitary hygienic		produce Mounting
											labor
Radiators:
Economic I.	2-4		>1	-	++	+	-	+	++	-	-
- cast iron	6		Up to 1.35	-	-	-	+	-	-	-	-
Panels:
- Steel	6		Up to 1.7	++	+	+	-	-	++	++	+
- concrete	10		~ 1	+	++	+	±	++	+	-	±

- Without casing
- With a casing	10		<1	±	+	±	±	+	-	++	+
	6			+	-	-	++	+	-	-	-
	10		Up to 1.8.	-	-	-	-	-	++	-	-
	8		>1	-	+	-	++	+	-	+	-

Note: Sign + marked execution, sign - failure to comply with the requirements for appliances; The ++ signs are noted indicators that determine the main advantage of this type of heating device.

The smooth-tube devices meet sanitary and hygienic requirements - their dust-cutting surface is small and easily cleaned.

The disadvantages of smooth-tube devices include their bulkness, due to the limited area of \u200b\u200bthe outer surface, the inconvenience of placing under the windows, an increase in the consumption of steel in the heating system. Given these disadvantages and adverse appearance, these devices are used in industrial premises, in which there is a significant allocation of dust, as well as in cases where devices of other species cannot be used. In the production premises they are often used to heate the light lamps.

8. Calorifers - compact heating devices of a significant area (from 10 to 70 m2) of an outer surface formed by several rows of finned pipes; Apply them for air heating of premises in local and central systems. Directly in the canorrifer premises are used as part of air-heating units of various types or for recycling air heaters. Calorifers are calculated on the working pressure of the coolant to 0.8 MPa (8 kgf / cm 2); Their coefficient of heat transfer depends on the speed of the water and air, therefore, it may vary widely from 9 to 35 and more W / (M 2 K) [from 8 to 30 and more kcal / (h m 2 ˚C)].

The table shows the indicators of heating devices of various types; Conditionally marked the execution or failure to comply with the requirements for instruments.

The heating of the room is impossible to imagine without heating devices presented in the market in a fairly wide type of diversity. In order to choose for yourself the most suitable option, you have to take into account a number of factors.

What are there

The classification of heating devices is carried out according to the following criteria:

Type of coolant. It may be liquid or gaseous.
Production material.
Specifications. This refers to dimensions, power, features of the installation and the presence of adjustable heating.

When choosing the optimal option, it is necessary to repel from the features of the heating system of the house and operational conditions. At the same time, the entire list of requirements and norms relating to the heating devices should be observed. Along with the capacity of products, the specificity of their installation is of great importance. In the absence of gas supply and the ability to arrange water heating, another option remains with electrical heaters.

Device of the water heating system

Water heating is the most common way of heating buildings. This explains the availability of a significant variety of varieties of heating devices for water contours. Causes are in a good level of the efficiency of these products, as well as reasonable costs for the purchase, installation and maintenance of maintenance. The designs of these heating devices are very similar to each other. The core of each of them is the cavity: it circulates hot water, the heating surface of the battery. Further, the convection process is entered into operation, which translates heat to the entire room.

Radiators for water heating systems can be made of the following materials:

Cast iron.
Become.
Aluminum.
Combinations of materials (so-called "bimetallic batteries").

Any of these types of heating devices has its own specifics. In each particular case, it is necessary to take into account the area of \u200b\u200bheated room, installation features, quality and type of coolant used (for example, in some cases antifreeze). To regulate battery power, it is possible to build or disconnect sections. It is desirable that the length of one radiator does not exceed 1.5-2 meters.

Batteries from cast iron

The cast iron type of heating devices belongs to the most common options for the configuration of domestic centralized systems. He was preferred to other varieties mainly due to cheapness. In the future, the instruments of this type have become gradually extended by devices with a higher heat transfer coefficient (it is only 40% in pig-iron batteries). Currently, the cast iron radiators are mostly equipped with an old sample system. As for modern interiors, they can meet designer cast iron models.

