The heating system uses heating devices that serve to transfer heat to the room. Manufactured heating devices must meet the following requirements:
- Economic: low cost of the device and low material consumption.
- Architectural and construction: the device must be compact and match the interior of the room.
- Production and installation: mechanical strength of the product and mechanization in the manufacture of the device.
- Sanitary and hygienic: low temperature surfaces, small horizontal surface area, ease of cleaning surfaces.
- Thermal engineering: maximum heat transfer into the room and heat transfer control.
Classification of devices
The following indicators are distinguished when classifying heating devices:
- — the magnitude of thermal inertia (large and small inertia);
- - material used in manufacturing (metallic, non-metallic and combined);
- — method of heat transfer (convective, convective-radiative and radiation).
Radiation devices include:
- ceiling radiators;
- sectional cast iron radiators;
- tubular radiators.
Convective-radiation devices include:
- floor heating panels;
- sectional and panel radiators;
- smooth-tube devices.
Convective devices include:
- panel radiators;
- finned tubes;
- plate convectors;
- tubular convectors.
Let's consider the most applicable types of heating devices.
Aluminum sectional radiators
Advantages
- high efficiency;
- light weight;
- ease of installation of radiators;
- effective work heating element.
Flaws
- 1. not suitable for use in old heating systems, since salts heavy metals destroy the protective polymer film of the aluminum surface.
- 2. Long-term operation leads to the unsuitability of the cast structure and to rupture.
Mainly used in central heating systems. Operating pressure of radiators from 6 to 16 bar. Note that heaviest loads withstand radiators that were cast under pressure.
Bimetallic models
Advantages
- light weight;
- high efficiency;
- possibility of quick installation;
- heat large areas;
- withstand pressure up to 25 bar.
Flaws
- have a complex structure.
These radiators will last longer than others. Radiators are made of steel, copper and aluminum. Aluminum material conducts heat well.
Cast iron heating devices
Advantages
- not subject to corrosion;
- transfer heat well;
- withstand high pressure;
- it is possible to add sections;
- The quality of the coolant does not matter.
Flaws
- significant weight (one section weighs 5 kg);
- fragility of thin cast iron.
The operating temperature of the coolant (water) reaches 130°C. Cast iron heating devices last quite a long time, about 40 years. Heat transfer rates are not affected by mineral deposits inside the sections.
There is a wide variety of cast iron radiators: single-channel, two-channel, three-channel, embossed, classic, enlarged and standard.
In our country, the economical version of cast iron appliances has received the greatest use.
Steel panel radiators
Advantages
- increased heat transfer;
- low pressure;
- easy cleaning;
- simple installation of radiators;
- light weight compared to cast iron.
Flaws
- high pressure;
- metal corrosion, in the case of using ordinary steel.
Today, a steel radiator heats up better than a cast iron one.
Steel heating appliances have built-in thermostats that provide constant temperature control. The design of the device has thin walls and responds fairly quickly to the thermostat. Discreet brackets allow you to mount the radiator on the floor or wall.
The low pressure of steel panels (9 bar) does not allow them to be connected to a central heating system with frequent and significant overloads.
Steel tubular radiators
Advantages
- high heat transfer;
- mechanical strength;
- aesthetic appearance for interiors.
Flaws
- high price.
Tubular radiators are quite often used in room design because they add beauty to the room.
Due to corrosion, ordinary steel radiators are not currently produced. If you subject the steel to anti-corrosion treatment, this will significantly increase the cost of the device.
The radiator is made of galvanized steel and is not subject to corrosion. It has the ability to withstand pressure of 12 bar. This type of radiator is often installed in multi-storey buildings. residential buildings or organizations.
Heating devices of convector type
Advantages
- low inertia;
- small mass.
Flaws
- low heat transfer;
- high requirements for coolant.
Convector-type appliances heat the room quickly enough. They have several manufacturing options: in the form of a plinth, in the form of a wall block and in the form of a bench. There are also in-floor convectors.
This heating device uses a copper tube. The coolant moves along it. The tube is used as an air stimulator (hot air rises to the top, and cold air goes down). The air change process takes place in a metal box, which does not heat up.
Convector-type heating devices are suitable for rooms with low windows. Warm air from a convector installed near a window prevents cold air from entering.
Heating devices can be connected to centralized system, since it is designed for a pressure of 10 bar.
Heated towel rails
Advantages
- variety of shapes and colors;
- high pressure levels (16 bar).
Flaws
- may not perform its functions due to seasonal interruptions in water supply.
Steel, copper and brass are used as manufacturing materials.
