Show bimetallic radiators as they are marked. Bimetallic heating batteries. What is a bimetallic radiator

Bimetallic heating radiators: features, types, how to choose

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Today, various types of radiators are used for heating the house. The most popular bimetallic batteries that combine the properties of steel and aluminum. In the article we will consider design features, the pros and cons of such batteries, and also answer the question: how to choose bimetallic Radiator?

Bimetallic heating radiators

How do bimetallic radiators work?

As already mentioned, bimetal batteries are based on two materials: steel and aluminum. The internal part of the structure (pipe), through which the coolant flows, is usually made of stainless steel (sometimes copper). This metal is very durable and does not respond to the negative influence of the aggressive environment of the heated coolant.

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The outer side is made of aluminum and is a casing with fins. Aluminum has high thermal conductivity, warms up in the shortest possible time and the air in the room begins to warm up instantly.

Device bimetallic radiators

The inner and outer parts of each section are joined together by casting. This process is carried out under pressure or spot welding. Using steel nipples and heat-resistant gaskets that can withstand a maximum temperature of no more than 200°C, the sections are assembled into a battery.

The fact that in the design bimetallic The radiator contains parts made of steel, due to a number of positive characteristics that this metal has:

• steel can withstand pressure changes;
• steel is highly resistant to electrochemical influences, while internal surfaces made of aluminum quickly rust, and therefore their service life is short.

However, in turn, aluminum is characterized by high thermal inertness. On the one hand, this is an advantage, but on the other, it is a kind of disadvantage. Aluminum surfaces react very quickly to even minimal changes in temperature. Thanks to this property, you can very quickly adjust the temperature parameters of the heated room.

Due to the high heat transfer of aluminum, less coolant is consumed, while the amount of heat released is identical to that coming from cast iron radiators. That is why the dimensions of bimetallic heating radiators are more compact, and the shapes are very attractive in appearance.

Advantages and disadvantages

By purchasing an installation made of bimetal, your heating system will be provided with many positive aspects:

1. First of all, this long term services. Thanks to the high quality of the design, which combines two good materials, such radiators can operate effectively for 30-50 years.
2. Durability and reliability. These qualities are ensured thanks to the steel core, which is able to withstand high operating pressure and hydraulic shocks.
3. Bimetallic heating radiators are suitable for any heating system, even with low-quality coolant.
4. High heat transfer is another important positive quality. Due to the fact that the outer casing is made of aluminum, heat is distributed throughout the room very quickly. Standard models, in which the distance between the axes is 500 mm, have a heat transfer of up to 190 W, which is significantly more than in radiators made of only one metal.
5. Thanks to the built-in, you can control and regulate the heating temperature.
6. Externally, bimetal batteries are very attractive. Various color and design solutions allow everyone to choose a radiator to suit their taste.

As you can see, bimetallic radiators have a large number of advantages, which determine wide demand for such products. However, there are also some disadvantages that cannot be ignored when choosing:

1. Different coefficients of expansion of steel and aluminum. In this regard, after long-term operation, noise and squeaks may occur in the heating circuit, and the strength of the structure will be lower.
2. During the installation of radiators in a central heating system, heat-conducting pipes can quickly become clogged. This is due to the fact that they have a small diameter. Given this feature, it is better to be careful and install a coarse filter.
3. High price of bimetallic radiators.

Types of bimetallic radiators

Radiators made of bimetal come in two types: monolithic and sectional.

Sectional ones are constructed from sections, each of which, inside horizontal pipe sections on both sides, has a multidirectional thread, through which connecting nipples with sealing gaskets are screwed in.

It is this design that is one of the most important shortcomings of bimetal batteries. The downside is that defects very often appear at the joints, for example, from low-quality coolant. As a result, the service life of radiators is reduced.

Also, in areas where sections are connected, leaks may occur under the influence of high temperatures. To avoid such unpleasant moments, another technology for the production of bimetallic heating radiators has been created. Its essence lies in the fact that initially a solid welded manifold is made of steel, then it is placed in a special mold and aluminum is poured on top of it under high pressure. Such radiators are called monolithic.

Both varieties have their advantages and disadvantages. We have already talked about the disadvantages of sectional ones, but their advantage is that if one section is damaged, then it is enough to just replace it. But if a breakdown or leak occurs in monolithic design, then you will have to purchase a new radiator.

Let's carry out comparative analysis monolithic and sectional bimetallic radiators.

The cost of a monolithic radiator is approximately 20% higher than a sectional one.

Selection of bimetallic heating radiators

When choosing bimetallic batteries, you should pay attention to a number of criteria on which the operating efficiency will depend.

Design

As already noted, radiators can be monolithic or sectional. In order to choose the most optimal option for a specific heating system, you need to know what the operating pressure is in the system. If it is exposed to powerful water hammer, then it is better to give preference to monolithic models. In all other cases, it is recommended to purchase sectional ones, since they are much cheaper.

To purchase a more reliable device, you should know that there are two types. The first type is made of a steel frame, the other is equipped only with steel-reinforced channels through which the coolant moves.

Batteries belonging to the first type are characterized by greater strength and reliability. In such designs, the coolant does not come into contact with the aluminum alloy, as a result of which the risk of corrosion is minimal.

The main features characterizing the first type are weight and cost. They are produced by the following companies: Royal Thermo BiLiner, Global Style, Rifar (Monolit model) and the domestic company Santekhprom BM.

Another type is called semi-bimetallic radiators. The main characteristics of such devices: high heat transfer and more low price. The most popular brands of devices Gordi, Sira and Rifar, excluding Monolit model.

Center distance

Most manufactured models of bimetallic radiators are equally functional. However, the distance between the axles varies among models. Standard distances between axles: 35 and 50 cm.

You can find radiators in which the gap is 20 cm; this length is considered the minimum. Batteries with this distance are produced by the following companies: Sira, BiLUX and RIFAR. The maximum distance is 80 cm; such models are available from the manufacturer Sira.