To the strengths of the device of heating devices, a significant surface area can be attributed through which the energy is transmitted from the coolant into the surrounding space. Another noticeable advantage is the durability of cast-iron batteries: they are able to serve without problems 50 or more. Disadvantages are also available, and they are quite a lot. First, the coolant is used in very large volumes (up to 1.5 liters per section). Heats the cast iron slowly, so you have to expect until after turning on the boiler, the warmth will begin to enter the room. It is not easy to repair such batteries, and to reduce the likelihood of breakdowns as much as possible, they have to be cleaned every 2-3 years. Installation work is intensified by the large weight of radiators.

Aluminum batteries

Aluminum devices are distinguished by very high heat transfer, which makes it possible to bring the power of one section to 200 W. This is quite enough for a full heating of 1.5-2 m 2 living space. The advantages of aluminum batteries include their cheapness and a small mass, which markedly simplifies assembly work. According to the duration of operation, aluminum devices are almost two times inferior to their cast-iron counterparts (they can serve no more than 25 years).

Bimetallic batteries

The strength of bimetallic structures are special convection panels that contribute to an increase in the quality of air flow circulation. In addition, the instruments of this type can be equipped with special regulators, with which you can increase or decrease the coolant consumption. Installation work in its simplicity resemble the installation of aluminum radiators. Each of the sections has a capacity of 180 W, providing heating of 1.5 m 2 area.

In some cases, the use of water type of heating is found with serious difficulties. For example, bimetallic radiators cannot be installed in systems where antifreeze is used as a coolant. These non-freezing fluids that protect pipes from the size are able to have a destructive effect on the interior of the batteries. You should also take into account the high cost of this option of heating.

Electrical types of heaters

In cases where problems arise with water heating organizing, it is customary to use electrical heaters. They are also represented by several varieties, differing from each other with power and the method of heat recoil. The most significant disadvantage of household heating devices of this kind are the high costs of electricity consumed. In this case, it is often required to lay a new wiring, designed for increased loads. If the total capacity of all electrical heaters exceeds 12 kW, technical norms provide for the organization of a network with a voltage of 380 V.

Convection type of heating devices

For electrical heaters of convection type, the ability to heat the room at high speed, which is facilitated by circulating heat air flows. The lower part of the devices is equipped with special holes for suction of air flows, for heating of which thes are used (warm air leaves through the upper notch). The power of modern heating devices of this type ranges from 0.25-2.5 kW.

Oil radiators

In the operation of oil electric heaters, the principle of convection also applies. Inside the device is poured special oil for heating by ane. To adjust the heating, the thermostat that turns off the power to achieve the desired temperature mark is often used. Oil devices are distinguished by high inertia. This is manifested in slow warming up the device and in the same slow cooled after the cessation of electricity supply.

The surface temperature is usually heated to 110-150 degrees, which provides for compliance with safety rules. Such a device is prohibited to establish in principle to marked surfaces. Oil radiators are equipped with a convenient adjustment of the heating intensity designed for 2-4 modes of operation. Holding in memory the power of one section (150-250 kW), choose the optimal model for heating a particular room is not entirely difficult. The maximum power of such a device is limited to 4.5 kW.

Infrared heating

The choice of infrared type heating devices brings the following dividends:

Electricity savings up to 30%, if compared with conventional electrical appliances.
Oxygen in the air does not burn.
The room is heated in a matter of minutes.

Classify infrared devices by way of broadcasting waves. In new heating devices, radiation transmission into the surrounding space is carried out due to resistor conductors installed on a special film. The power of warm mats can reach 800 W / m 2. Film heaters are convenient because with their help you can organize warm floors.

As for carbon emitters, the waves are emitted with spirals from a hermetic transparent flask. The power of such devices is within 0.7-4.0 kW. The power of carbon heaters is an order of magnitude higher, which provides for more stringent fire safety measures.

Heated gas

In order to save finance, gas heaters can be used. The simplest variety of them is a gas convector, which commutes to a trunk gas pipeline or a cylinder with liquefied propane. The burner of the device is fully protected from contact with the surrounding atmosphere: for supplying oxygen in this case, a special tube is used, which is removed on the street through a hole in the wall. For these devices, high power is characterized (at least 8 kW) and low cost of operation. Among the weaknesses of gas heaters, it is possible to identify the obligation to record in the controlling agencies, the need for effective ventilation and the need for regular cleaning of nozzles.

One of the main elevations of water heating systems is the heating device - it is appointed for heat transfer from heat carriers to the heated room.