Heated towel rails are available in electric, water and combined types. Electric ones are not as economical as water ones, but they allow buyers not to depend on the availability of water supply. Combined heated towel rails must not be used if there is no water in the system.
Radiator selection
When choosing a radiator, you need to pay attention to the practicality of the heating element. Next, you need to remember the following characteristics:
- overall dimensions of the device;
- power (per 10 m2 area 1 kW);
- operating pressure(from 6 bar - for closed systems, from 10 bar for central systems);
- acid characteristics water as a coolant (this coolant is not suitable for aluminum radiators).
After clarifying the basic parameters, you can proceed to the selection of heating devices based on aesthetic indicators and the possibility of its modernization.
Heating devices can be safely called the crown of any heating system. Any without them water heating loses all practical meaning. In this article we will talk about how the most common types of heating devices are classified and what advantages they have. So, let's begin!
The first type of classification is based on the method of heat transfer.
There are 3 ways to transfer heat from a heating device to the environment:
- radiation (radiation),
- convection (direct air heating)
- radiation-convective (combined) method.
Heat transfer by radiation. Also called radiant heat transfer. Any heated body emits infrared (radiation) rays, which, moving perpendicular to the surface of the radiation, increase the temperature of the bodies on which they fall, without increasing the air temperature. Further, bodies that receive radiation themselves become warmer and begin to produce infrared rays, heating surrounding objects. And so it goes in circles. At the same time, the temperature at different points in the room remains the same. An interesting fact is that radiation (infrared) radiation is perceived by our body as heat and does not harm our body at all, having, according to doctors, even positive effects on it. It was agreed that radiant heating devices (radiators) are those devices that are exposed to environment more than 50% of the heat is radiant. Such devices include various kinds infrared heaters, “warm floors”, sectional cast iron and tubular radiators, individual models of panel radiators and wall panels.
Heat transfer by 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 volume of air rises to the ceiling of the room due to the fact that it becomes lighter than colder air masses. The next volume 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, a feeling arises that is familiar to the inhabitants of rooms heated by a convector - at the level of the head the air can be warm, but a feeling of cold is felt in the legs. Convective devices are usually called heating devices that produce at least 75% of the heat from the total volume by convection. Convectors include tubular and plate convectors, finned tubes and steel panel heaters. Radiation-convection method of heat transfer.
The radiation-convective or combined method of heat transfer includes both types of heat transfer described above. They are equipped with devices that release heat into the environment by convection by 50-75% of the total amount of heat transfer carried out. Radiation-convective heating devices include panel and sectional radiators, floor panels, and smooth-tube devices.
The second type of classification is based on 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 heaters made of steel, cast iron, aluminum or copper, as well as possible combinations of two of these metals (bimetallic heating devices).
Non-metallic heating devices are a rare phenomenon on the market of household heating products. Glass is almost always used in the production of such devices.
The class of combined heating devices typically includes panel radiators (consisting of an external concrete or ceramic insulating layer and an internal metal - steel or cast iron heating elements) and convectors (metal pipes with fins, located in an additional metal casing).
The third way to divide heating devices is by the degree of thermal inertia.
IN in this case Thermal inertia is the residual heat transfer to the room after the heating device is turned off. Thermal inertia can be small or large (depending on the diameter of the pipes and specific types of heating devices).
The last way to classify thermal appliances is by their linear dimensions (meaning height and depth).
Since dimensions often depend on specific model and local requirements for space heating, it makes no sense to describe this method of classification.
Conclusion
IN this article Some of the concepts that describe how heat transfer works were reviewed. In addition, standard methods for classifying the main types of heating devices present on the domestic market were given heating equipment. We hope you found something interesting for yourself in this article. 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 series of articles “The main things about heating devices” on our website!
A heating device operating on the radiation-convective principle is called a radiator. The hollow design of the housing allows, by passing any coolant, to heat the outer surface of the metal device. And then from the sections of the heated radiator thermal energy radiated into the room.
Heat exchangers intended for heating indoor air are made of various alloys. This approach ensures maximum heat transfer rates in each specific case:
Aluminum appliances and their modifications, due to their high heat transfer, are in demand in individual construction, with gentle operating modes and careful preparation of the coolant.
Cast iron radiators, familiar to most Russians, represent an economical option for heating systems where it is impossible to monitor the quality of the water.
Copper tubes with aluminum fins are the heating element of all convector water systems.
Steel radiators, due to their wide range of types, are the most popular option among consumers who follow fashionable foreign trends in interior design.
Aluminum sectional radiators
Radiators from aluminum alloys They stand out due to their low weight and high efficiency. These factors are due to: simple installation and efficient operation of the heating element.