Material of manufacture

It is important that the radiator withstands the effects of an aggressive environment well if the coolant is of insufficient quality and contains a large amount of alkali and acidity. This is mainly typical for batteries in apartment buildings.

1. It is important that the internal channels are made of the same metal, preferably stainless steel.
2. The wall thickness of the inner pipe should be 3-3.5 mm.
3. The quality and elasticity of the gaskets plays a very important role. They are the ones that influence the reliability of the connections, so rubber or silicone is usually used as the manufacturing material for them. To check the quality of the O-ring, just bend it with your fingers. If the gasket is rigid and inelastic, then this indicates its low quality.
4. If the radiator is sectional, then you should pay attention to the nipples. It is important that they are made of high quality steel. The low quality of these parts is evidenced by the softness of the metal. If it is of poor quality, then the hooks for the key will definitely break off and in this case the nipple will need to be sawed using grinder and remove its parts from the openings of the sections.
5. The width of the front part of the radiator fin should be more than 70 cm. If this figure is lower, this will affect the heat transfer of the radiator in negative side. Most optimal ratio The section size in cross section is 80*80 mm. With such indicators, heat transfer will definitely be high.
6. The thickness of the protruding ribs also indicates quality. This figure should be no lower than 1 mm.

Guarantee

The warranty period also speaks about the quality of the product. If the manufacturer gives a service life of only 1-2 years, this means that the likelihood that the radiators will work with high efficiency is small, because The operational period of a quality product is 20-30 years.

Specifications

The technical characteristics of batteries include dimensions. The height of radiators ranges from 20 to 80 cm. To select a radiator the right size, you need to take into account the distance between the base of the window and the floor and subtract 20 cm from this number. The width is directly dependent on the place where the device will be installed.

Another important indicator is the working pressure, which varies between 15-35 atm. For centralized heating systems it is better to choose maximum values, for autonomous ones it is possible and minimal.

One of the most important and significant criteria affecting the efficiency of radiators is power. This indicator is determined based on the power of one section (it is indicated in the data sheet).

Calculation of sections of bimetallic heating radiators

In order to effectively heat 1 m² of area, you need 100 W of thermal energy. To calculate the area of ​​a room, you need to multiply the width by the length.

N= S*100/P N - quantity radiator sections, S—room area, m², P—specific thermal power of one section.

Use the calculation calculator required quantity bimetallic radiator sections.

Installation of heating radiators made of bimetal

Bimetal batteries must be installed in accordance with the instructions specified in the device passport.

In order to connect a radiator with your own hands, you need to take into account a number of factors:

• It is better to choose the middle of the window as a location for the battery;
• installation is carried out exclusively in a horizontal position;
• You need to maintain a distance of 3-5 cm from the wall to the battery. If you place the radiator too close to the wall, the result will be uneven distribution of heat;
• the distance to the window sill should be 8-12 cm, if it is less, it will negatively affect the heat transfer of the batteries;
• the distance from the floor to the battery is 10 cm.

Installation of all system elements is carried out in a plastic radiator package. This packaging must not be removed until the entire installation process has been completed.
The procedure for installing bimetallic heating radiators:

• Initially, you need to mark the proposed area on the wall where the brackets will be attached;
• then the brackets are fixed;
• batteries are installed on them;
• Next, the radiator must be connected to the pipes;
• then a thermostatic valve or faucet is installed;
• An air valve is installed at the top of the battery.

Manufacturers

Currently, on the heating equipment market you can find a large number different models bimetallic radiators produced by both Russian and foreign manufacturers. Let's look at the main characteristics of the most popular models.

Model	Distance between axles, mm	Section size: width*height*depth (mm)	Maximum working pressure, Bar	Thermal power of the section, W
Rifar (Russia)
Rifar Forza 350	350	415*90*80	20	136
Rifar Forza 500	500	570*100*80	20	202
Rifar MONOLIT 350	350	415*100*80	100	136
Rifar MONOLIT 500	500	577*100*80	100	194
Global Radiatori (Italy)
Style 350	350	425*80*80	35	125
Style 500	500	575*80*80	35	168
Style Plus 350	350	425*80*95	35	140
Style Plus 500	500	575*80*95	35	185
Royal Thermo (Italy)
BiLiner Inox 500	500	574*80*87	20	171
BiLiner 500	500	574*80*87	20	171
Tenrad (Germany)
Tenrad 350	350	400*80*77	24	120
Tenrad 500	500	550*80*77	24	161
Gordi (China)
Gordi 350	350	412*80*80	30	460
Gordi 500	500	572*80*80	30	181
Sira Industrie (Italy)
Gladiator 200	200	275*80*80	30	90
Gladiator 350	350	275*80*80	30	140
Gladiator 500	500	423*80*80	30	185
LLC Litiz (Ukraine)
Altermo LRB	500	575*82*80	18	169
Altermo RIO 500	500	570*82*80	18	166
Grandini (Italy)
Grandini 350	350	430*80*82	16	130
Grandini 500	500	580*80*80	16	167

Thus, high-quality bimetallic heating radiators are able to operate effectively for a long period of time.

Master of Architecture, graduated from Samara State University of Architecture and Civil Engineering. 11 years of experience in design and construction.

The unique characteristics of bimetallic batteries make it possible to replace conventional cast-iron radiators, while the heat transfer efficiency and durability of the new radiators is not inferior to traditional ones, and in appearance they are much superior to the old models. Batteries of this type are successfully used for heating country cottage and for installation in multi-storey city buildings. The steel core is able to cope with the powerful pressure characteristic of centralized networks, and is also resistant to water hammer, from which urban heating plants are not immune.

In addition to strength characteristics, bimetallic products show high resistance to aggressive environments, which is important in urban environments when the coolant is subject to excessive alkalization or has a high acid content.

These devices are light in weight, look attractive, have a high level of heat transfer and a long service life. Selecting a radiator of the required size is not difficult, since manufacturers have launched the production of various models.