To maintain the required room temperature, it is required that at each moment of the heat loss of the room of the room, the heat transfer was covered with the heating device of the QPP and the QTP pipes.

The heat transfer diagram of the heating device QPP and pipes for compensation for the heat loss of the room of quantity and the QDOC with the heat transfer of the QT from the water coolant is shown in Fig. 24.

Fig. 24. The heat transfer scheme of the heating device located at the external fencing of the building

The heat of the QT, which caused by the heat carrier for heating this room, should be larger than the heat loss quantity by the amount of additional heat loss of the QDET of the building structures caused by the enhanced warming construction structures.

Qt \u003d qu) + qdop

The heating device is characterized by the heating surface of the FPP, M2, calculated to provide the required heat transfer of the device.

The heating devices on the predominant method of heat transfer are divided into radiation (ceiling emitters), convective radiation (appliances with a smooth outer surface) and convective (convectors with a ribbed surface).

When heating the premises with ceiling emitters (Fig. 25), heating is carried out mainly due to the radial heat exchange between heating radiators (heating panels) and the surface of building construction designs.

Fig. 25. Suspended metal heating panel: A - flat-screen; b - with a wave-shaped screen; 1 - warm pipes; 2 - visor; 3 - flat screen; 4 - thermal insulation; 5 - wave-like screen

Radiation from the heated panel, falling on the surface of fences and objects, is partially absorbed, partially reflected. At the same time, the so-called secondary radiation occurs, also in the end absorbed by objects and places of the room.

Thanks to the radiant heat exchange, the temperature of the inner surface of the fences is increased compared with the temperature under convective heating, and the surface temperature of the internal fences in most cases exceeds the air temperature of the room.

With panel-radiant heating, due to the increase in the temperature of the surfaces in the room, a situation is favorable for humans. It is known that human well-being is significantly improved by increasing the proportion of convective heat transfer in the overall heat transfer of its body and reduce radiation on cold surfaces (radiation cooling). This is just ensured with radiant heating, when the human heat transfer by radiation decreases due to the increase in the surface temperature of the fences.

With panel-radiant heating, a decrease in the usual (regulatory for convective heating) air temperature in the room (on average 1-3 ° C), and therefore the convective heat transfer of man is even more increasing. It also contributes to the improvement of human well-being. It has been established that under normal conditions, well-being of people is ensured at an indoor air temperature in a room of 17.4 ° C with wall heating panels and at 19.3 ° C under convective heating. From here it is possible to reduce the consumption of thermal energy to the heating of premises.

Among the shortcomings of the panel-radiant heating system should be noted:

Some additional increase in heat loss through external fences in those places where heating elements are embedded; -

The need for special reinforcement for individual regulation of heat transfer of concrete panels;

Significant thermal inertia of these panels.

Instruments with a smooth outer surface are sectional radiators, panel radiators, smooth-tube devices.

Appliances with a ribbed heating surface - convectors, ribbed pipes (Fig. 26).

Fig. 26. Schemes of heating devices of various types (transverse section): A - sectional radiator; b - steel panel radiator; B - a smooth-tube device of three pipes; g - convector with a casing; D - device from two ribbed pipes: 1 - channel for the coolant; 2 - plate; 3 - Rib

According to the material from which heating devices are manufactured, metal, combined and non-metallic devices are distinguished. Metal devices are performed mainly of gray cast iron and steel (sheet steel and steel pipes). Copper pipes, leaf and cast aluminum and other metals are also used.

In combination devices, heat-conducting material (concrete, ceramics, etc.) are used, which close up steel or pig-iron heating elements (panel radiators) or finned metal pipes, placed and non-metallic (such as asbestosptpy) casing (convectors).

Non-metallic devices include concrete panel radiators with extended plastic or glass pipes, or with voids, as well as ceramic, plastic and other radiators.

In height, all heating devices are divided into high (over 650 mm high), medium (more than 400 to 650 mm), low (more than 200 to 400 mm) and plinth (up to 200 mm).

The magnitude of the thermal inertia can be allocated with low and large inertia devices. Minority devices have a small mass and accommodate a small amount of water. Such devices made on the basis of metal pipes of small cross section (for example, convectors) quickly change the heat transfer to the room when adjusting the amount of the coolant admiss in the device. Devices having a greater thermal inertia are massive, which accommodate a significant amount of water (for example, concrete or sectional radiators), the heat transfer is changed slowly.