Declared by manufacturers as devices intended for use in central heating systems, they are not always suitable for use in old-style heating circuits, because heavy metal salts can destroy the polymer film covering the aluminum surface. This process continues long time, as a result, leads to rupture of the cast structure.
Provided that the coolant is controlled (using an autonomous heating system) and direct contact of dissimilar metals (copper or steel with aluminum) is avoided, an aluminum radiator is guaranteed to last up to 25 years.
An operating pressure of 6 - 16 bar allows you to connect the battery to central heating, but annual testing of the central system with a load of 10 bar requires careful study of the declared parameters.
Injection-molded radiators can withstand greater loads than pressed extruded elements.
Bimetallic models
Bimetallic batteries have a complex structure made of steel or copper and aluminum. To avoid internal corrosion, the steel, which gives the structure strength, is coated with a thin polymer layer. Aluminum, which has high thermal conductivity, is used to cast the outer surface of the evaporator (wide radiator fins). Thanks to the thin-walled rolled steel inside the device and large aluminum sections, the weight of the radiator remains insignificant, while the steel component allows it to withstand pressures of up to 25 bar.
To prevent direct contact of the galvanizing metals, there is an insulating layer of paronite between them. Therefore, the service life of a bimetallic device is longer than that of any other heating element.
High efficiency and the possibility of quick installation make it possible to effectively use a bimetallic radiator for heating very large areas(exhibition halls, trade pavilions). Portable bimetallic oil instruments, thanks to high density thermal carrier, will provide a local thermal curtain in any enclosed space.
Cast iron heating devices
Radiators made of cast iron sections are not subject to corrosion. The properties of the cast iron alloy provide good heat transfer, and the ability to manufacture decoratively designed sections indicates competitiveness.
Among the disadvantages of cast iron heating radiators is their significant weight and the fragility inherent in thin cast iron. The average weight for one section is 5 kg. But appliances made of cast iron hold high pressure, can be equipped with additional sections, and are completely undemanding to the quality of the coolant, and working temperature water can reach 130°C. Heating appliances made of cast iron have a significant service life (about 40 years). Even if the sections are covered with mineral deposits from the inside (due to long-term operation in systems with “hard” water), this will not affect the thermal conductivity of cast iron and general indicators heat transfer.
The variety of types of sections of modern cast iron radiators (1-, 2- and 3-channel, classic and embossed, standard and enlarged) allows you to choose the option that is necessary in each specific case, taking into account all significant factors.
The panel design of a steel battery has a number of its own advantages, the main of which can be considered increased heat transfer. After all, in the radiator body there are channels for coolant, the useful volume of which is larger than that of cast iron analogues. At the same time, the steel heats up faster. Consequently, at the same cost, a modern steel radiator heats up more than an outdated cast iron one. This feature makes steel panels in demand in individual construction, especially in conditions of severe resource conservation.
The range of steel panel-type heating devices includes batteries with lower side supply. Built-in heat regulators provide constant temperature control, and the thin-walled (no more than 2 mm) design instantly responds to changes in the position of the thermostat. Even the fastening system is thought out to the maximum - almost invisible brackets will securely fix the radiator on the wall or floor.
The low pressure (9 bar) declared for steel panels does not allow them to be massively connected to the central heating system with its significant overloads.
The tubular design of a steel radiator has no significant disadvantages, other than high cost. The price of the device is determined by the combination of expensive material and its low heat transfer (due to its specific tubular shape).
By virtue of design features a heating device assembled from steel sections brings not only practical benefits by heating the room. The appearance of a classic model of a tubular radiator can decorate a room; simulated shaped structures can become a starting point in developing a design concept.
Steel is susceptible to corrosion, and anti-corrosion treatment of the finished product will only increase its cost - that’s why radiators are no longer produced from ordinary steel. It is technologically possible to assemble a tubular structure from galvanized steel. The individual segments are connected by spot welding in the manifold area. Moreover, the finished product is completely symmetrical, which allows installation without preliminary pipe routing. This radiator does not corrode and can withstand a system pressure of 12 bar, so it can be purchased for installation in multi-story buildings.
Heating devices of convector type
The operating principle of convectors is based on the natural property of cold air to sink down and hot air to rise upward. A copper tube through which coolant passes is used as a stimulator of this circulation. For efficient heat transfer, the tube is equipped with aluminum plates. They are the ones who heat the sunken cold air, forming a heat flow. The entire process takes place inside a metal box, maximally open at the bottom and partially open at the top. Moreover, the box itself does not heat up. Sometimes supply fans are used to increase air supply.
Such elements of the heating system, which allow you to quickly heat the room, can be made in the form of a separate wall block, bench, or baseboard. In-floor convectors are produced.