Advantages and disadvantages of bimetallic radiators

The devices in question have positive properties, which distinguish them from other types of heaters:

• Extended service life. A device made with high quality without any violations technological process, will reliably heat the room for at least 30 years;
• The steel base gives this product increased strength;
• The steel core, especially if it is made of high-carbon steel, is not afraid of coolant containing excess alkali and acids;
• High degree of heat transfer (up to 190 W per section);
• The radiator is equipped as standard with a temperature regulator that allows you to reduce or increase heat transfer;
• Large selection of colors and many design solutions appearance products allow you to choose a radiator for any interior.

Negative qualities include the following:

• Over the years different ratio expansion of the material can lead to internal friction, which is expressed in the appearance of noise;
• The small inlet and outlet diameters of the radiator pipes, if there are foreign substances in the coolant, can cause clogging. To avoid this problem, it is recommended to install a filter on the supply;
• High price.

Technical and operational characteristics

When choosing a radiator, you should pay attention to its technical characteristics, which are reflected in the product data sheet. Typically, the following information about the device is important for the consumer:

• Power. It is measured in W and determines the ability of the device to transfer the amount of heat into the room at normative meaning heating network at 70°C. Using this indicator,
• calculate the required number of sections for a specific object;
• Strength of the material. This characteristic is important when determining the type of heater based on the pressure of the heating network. It is measured in bar and ranges from 15-35 units;
• Limit level of coolant temperature. Any bimetallic radiator can handle temperatures of +90°C;
• Dimensions. It is important to determine the center distance and correlate it with the dimensions of the liner. There are models with this indicator from 200 to 800 mm. The height, width and thickness of the product must comply with the recommended standards for installing a radiator indoors;
• Volume. Characterize the capacity of the radiator in liters, ranging from 0.15 to 0.4 liters;
• Weight. Standard products measuring 580x80x80 mm weigh about 2 kg.

Bimetallic battery design

Radiators of this type are produced using complex technology by combining two types of metals. The basis of the product is a steel frame, inside which the coolant moves. The rigidity of steel allows it to successfully withstand high pressure and also resist corrosion.

On the outside, the frame is clad in an aluminum casing. Aluminum can heat up quickly and transfer heat to the atmosphere. The casing is also equipped with special fins that direct the flow of warm air into the room.

Prefabricated models are fastened together using nipples with the installation of rubber gaskets. Such connections can withstand temperatures up to 200°C and network pressure up to 35 atm. Cast models have no internal connections.

Types of bimetallic batteries

Bimetallic radiators are available in two types:

1. Cast. In this case, the battery case is cast in special molds;
2. Sectional. This option is assembled from separate sections, which are joined together using a threaded connection.

The convenience of sectional models lies in the ability to add new sections as needed. It will not be possible to enlarge a monolithic battery in this way, but due to the wide range of radiator sizes, they can be selected for any task.

The cost of monolithic models is 20-30% higher than sectional ones.

Both types of bimetallic heating radiators are used for heating installations in residential premises and administrative buildings. Which is better for an apartment depends primarily on the design of the heating network. For standard apartments in multi-storey buildings it is better to use cast products, and in country house Sectional ones can handle the load just fine.

How to choose and what to pay attention to

To decide which radiator to choose, it is necessary to take into account the peculiarities of organizing the heating supply of the house and the following characteristics of the heaters themselves:

• the value of the testing pressure, which is determined when testing the product - this indicator should not be less than the peak values ​​of the heating network;
• if there is a high content of alkali or acids in the heating network, you should choose a heater with a stainless steel or copper core;
• the outer aluminum casing must be of sufficient thickness and not bend under mechanical stress, and the thickness of the rib protruding from the base must be 1 mm or more;
• recommended core wall thickness - more than 3 mm;
• in sectional batteries it is advisable to check the connecting gaskets for elasticity;
• the edge of the battery must have a width of at least 7 cm, this size gives maximum heat transfer;
• the minimum warranty period (less than two years) indicates the unreliability of this device, since the average service life of radiators of this type is 20 years.

Monolithic or sectional

Monolithic cast products can withstand significant pressure and hydraulic shocks, so they should be installed in multi-story buildings. Sectional products are not able to withstand such tests due to the weakening of the structure by the threaded connections of individual parts, but such heaters are easy to maintain and, if necessary, expand, which is impossible in the case of cast batteries in a private home.

Bimetallic or semi-bimetallic

In addition to standard radiators made of steel (or copper) and aluminum, semi-bimetallic heaters are produced. In these products, the inner core is made not only of steel - it also contains elements of aluminum. Typically, aluminum is used to install vertical pipes.

Such a replacement of the base material significantly reduces the strength characteristics of the product, and in terms of durability in aggressive heating systems, semi-bimetallic radiators differ little from conventional ones aluminum batteries. Connection points aluminum pipe with a steel pipe very quickly become unusable due to the difference in the expansion coefficient of these metals when heated.

Semi-bimetallic radiators are slightly lighter than the original, so when purchasing, you should pay attention to this point, since unscrupulous manufacturers may not indicate the exact parameters of the product. These heaters are closer in characteristics to aluminum ones, so it is better to install them in a private home.

Axle distance

All types of manufactured bimetallic radiators are divided according to the distance between the inlet and outlet. Most often, the distance between the axles is 350 or 500 mm, but some manufacturers produce batteries with an interaxle distance of 200 and 800 mm.

Material of manufacture

Most bimetallic batteries are manufactured with a steel frame and an aluminum shell. The steel core copes well with excess network pressure, resists corrosion, and the aluminum shell serves as an excellent heat dissipator. Some manufacturers use high-carbon steel grades, which allows them to achieve higher strength characteristics and durability of the product.

Core.

A more expensive, but best option for bimetal radiators includes batteries with a copper core. This is actually an eternal material with high strength. The service life of such products is at least 50 years.

The best bimetallic radiators

IN retail networks There are many models and brands of bimetallic batteries, both domestically produced and foreign analogues. The reliability rating of bimetallic heating radiators for apartments includes several well-known manufacturers.