For heating devices, in addition to economic, architectural and construction, sanitary and hygienic and production and installation requirements, still heat engineering requirements are added. The device requires the transfer from the coolant through the unit of the area to the room of the largest heat flux. To fulfill this requirement, the device must have an increased value of the CPR heat transfer coefficient, compared with the value of one of the types of sectional radiators, which is adopted for the standard (cast iron radiator type N-136).

In tab. 20 The heat engineering indicators and symbols are noted other instruments indicators. The positive indicators of the instruments are noted in Plus, the minus sign is negative. Two pluses indicate indicators that determine the main advantage of any type of appliances.

Table 20.

Design of heating devices

The radiator is called a convective-radiation-type convection device, consisting of separate columns - sections with circular or ellipse channels. Such a radiator puts into a radiation room about 25% of the total heat flux transmitted from the coolant (the remaining 75% convection) and is referred to as the "radiator" only by tradition.

The radiator sections are cast from gray cast iron, they can be combined into devices of various areas. Sections are connected on nipples with pads from cardboard, rubber or paronite.

A variety of designs of single, two-, and multiscolone sections of different heights are known, but two-column sections (Fig. 27) of the average (mounting height Hm \u003d 500 mm) radiators are most common.

Fig. 27. Two-column radiator section: HP - full height; HM - mounting height (construction); B - Construction Depth

The production of cast iron radiators is laborious, the installation is difficult due to the bulky and significant mass of the assembled devices. Radiators cannot be considered satisfying sanitary and hygienic requirements, since the purification of the dust of the intersection space is complex. These devices have significant thermal inertia. Finally, it should be noted the inconsistency of their appearance of the interior of the premises in the buildings of modern architecture. These disadvantages of radiators cause the need to replace them with lighter and less metal appliances. Despite this cast iron radiators, this is the most common heating device.

Currently, the industry produces cast-iron sectional radiators with a construction depth of 90mm and 140 mm (type "Moscow" - abbreviated M, such as Istartardti - MS and others). In fig. 28 shows the designs of produced cast iron radiators.

Fig. 28. Cast iron radiators: A - M-140-JSC (M-140-AO-300); b - M-140; B - RD-90

All cast iron radiators are designed for working pressure up to 6 kgf / cm2. The meters of the heating surface of the heating appliances are the physical indicator - the square meter of the heating surface and the heat engineering indicator is an equivalent square meter (ECM2). An equivalent square meter is called the area of \u200b\u200bthe heating device, which gives 1 hour 435 of the heat kcal with the difference in the average temperature of the coolant and air 64.5 ° C and the water flow in this device is 17.4 kg / hour according to the coolant movement scheme from top to bottom.

Technical characteristics of radiators are shown in Table. 21.
The surface of the heating of pig-iron radiators and ribbed pipes
Table 21.

Continuation of table. 21.

Steel panel radiators consist of two selected sheets forming horizontal collectors connected by vertical columns (column form), or horizontal parallel and successively connected channels (serpentine form). The serpent can be made of steel pipe and weld to one profiled steel sheet; Such a device is called sheet-tube.

Fig. 29. Cast iron radiators

Fig. 30. Cast iron radiators

Fig. 31. Cast iron radiators

Fig. 32. Cast iron radiators

Fig. 33. Cast iron radiators

Fig. 34. Channel diagrams for coolant in panel radiators: a - column form; b - serpentine two-way, in - serpentine four-way

Steel panel radiators differ from cast-iron smaller mass and thermal inertia. With a decrease in the mass of approximately 2.5 times the heat transfer indicator is no worse than that of cast-iron radiators. Their appearance satisfies architectural and building requirements, steel panels are easily cleaned of dust.

Steel panel radiators have a relatively small area of \u200b\u200bthe heating surface, which is why it sometimes has to be resorted to the installation of panel radiators in pairs (in two rows at a distance of 40 mm).

In tab. 22 shows the characteristics of the produced steel stamped radiator panels.

Table 22.

Continuation of table. 22.