This is the only thing the right decision when installing a heating system in a room with low window sills or full-wall windows, because the convector installed near the window rises warm air, blocking the way to the cold coming from the window
Classic models are designed for a pressure of 10 bar, so they can be connected to a centralized system.
Brass, copper and steel are used as materials for the production of water heated towel rails. Models made of brass are designed to work with coolant of neutral acidity, copper and steel are able to operate uninterruptedly in any system. High pressure testing pressure (16 bar) allows you to install heated towel rails both in the heating circuit and in the hot water supply system. In any case, at a pressure of 6 to 10 bar, the device functions trouble-free.
The disadvantage of a water appliance is that seasonal interruptions in hot water supply lead to forced downtime in the operation of the heated towel rail. Otherwise, thanks to the wide range, even a demanding consumer will be able to make a choice.
Electric heated towel rails, while performing the same functions as water ones, are not as economical. But the opportunity to not depend on water supply forces citizens to purchase an electrical appliance.
Combined models imply the presence of electric heating elements in the water heated towel rail. The low popularity of water-electric appliances is due to the fact that if there is no water in the system, they are prohibited from being used.
Radiator as a design element
The most common design radiators can be considered modern water heated towel rails. The variety of models encourages experimentation in bathroom design. However, both in the living room and in the hallway you can install a heating device, skillfully disguised as a mirror, or made in the form of an abstract bas-relief. Lately, backlit models have become popular. Moreover, only the owner of the house knows that this is a functioning radiator.
Design room radiators are not cheap devices, so safe operation is thought about directly at the factory. Moreover, the product is one-piece and is manufactured after a thorough analysis of the heating system and operating conditions.
It is impossible to find negative aspects in devices that ideally combine practical functionality and aesthetics. appearance. The only thing worth remembering when independently purchasing a ready-made heating device abroad is the possible discrepancy between a beautiful radiator designed for a two-pipe system and our single-pipe system. After all, if the suspicions are confirmed, then the miracle of design will gather dust in the closet.
What you need to pay attention to when choosing a radiator
The selection of the required radiator must be carried out, first of all, from a practical point of view. That is, technical characteristics:
Power - at the rate of 1 kW per 10 sq. m.
Working pressure – for central systems from 10 bar, for closed systems – from 6 bar.
Dimensions - so as not to subsequently redo the opening.
It is worth remembering that the acidic characteristics of the coolant (water) are one of the most significant factors when selecting heating system elements. For example, a water acidity index of 8 or higher is not suitable for aluminum radiators.
Once the basic parameters have been determined, you can choose from suitable options models that correspond to your own aesthetic ideas.
Do not forget about possible breakdowns (even if the seller claims a half-century warranty period) and the real possibility of repair (upgrade). After all, having a three-section cast iron radiator in a 20-meter room, theoretically, you can count on connecting additional sections, which cannot be said about an incorrectly selected bimetallic device, which, in a similar case, will have to be completely replaced.
How to choose the optimal radiators
Russia is in such climatic zone, Where heating systems 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 great amount 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 conditions for accommodation 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 maximum temperature surfaces. 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. IN Lately great attention paid attention 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 the domestic 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
Most shining example convective heating method - 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 different quantities sections, which determines the power of the heating device. Sectional radiators can be made of 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. Hydraulic resistance cast iron has a minimum, 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 are 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 that prevent the development of corrosion 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 differ from sectional ones in design. They are made in the form of vertical curved tubes connected to each other at the bottom and top using manifolds. Heat transfer efficiency is affected by various factors- dimensions 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, at Russian manufacturers it is equal to 2mm. The device is designed for a pressure of 10–12 atmospheres, but domestic manufacturers produce models that can withstand a working pressure 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 clean the device, so the tubular steel radiator is the most hygienic model of all existing ones. She 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, in the summer, utility workers drain water from 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 thicknesses. 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.
You can connect heated towel rails to central heating by installing them in a heating cycle. In our country, this element is connected to DHW 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 along 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, the coolant circulates between steel sheets having vertical channels, which increases the usable area of the installation.
IN 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.
- There are products on sale that have different sizes and differ 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 attributed to positive aspects. 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 pure 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 high temperature coolant. 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 aspects. Experts have achieved good success 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 an original design that 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 - here today they use wall-mounted 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. In infrared heaters, heating elements heat up to 800 degrees, while in long-wave heaters - only 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, complex and labor-intensive finishing work will have to be included in the final price. 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 brought detailed classification existing heating devices, identified 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 can provide consumers huge assortment products, giving the opportunity to select installations 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.