Reliable manufacturers

The most well-known and reliable manufacturers include the following companies:

• Global Style. An Italian brand that produces radiators under the following labels: Style, Style Extra, Style Plus. In the product line of this manufacturer, models with standard specifications and products with unique strength characteristics.
• Sira. Also a manufacturer from Italy, which focuses on producing premium products.
• Rifar. Domestic brand. The company has launched the production of heaters with various values ​​of center distance from 200 to 500 mm. The quality of the products is confirmed by a 10-year guarantee.
• Tenrad. The manufacturer from Germany produces heaters for private homes equipped with an autonomous heating system, but the product line also includes devices that can withstand the high pressure of a centralized heating network.
• WARMA. Joint Russian-Chinese venture. The technical specifications are developed in Russia, and the assembly finished products carried out in China. Radiators from this company are used for both stand-alone and central systems heating.
• Könner. Russian company, which produces bimetallic batteries at production facilities in China. The products of this company are also universal. Features include increased anti-corrosion resistance of the metal and high strength, which allows it to withstand powerful hydraulic shocks.
• TENRAD. A German company placing orders for production in China. All products undergo quality testing by German engineers.
• Radena. The development of radiator designs and control of finished products is carried out in Italy. Made in China. The center distance used is from 150 to 500 mm. Most models are great for Russian conditions operation in the central network.
• Fondital. Italian manufacturer of predominantly aluminum heaters. Bimetallic products are also present in the product line, and in terms of quality and cost they can be classified in the premium segment.

This review will allow the consumer not to get lost in a variety of brands and choose a quality product.

Model	Distance between axles, mm	Section size (WxHxD), mm	Maximum working pressure, Bar	Thermal power of the section, W
Rifar (Russia)
Rifar Forza 350	350	415*90*80	20	136
Rifar Forza 500	500	570*100*80	20	202
Rifar MONOLIT 350	350	415*100*80	100	136
Rifar MONOLIT 500	500	577*100*80	100	194
Global Radiatori (Italy)
Style 350	350	425*80*80	35	125
Style 500	500	575*80*80	35	168
Style Plus 350	350	425*80*95	35	140
Style Plus 500	500	575*80*95	35	185
Royal Thermo (Italy)
BiLiner Inox 500	500	574*80*87	20	171
BiLiner 500	500	574*80*87	20	171
Tenrad (Germany)
Tenrad 350	350	400*80*77	24	120
Tenrad 500	500	550*80*77	24	161
Gordi (China)
Gordi 350	350	412*80*80	30	460
Gordi 500	500	572*80*80	30	181
Sira Industrie (Italy)
Gladiator 200	200	275*80*80	30	90
Gladiator 350	350	275*80*80	30	140
Gladiator 500	500	423*80*80	30	185
Grandini (Italy)
Grandini 350	350	430*80*82	16	130
Grandini 500	500	580*80*80	16	167

Models, prices and their characteristics

The most popular and high-quality models include the following bimetallic radiators:

• WB350 from WARMA BIMETALL. This product has dimensions: height – 41 cm, depth – 8 cm, center distance – 35 cm. Refers to prefabricated batteries. The number of sections varies from 5 to 6. The power of one section is 140 W. Maximum network pressure up to 25 atm. 10 year warranty. The cost is 450 rubles for one section.
• WB500 from WARMA BIMETALL. Dimensions: height – 56 cm, depth 8 cm, center distance – 50 cm. Number of sections from 6 to 7. Power of one section 180 W. Maximum network pressure up to 40 atm. 10 year warranty. The cost is 600 rubles for one section.
• Könner. Available with center distances of 350 and 500 mm. Both options can withstand a network pressure of 30 atm. Power from 140 to 190 W. The maximum coolant temperature is 110°C. The volume of one section is 0.14 – 0.18 l. Dimensions: height – 413 and 560 mm, depth – 80 mm, width of one section 80 mm. 15 year warranty. The cost for one section is about 500 rubles. The number of sections is from 4 to 12.
• TENRAD BM350. Maximum pressure 24 atm. The power of one section is 120 W. The coolant temperature is no more than 120°C. The volume of one section is 0.15 l. Dimensions: height – 400 mm, center distance – 350 mm, depth 77 mm, width of one section 80 mm. Cost from 600 to 700 rubles per section. Number of sections from 4 to 12. 50 year warranty.
• Radena Bimetall CS 500. Permissible network pressure 25 atm. The power of one section is 120 W. The coolant temperature is no more than 110°C. The volume of one section is 0.13 l. Dimensions: height – 552 mm, center distance – 500 mm, depth 85 mm, width of one section 80 mm. Cost from 650 to 800 rubles per section. Number of sections from 4 to 12. 15 year warranty.

Calculation of the number of required sections

To calculate the required number of radiator sections to effectively heat a room, you will need to determine the area of ​​the room and know the heat transfer power of one section in W. It is believed that to create comfortable living conditions, 0.1 kW (or 100 W) of thermal energy per square meter is sufficient, which means that to obtain the required number of sections, the following calculations must be made:

1. Find the area (P) of the room (for example, 6 x 3 = 18 m2).
2. Based on the technical characteristics of the product, determine the power (M) of one section in W (for example, 170 W).
3. To determine the number of sections (K), you need to multiply the area by 100 W and divide by the power.

The formula for calculating the number of sections looks like this: K=P*100/M

Installation of bimetallic radiators

If necessary, you can install bimetallic heating radiators yourself. Before starting work, you should read the instructions that came with the equipment and correctly calculate the location of the battery.

The radiator must be placed in the middle of the window opening, the distance from the installation surface is from 3 to 5 cm, the distance from the floor and window sill is at least 10 cm. Having marked the installation location, you can begin installation. The sequence of actions is as follows:

1. Brackets are installed.
2. The radiator is hung on the brackets.
3. Connect to the coolant.
4. Install a thermal valve or drain valve.
5. A Mayevsky valve is installed to bleed off excess air.