Concrete panel radiators (heating panels) (Fig. 35) may have concreted heating elements of the serpentine or register form from steel pipes with a diameter of 15-20 mm, as well as concrete, glass or plastic channels of various configurations.

Fig. 35. Concrete heating panel

Concrete panels have a heat transfer coefficient close to the indicators of other devices with a smooth surface, as well as high thermal voltage of metal. Devices, especially combined type, meet strict sanitary and hygienic, architectural and other requirements. The disadvantages of combined concrete panels include repair difficulties, a large thermal inertia complicating the control of the heat supply to the room. The disadvantages of the instruments of the filter type are the increased costs of manual labor during their manufacture and installation, reducing the useful area of \u200b\u200bthe floor of the room. Heat loss is also increasing through the additionally heated outdoor fences of buildings.

The smooth-circuit is called the device from several combined steel pipes that form channels for coolant coolant or register form (Fig. 36).

Fig. 36. Forms of the connection of steel pipes into smooth-tube heating instruments: A - coil form; B - Register form: 1 - thread; 2 - column

In the coil coating, the pipes are connected in series towards the movement of the coolant, which increases the speed of its movement and the hydraulic resistance of the device. With parallel connection of pipes in the register, the flow of the coolant is divided, the speed of its movement and the hydraulic resistance of the device decreases.

The devices are welded from pipes DB \u003d 32-100 mm, located apart from each other at a distance of 50 mm above their diameter, which reduces mutual irradiation and, accordingly, increases the heat transfer to the room. The smooth-tube appliances have the highest heat transfer coefficient, their vacuum surface is small and they are easily cleaned.

At the same time, smooth-paper devices are heavy and cumbersome, there are a lot of space, increase the consumption of steel in heating systems, have an unattractive appearance. They are used in rare cases when devices of other species cannot be used (for example, for heat heating).

The characteristics of smooth-paper registers are shown in Table. 23.

Table 23.

Convector is a convective type device consisting of two elements - a ribbed heater and the casing (Fig. 37).

Fig. 37. Convectors schemes: A - with a casing; B - without casing: 1 - heating element; 2 - casing; 3 - air valve; 4 - pipe fins

The casing decorate the heater and helps to increase heat transfer due to an increase in air mobility at the heater surface. The convector with the casing transmits to the room by convection to 90-95% of the entire heat flux (Table 24).

Table 24.

The device in which the functions of the casing performs the root of the heater, is called convector without casing. The heater is performed from steel, cast iron, aluminum and other metals, casing - from sheet materials (steel, asbestos cement, etc.)

Convectors have a relatively low heat transfer coefficient. Nevertheless, they are widely used. This is explained by the simplicity of manufacturing, installation and operation, as well as low metal.

The main technical characteristics of the convectors are shown in Table. 25

Table 25.

Continuation of table. 25.

Note: 1. When a multi-row installation of plinning convectors, the KP introduces the correction to the heating surface depending on the number of rows vertically and horizontally: with a two-row installation vertical 0.97, three-row - 0.94, four-row - 0.91; For two rows horizontally, the amendment is 0.97. 2. Indicators of end and passing convectors models are the same. The passing convectors have an index A (for example NN-5A, H-7A).

The ribbed pipe is called a convective type device, which is a flange cast-iron pipe, the outer surface of which is coated jointly cast thin ribs (Fig. 33).

The area of \u200b\u200bthe outer surface of the ribbed pipe is many times larger than the surface area of \u200b\u200ba smooth pipe of the same diameter and length. This gives the heating device a special compactness. In addition, the reduced surface temperature of the ribs when using a high-temperature coolant, a comparative simplicity of manufacturing and low costs cause the use of this ineffective heat-effectively, a heavy device. The disadvantages of ribbed pipes include an irrelevated appearance, low mechanical strength of the ribs and the difficulty of purification from dust. Ribbed pipes are used as a rule in auxiliary premises (boiler houses, warehouses, garages, etc.). Industry produces round ribbed cast iron pipes with a length of 1-2m. They are installed horizontally into several tiers and are connected along a coating scheme on bolts using "Kalach" - flange cast-iron double taps and counter flanges.