Upon completion of all work, the protective film is removed from the surface of the radiator.

Video on the topic

Bimetallic radiators appeared on our market not so long ago, but are steadily gaining popularity. They are called so because they consist of two metals - steel pipes and air duct ribs made of silumin aluminum alloy welded onto them. Their price is about 30% higher than aluminum ones. Why then do they buy them? Because they are more durable and better tolerate the coolants that our boiler houses supply to the network.

From what has been said, it is easy to understand where they are most often placed: in high-rise buildings connected to centralized heating. This does not mean that they do not work in individual heating systems. They work very well, but at the same time they have lower heat transfer (a steel frame is not the best heat conductor) and a higher price. There is no point: the coolant is normal (you control its quality yourself), the pressure is far from critical, so there is simply no point in paying more, it is better to supply it.

Types of bimetallic batteries

First of all, it must be said that not all bimetallic heating devices are made of steel and aluminum. Copper is sometimes used instead of steel. But then they are made not in sectional form, but in panel form. And they cost quite a lot, but they have excellent heat dissipation.

There are also models in which the manifold is made of stainless steel. They are suitable for networks with high level pH, as well as for those who like to take all components of the system with a large margin of safety.

In a fully bimetallic radiator, the entire frame is made of steel, in some - stainless steel

The “steel + aluminum” option is the most common, and when they talk about bimetal, they usually mean it. But radiators made of these metals can be of two types: full or partial.

If inside the sections both horizontal and vertical collectors are made of steel, they speak of “full bimetal”, sometimes the name “reinforced bimetallic radiator” is also found. This is also about him. To increase the heat transfer of the section, two vertical tubes can be placed in it. This is usually done in models with great depth.

If only the vertical tube is made of steel, this option is called "partial" or "semi" bimetallic.

Which ones are better

Manifolds made of steel completely eliminate contact of the coolant with aluminum. This is the moment that interferes with the normal operation of aluminum batteries in our high-rise buildings. The second point is pressure drops that can occur during system startup and in emergency situations. In general, in normal conditions this indicator in any network is within 6-9 atm. But they try to install heating devices with multiple reserves: water hammer can be very strong. According to these parameters better battery from full bimetal:

• their operating pressure is approximately 5 atm higher than that of partial (on average 30-40 atm depending on the manufacturer),
• 100% exclusion of contact with coolant.

What is the disadvantage of such radiators? They are expensive. The manufacturing technology is complex: first you need to weld the structure, ensuring the tightness and reliability of the connection, then fuse aluminum onto the frame, giving it a certain shape. It is also necessary to ensure a reliable connection between two different metals, which is not easy. All this affects the price.

Another negative point: the lower thermal power of the section. The difference is approximately 10% compared to partial bimetal, and 15-20% with a similar aluminum section.

Partial bimetal has lower strength characteristics. Its horizontal collectors are made of aluminum, that is, they are destroyed by the coolant. But the practice of using aluminum radiators showed that in most cases it is vertical collectors that are destroyed. So aluminum in horizontal ones does not greatly affect the durability of heating devices. However, the main task and idea - to exclude the contract between aluminum and coolant - have not been completed. In any case, they are more demanding on the quality of the coolant (pH should be in the region of 6-9, and preferably 7-8) and have lower burst pressure (and operating pressure too).

Now about the positives. These batteries are priced between fully bimetallic and aluminum. They have higher heat transfer. Some models can catch up with aluminum. For example, Rifar Base 500 allows you to shoot more than 200 W from one section (at a temperature delta of 70 o C).

This is the only fully bimetallic radiator from Russian manufacturer"Rifar"

So, which bimetallic radiators are better? I will express my own point of view: if we install bimetal, then complete it. It may be expensive, but it is reliable. And the manufacturer must be chosen wisely. It is quite possible to find high-quality full bimetal, which will be only slightly more expensive in price than partial. But I emphasize once again - this is a personal opinion.

In general, you need to approach it from the point of view of operating conditions. You will need to know the following parameters of your heating network:

• Maximum temperature;
• working and maximum pressure;
• hydrogen index of the coolant (the same pH).

Having this data in hand, you can already decide exactly what is better: a bimetallic radiator with a partially steel manifold, or do you need a frame entirely made of steel.

When asking about network parameters, do not ask for an official answer. You will be given “protocol” values, which, to put it mildly, do not always correspond to reality. It is better to find out this from plumbers who know the real picture, and not the official one.

Manufacturers and prices

Looking through the information on official websites, you can notice one pattern. The description of some models clearly states: all the tubes through which the coolant flows are made of steel. There are even drawings and photographs demonstrating this. In others, there is not a word about what metals the collectors are made of. And these are models from the same manufacturer.

So here it is. Those modifications where there is no mention of materials are partial bimetal. It's just that the manufacturers are silent about it. For what reasons, one can only guess.

Now about the prices. Let's give them in dollars (the exchange rate is not stable, so...) and approximately. We all know that people have different appetites, but we have derived the approximate cost. They are taken from online stores; offline they may differ noticeably. More information about how the companies were selected (if indicated): these are the most popular ones in stores or on forums. And about standard sizes: prices are given for models with an interaxial distance of 500 mm.

	Bimetallic radiators		Aluminum radiators	Notes
	Full bimetal	Partial bimeta ll
"Clean" China	7-10$		6-7$	It is possible to determine what material the collectors are made of only visually
Rifar (Russia)		12$-14$	12$	"Rifar" produces sectional only partial bimetal. Only the “Monolith” is complete, but it is not type-set, but welded. And one at a timesections are not for sale
Radena (Italy+China)	12-14$		10-11$
Sira (Italy+China)	16-18$	14-15$	10-11$	Full bimetal only one model Ali Metal
Ferroli	18-19$	16$	10-11$
Global	19$		10-11$	Only fully bimetallic batteries are produced

As you can see, prices for aluminum radiators (at least from these manufacturers) are not much different. There is a difference, of course, but it amounts to tens of rubles per section. But the spread in bimetallic ones is more than respectable.