For the comparative heat engineering characteristics of the main heating devices in Table. 25 shows the relative heat transfer of instruments with a length of 1.0 m in equal heat-hydraulic conditions when used as a heat carrier-water (heat transfer of the cast-iron sectional radiator 140 mm depth of 100%).

As can be seen, sectional radiators and convectors with a casing are distinguished by high heat transfer 1.0 m; The smallest heat transfer has convectors without casing and especially single smooth pipes.

Relative heat transfer of heating devices 1.0 m long Table 26

Selection and placement of heating devices

When choosing a type and type of heating device, the appointment, architectural layout and features of the thermal regime of the room, the place and duration of the people's stay, the type of heating system, technical and economic and sanitary and hygienic indicators of the device are taken into account.

Fig. 38. Cast iron ribbed tube with round ribs: 1 - channel for the coolant; 2 - ribs; 3 - flange

To create a favorable thermal regime, instruments are chosen, providing uniform heating of the premises.

Metal heating devices are installed mainly under light openings, and under the windows, the length of the device is desirable at least 50-75% of the opening of the opening, under the windows and stained glass, the devices are placed along their entire length. When the instruments are placed under the windows (Fig. 39a), the vertical axes of the instrument and the window opening should be the coincidence (no more than 50mm is allowed).

The devices located in the outer fences contribute to the increase in the temperature of the inner surface at the bottom of the outer wall and the window, which reduces the radiation cooling of people. The ascending flows of warm air, created by the instruments, prevent (if there are no windowsides, overlapping devices), enter the cooled air into the working area (Fig. 40a). In the southern regions with a short warm winter, as well as with a short stay of people, the heating devices are permissible to install in the inner walls of the rooms (Fig. 39b). At the same time, the number of risers and the length of thermal conductors is reduced and heat transfer of the instruments (approximately 7-9%), but the movement of the air with a reduced temperature near the floor of the room (Fig. 40B) occurs.

Fig. 39. Placement of heating devices in rooms (plans): A - under the windows; b - in the inner walls; P - heating device

Fig. 40. Air circulation circuits in rooms (cuts) with different arrangements of heating devices: A-under windows without windowsill; b - under windows with a windowsill in - in the inner wall; P - heating device

Fig. 41. Location under the window of the room of the heating device: a - long and low (preferably); b - high and short (undesirable)

Vertical heating devices are installed possible closer to the floor of the premises. With a significant rise in the device over the floor level of air at the floor surface, it can be transferred, since the circulation flows of heated air, closing at the level of the instrument, do not capture and do not warm the lower part of the room in this case.

The lower and the longer heating device (Fig. 41a), the smaller the temperature of the room and the entire air volume is better heated. The tall and short device (Fig. 41b) causes an active lifting of a jet of warm air, which leads to overheating of the upper area of \u200b\u200bthe room and lowering the cooled air along both sides of such a device into the working area.

The ability of a high heating device to cause an active ascending flow of warm air can be used to heating the premises of an increased height.

Vertical metal devices, as a rule, placed openly at the wall. However, it is possible to install them under the windowsides, in wall niches, with a special fence and decoration. In fig. 42 shows several techniques for installing heating devices in rooms.

Fig. 42. Placement of heating devices - A - in a decorative cabinet; b - in deep niche; in - in special shelter; g - behind the shield; d - in two tiers

The shelter of 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 with its open installation in a deaf wall. To transfer to the premises of a given heat flux, the area of \u200b\u200bthe heating surface of such an appliance should be increased by 12%. The placement of the device in the deep open niche (Fig. 42b) or one over the other in two tiers (Fig. 42d) reduces heat transfer by 5%. However, the hidden installation of instruments in which heat transfer does not change (Fig. 42B) or even increases by 10% (Fig. 42g). In these cases, it is not necessary to increase the area of \u200b\u200bthe heating surface of the device or even can be reduced.

Calculation of the area, size and number of heating devices

The area of \u200b\u200bthe heat pumping surface of the heating device is determined depending on the adopted type of the device, its location in the room and the joining diagram to the pipes. In residential premises, the number of instruments, and therefore, the necessary heat transfer of each device is set, as a rule, according to the number of window openings. In the angular premises add another device placed in a deaf end wall.