If you go by the reviews, there are very few negative reviews about Global bimetallic radiators; the modestly priced Radena has none at all. Moreover, these companies produce only with an all-metal manifold. But one has production located in Italy (), and the other in China ().

All the rest have approximately the same picture: negative reviews occur. But, it is difficult to determine whether the problem is due to an installation error or manufacturing defect. And one more nuance: the prices of Russian Rifar from the manufacturer are lower. The table contains intermediary prices.

Technical characteristics of bimetallic heating radiators

This question is no easier than with prices. Manufacturers - dozens, if not hundreds, models and even more. But we can say about the average indicators (for models with an interaxle distance of 500 mm):

• thermal power of one section (at a temperature delta of 70 o C)
  • full bimetal 160-180 W;
  • partial 170-200 W.
• operating pressure:
  • full bimetal 35-40 atm;
  • partial 25-30 atm.
• maximum coolant temperature:
  • full bimetal 110 o C;
  • partial 100 o C.
• volume of water in sections (capacity):
  • full bimetal 0.18 -0.22 l;
  • partial 0.18-0.24 l.

It is worth considering that thermal characteristics some models may differ both up and down. This is due not only to different compositions of materials and technologies, but also to different sizes. For example, the width of the section is standard: 80 mm almost always, and the depth can vary from 70 mm to 95 mm. It is clear that the heat transfer from a deeper one will be greater; moreover, they have a larger number of fins, which further increases the thermal power.

The height of the sections also changes. The center distance is strictly maintained, but the height of the extended ribs can vary. So, with an interaxial distance of 500 mm, the section height is 552 mm and 575 mm.

The pressure will also differ: different thicknesses tubes are used as a frame, metal of different quality, different sections collectors and even different shapes. What remains more or less stable is the temperature. All other characteristics strongly depend on the manufacturer and the parameters of the model.

Calculation of bimetallic radiators

All you need to know to calculate the number of radiators per room is its thermal power. Here are several calculation methods:

• by area;
• by volume;
• on heat losses.

The most accurate is based on heat losses. This parameter is calculated by a heating engineer. In principle, the operating organization should have door-to-door data. You can find out heat losses your premises with them. For owners of private houses, everything is not so simple: you need to order thermal engineering calculations from specialists.

But having this data, everything is considered simple: you divide it by the power of the section of the model you have chosen and get the number of sections that need to be installed to maintain a comfortable temperature.

For example, a room loses 1600 W of heat, the radiator power is 180 W. 1600/180=8.8 pcs, round up, we get 9 pcs.

Volume calculation method

When calculating bimetallic radiators by volume, SNiP standards are used. According to them, to provide heat to one cubic meter of air in panel houses, 41 W of heat is required, in brick houses - 34 W. To determine the number of sections, you will need to calculate the volume of the room (multiply the width, length of the room and the height of the ceilings), and then multiply the found figure by the appropriate norm. Let's get the amount of heat needed to heat this room. Dividing it by the thermal power of the radiator, we get the number of sections.

For example, a room has the following parameters: width 3 m, length 4 m, ceiling height 2.5 m. 180 W radiators will be installed. Let's calculate in order:

• We get the volume of the room: 3*4*2.5=30 m3.
• If the premises are located in brick house, you will need 30 m 3 * 34 W = 1020 W.
• Now we count the number of sections 1020 W / 180 W = 5.66 pcs.
• Round up, we get 6 sections.

How to calculate sections by area

The easiest way is to calculate the number of sections by area. But it gives the biggest error. It is assumed that, on average, 100 W of heat is needed to heat one meter of room area. In this case, neither the region, nor the height of the ceilings, nor the material of the walls, etc. are taken into account.

To understand how big the error is, let’s calculate the number of sections for the same room:

• The area turns out to be 3*4=12 m2.
• One radiator section with a power of 180 W can heat (based on the norm) 1.8 m 2.
• To find the number of sections, divide the area of ​​the room by this indicator: 12 m2 / 1.8 m2 = 6.66 pieces, round up, we get 7 pieces.

There is an error, and a considerable one. This method is only suitable for approximately determining the number of sections for average insulation in central Russia.

Moreover, both calculations are valid only for those cases when the system parameters are as follows: the coolant temperature in the supply is 90 o C, in the “return” 70 o C, in the room there should be 20 o C. Data on the thermal power of bimetallic radiators (and others too) are given precisely for such values ​​(this is established by the standards). With other parameters, the power will be different. In some cases, the manufacturer indicates heat transfer for other common temperatures.

In addition, the last two methods only give more or less correct results. Considering this, you can supply either more radiators than required, or fewer. Both options are not the best. And all because the calculations do not take into account either the area of ​​the windows or the degree of their insulation. The presence and number of external walls is also not taken into account. After all, what large area occupies a wall facing the street, the more heat is required to maintain normal temperature. To take into account all these and other factors, you need to use correction factors.

Results

Bimetallic radiators are good when low-quality coolant circulates in the network, and strong water hammer is possible. In this case, the steel frame guarantees the integrity of the heating device. Use in individual heating is only advisable if antifreeze is used. There is simply no point in paying more when using water.

A bimetallic heating device is a heating device whose design uses two metals simultaneously: steel and aluminum. At the same time, a bimetallic radiator combines all the advantages of both metals: it has the high heat transfer of aluminum, as well as the strength, reliability and corrosion resistance characteristic of heating devices made of steel.

How does a bimetallic heating radiator work?

Externally, it is not even easy to distinguish a bimetallic radiator from a conventional aluminum heating device. to an experienced master, who installed many heating devices. At first glance, they look absolutely the same: however, a bimetallic radiator is a little heavier, but this does not mean that a more massive and heavier radiator is necessarily made of two metals.

The main difference lies under the outer shell, or more precisely under the outer plates of the heating device, made of aluminum and attached to a radiator core made of steel pipes. Thanks to this design, the coolant moves only through steel pipes and does not come into contact with aluminum. Wherein outer shell The heating device, made of aluminum, quickly heats up upon contact with hot steel and effectively transfers heat to the surrounding space. The predominant one (as with aluminum radiators) is convective heat transfer.

The result of this design is the unique performance characteristics of bimetallic heating radiators, namely:

Ability to withstand operating pressure in the heating system up to 20 atm and pressure testing up to 60 atm

Ability to operate at coolant temperatures up to 130 C.

Of course, in a conventional autonomous heating system, such parameters are hardly achievable, and there is simply no need for them, but such performance characteristics can safely be called a “real godsend” for those who decide to install real steam heating in their home. Bimetallic radiators are also useful for those who want to be absolutely confident in the reliability and durability of their heating system and are afraid of leaks.

In heating systems with bimetallic radiators, you can forget about possible emergency situations and the associated risk of flooding neighbors on the lower floors.

How to choose a bimetallic heating radiator?

When choosing bimetallic heating radiators, you need to know that not all heating devices whose labels indicate two metals used in their construction are equally good and reliable.

The fact is that today there are 2 types of bimetallic radiators on the heating equipment market:

Devices whose core is made entirely of steel. They can be conventionally called “100% bimetallic” or completely bimetallic

Devices reinforced with steel, which can be safely called “semi-bimetallic”, in them aluminum is in contact with the coolant, and, therefore, there is simply no point in talking about any kind of corrosion resistance, reliability and strength.

It should be noted that semi-bimetallic radiators are often passed off as full-bimetallic, selling them at almost the same price. By purchasing such a heating device, the consumer is purchasing a low-quality product whose service life is unlikely to be long.

How to avoid being scammed?

Semi-bimetallic radiators are heating devices in which steel is used only to strengthen the structure. Typically, vertical channels are made from it, connecting the upper and lower collectors. In this case, the radiator housing and horizontal channels for the movement of coolant are made of aluminum. A reliable connection of these two metals is impossible: the vertical channel is simply installed in the radiator housing and is not fixed in anything.

It is clear that during installation or simply due to careless handling, the vertical channel may shift, which will lead to the formation of a leak.

There are often cases when unscrupulous manufacturers make only nipples from steel, calling radiators bimetallic heating devices.

You can recognize deception using a simple magnet. It is enough to bring it to the radiator and, by the level of attraction, determine where in the heating device there is steel and where it is not. You can only buy heating batteries in which horizontal collectors and channels for the movement of coolant connecting them are made of steel, which is only possible in fully bimetallic radiators.

The choice is made: we take full bimetallic radiators!

In turn, fully bimetallic radiators are monolithic and sectional.

Sectional bimetallic heating radiators consist of separate sections, which are then connected into a single heating device. Each section is made from a steel billet, which consists of two horizontal pipes (cores) connected to each other vertical pipe smaller diameter, filled under pressure with molten aluminum. The result is a strong and reliable structure made of a steel base designed for the movement of coolant, and an outer aluminum casing that effectively transfers heat to the surrounding space.

When connecting sections, various sealing gaskets are used to ensure the tightness of the heating device.

The distance between the cores can vary from 20 cm to 120 cm or more, which makes it possible to produce radiators of various heights and thermal power, suitable for heating almost any room.

If desired, you can assemble a heating device of almost any thermal power from separate sections.

Among the disadvantages of sectional bimetallic radiators is the vulnerability of connecting individual sections to each other, which makes it impossible to use them in heating systems filled with antifreeze, as well as in autonomous systems with steam heating. (a leak may form at the junction of sections)

Sectional bimetallic radiators can work with coolant heated to a temperature of 95 C and operate for a short time when the coolant is heated to 115 C, withstanding pressure in the heating system up to 3.5 MPa.

Monolithic bimetallic radiators

More reliable and durable are monolithic bimetallic radiators, the design of which does not have separate sections. Inside them, steel channels through which the coolant moves are connected by welding in single design, then poured under pressure with an aluminum alloy.

Thanks to this device, there are no separate elements or gaskets in the monolithic radiator, which means there is no room for leaks.

At the same time, the heating device has a high thermal output, has low thermal inertia and can withstand truly extreme loads. In particular, monolithic bimetallic radiators can withstand pressure testing up to 150 atm and heating the coolant up to 135 C.

The height of monolithic bimetallic radiators can also be different, and their thermal power depends on the geometric dimensions of the heating device and is a constant value.

Advantages and disadvantages of bimetallic heating radiators

Bimetallic radiators are characterized by high heat transfer. On average, one section has a power of 170-190 W (more precise characteristics are indicated in the device passport)

Bimetallic radiators can be installed in any heating system (autonomous, central, with plastic or steel pipes)

Heating devices can have any geometric dimensions, which allows them to be matched to any interior design and installed even in limited space

Bimetallic radiators are durable. Monolithic heating devices are designed for a service life of at least 25 years

Bimetallic radiators have low thermal inertia, which allows them to be used in regulated systems heating

The only disadvantage of bimetallic monolithic heating radiators is their relatively high cost, and also the fact that it is not possible to change the power of the radiator or reduce its size.

The efficiency of the batteries determines the speed and quality of heating. The modern equipment market offers all kinds of solutions. One of decent options are bimetallic heating radiators that meet the main requirements of the heating network: strength, resistance to water hammer, high heat transfer and durability.

We will tell you how to choose the right heating device, in the manufacture of which two metals were used. Our article describes in detail the varieties popular among consumers. Their technical characteristics are given and leading manufacturers are listed.

Externally, bimetallic models resemble ordinary ones. The difference lies in the internal content. The design of composite products consists of two basic elements: internal steel pipe and an external figured-ribbed body made of aluminum panels. Some radiators use copper instead of steel.

The coolant circulates through an internal steel or copper pipeline. Due to corrosion inertness, radiators do not rust and do not react with chemically active coolant. External elements And internal manifold connected by spot welding or injection molding.