The calculation task is primarily in the determination of the area of \u200b\u200bthe outer heating surface of the device, which provides the necessary thermal flow from the coolant to the room in the calculated conditions. Then, according to the device catalog, based on the calculated area, the nearest trading size of the device is selected (the number of sections or the radiator brand (the length of the convector or ribbed pipe). The number of sections of pig-iron radiators is determined by the formula: N \u003d fpb4 / f1b3;

where F1- area of \u200b\u200bone section, m2; type of radiator adopted to installation indoor; B4 is a correction coefficient that takes into account the method of installing the radiator indoors; B3 - correction coefficient that takes into account the number of sections in one radiator and is calculated by the formula: b3 \u003d 0.97 + 0.06 / FP;

where Fp is the calculated area of \u200b\u200bthe heating device, m2.

The heating devices can be safely called the crown of the entire heating system. Without them, any water heating loses all practical meaning. In this article we will tell about how they are classified and what advantages have the most common types of heating devices. So, let's begin!

The first type of classification is according to the method of heat transfer.

There are 3 methods of heat transfer from the heating device of the environment:

radiation (radiation),
convection (direct heating of air)
radiation convective (combined) method.

Heat transmission by radiation. Also called radiant heat transfer. Any heated body emits infrared (radiation) rays, which moved perpendicular to the radiation surface, increase the temperature of the bodies to which fall, without increasing the air temperature. Further, the bodies that make radiation radiation themselves become warmer and begin to produce infrared rays, heating surrounding items. And so happens in a circle. In this case, the temperature at different points of the room remains the same. Interesting is the fact that radiation (infrared) radiation is perceived by our body as heat and does not harm our body at all, providing him, according to physicians, even positive effects. Radiation heating devices (radiators) were made to consider those devices that betray more than 50% heat into the environment with radiant. Such devices include different kinds of infrared heaters, "warm floors", sectional cast iron and tubular radiators, separate patterns of panel radiators and wall panels.

Transmission of heat convection. The convective method of heat transfer looks completely different. The air warms up from contact with the hotter surfaces of convection heating devices (convectors). The heated amount of air rises to the ceiling of the room due to the fact that it becomes easier than cold air masses. The next amount of air rises to the ceiling after the first and so on. Thus, we have a constant circular circulation of air masses "from the radiator to the ceiling" and "from the floor to the radiator." As a result, there is a feeling, familiar to the inhabitants of the premises of the heated convector - at the level of the head air can be warm, and in the legs there is a feeling of cold. Convective devices are customary to call heating devices exercising a convection of at least 75% of heat from the total volume. Convectors include tubular and lamellar convectors, ribbed pipes and steel panel heaters. The convective convective method of heat transfer.

The radiation-convective or combined method of heat transfer includes both types of heat transfer described above. They possess the devices that have been heat in the environment by a convective method by 50-75% of the total amount of heat transfer. Panel, as well as sectional radiators, floor panels, smooth-tube devices are counted to radiation-convective heating devices.

The second type of classification is the material from which the heating devices are made.

Here we are dealing with 3 groups of materials:

metals,
non-metals
combined.

Metal heaters include steel, cast iron, aluminum or copper heaters, as well as possible combinations of two of the listed metals (bimetallic heating devices).

Non-metallic heating devices - a rare phenomenon in the household heating goods market. In the manufacture of such devices, glass is almost always used.

To the class of combined heating devices, panel radiators (consist of an external concrete or ceramic insulating layer and inner metal - steel or cast iron heating elements) and convectors (metal pipes with ribs located in an additional metallic casing).

The third method of separating heating devices - according to the degree of thermal inertia.

In this case, thermal inertia is the residual heat transfer of the room after disconnecting the heating device. Thermal inertia may be small or large (depending on the diameter of pipes and specific types of heating devices).

The last method of classifying thermal devices - by its linear dimensions (meaning height and depth).

Since the dimensions often depend on the specific model and local requirements for the heating of the room, describe this method of classification does not make sense.

Conclusion

In this article, some of the concepts describing how heat transfer works were considered. In addition, standard ways of classifying the main types of heating devices present in the domestic heating equipment market were presented. We hope you have found something interesting in this article for yourself. We are glad to be useful!

If you want to learn more about the characteristics of the main types of heating devices - we strongly recommend reading the cycle of articles "The main thing about heating devices" on our website!