Based on their physical and operational properties, the batteries are suitable for installation in apartment buildings of any number of floors and for arranging a local heating system for cottage buildings.

The bimetallic structure determines the characteristics of the device. The steel core explains the resistance to aggressive environment and resistance to pressure changes, the aluminum “shell” increases heat transfer and makes the radiator lighter

Features of different heating convectors

You should understand the differences between different types of batteries made of two metals. Composite products are usually classified according to the following criteria: composition of the internal rod, external design and type of metal used.

Bimetallic and semi-bimetallic radiators

Users often confuse true bimetallic batteries with “half-breeds” - semi-bimetallic counterparts.

"Pure" bimetal

Aluminum is used to make the outer casing of the device. The convector core is 100% stainless steel or copper. During the production process, pipes placed in special molds are filled under pressure with aluminum - a sealed structure is formed.

The outer shell is not in contact with the coolant and acts as a heat exchanger. main feature bimetallic radiators - high strength and guarantee against leaks

A high-quality bimetal withstands the pressure of centralized and autonomous system heating.

The internal “skeleton” of the radiator is assembled from two metals: vertical guides - stainless steel, horizontal pipeline - aluminum. The reverse combination is also possible.

Such an alliance of metals is not able to ensure adequate reliability of central heating communications. The coolant may contain alkali, which, when interacting with aluminum, provokes corrosion. Over time, destructive processes “transition” to the steel components of the radiator.

In addition, the integrity of the product may be at risk due to thermal expansion of metals - leaks are possible at boundary temperatures.

Externally, semi-bimetallic radiators do not differ from their full-fledged bimetallic counterparts. "Half-breed" gives lighter weight and lower cost

It is better to avoid purchasing a low-quality composite, especially if we're talking about about centralized heating.

Sectional and monolithic models

Among the variety of bimetallic heating batteries, there are two types of designs:

• sectional:
• monolithic.

Models assembled from sections are attractive due to their variability of characteristics. They provide the opportunity to purchase the device with exact values heat transfer required for heating rooms. Monolithic ones do not have such advantages.

Typesetting systems

Collapsible radiators, the panels of which are connected using nipples. Horizontal sections of pipes of individual sections have multi-directional threads for joining the fastening nipples and the sealing strip.

Stacked models are more popular due to their practicality - it is possible to regulate the thermal power by adding or subtracting the required number of sections. An additional advantage is maintainability.

Disadvantages of sectional radiators:

• joints are weak points of collectors where leaks are likely;
• limited operating pressure – up to 20-30 bar.

Significant disadvantages also include partial ingress of coolant onto the aluminum “jacket” during leakage.

Monolithic devices

One-piece modifications do not have the listed disadvantages. The cast radiator is capable of withstanding pressure surges within 100 atmospheres.

Disadvantages of monolithic batteries: there is no possibility to vary the thermal power, inflated cost - 20-30% more expensive than sectional models with similar parameters

For high-rise buildings (10 or more floors), experts recommend choosing solid radiators, since there will be significant pressure in the heating system.

Copper or steel core?

Most manufacturers offer hybrid batteries with a steel tube frame. The main reason is the affordability of the metal and good strength characteristics. The symbiosis of steel and aluminum made it possible to achieve resistance to vibrations, increase the level of heat transfer of the convector and reduce its inertia.

In copper + aluminum radiators, the heat exchange tubes are made of copper. Heating panels - aluminum plates soldered to an internal copper frame

Advantages of copper core batteries:

• there is no likelihood of corrosion;
• a copper pipeline withstands any water hammer - the best option for use in domestic centralized heating systems;
• high efficiency of the device - the heat transfer of copper exceeds that of steel.

Copper-aluminum radiators have a service life of more than 50 years. The disadvantage of copper modifications is the high price.

Technical and operational characteristics

All basic parameters of the radiator are indicated in the passport of the heating device.

In order not to make a mistake with your choice, you need to understand the meaning of the following characteristics:

• heat transfer;
• operating pressure and temperature;
• center distance;
• dimensions;
• capacity, section weight.

Thermal power. The parameter indicates the amount of heat transferred from the battery to the atmosphere of the room at a given temperature (+70°C). The indicator is measured in W.

The average heat transfer value of a composite radiator is 140-190 W. The difference in values ​​is explained by the dimensions of the section and the design features of devices from different manufacturers.

Based on the thermal power of one section, the required battery performance for the entire room is calculated.

Work environment indicators. The maximum coolant pressure depends on the thickness of the steel core. The choice of strength is at the discretion of the manufacturer. The parameter value ranges from 15 to 35 bar and is determined based on the operating conditions of the battery.

An important characteristic is the limiting temperature of the coolant. All high-grade bimetals can withstand +90°C. Some manufacturers claim higher thermal resistance.

The maximum temperature stated in the equipment data sheet for different trade positions: Global Style – 110°C, Tenrad – 120°C, Altermo – 130°C, Grandini – 120°C

Radiator dimensions. Dimensional characteristics include the following parameters:

1. Center distance– “distance” between the axes of horizontal collectors. The standard size is 20-80 cm. Vertically oriented models with increased interaxial distance are used if the room layout is not suitable for installing horizontal radiators.
2. Geometric parameters determine the height, width, depth of the section. The total height of the radiator often exceeds the interaxial range by 6-8 cm. The traditional width of the fins of bimetallic models is 80 mm.

The depth of the section is 75-100 mm. Some manufacturers except external panels parallel fins are added to the design to increase heating efficiency due to convection currents.

Overall dimensions: a – section height, b – distance between horizontal axes, c – battery depth, d – width of one section. The most popular products with a core height of 35 cm, 50 cm

Volume and mass. In bimetallic modifications, the coolant circulates through a core of round cross-section, in contrast to aluminum counterparts with a heat conductor of oval cross-section. The capacity of one bimetal section is less than the volume of an aluminum section with the same standard sizes.

For example, in convectors with an interaxial range of 500 mm, the coolant filling is about 0.2-0.38 l, with a core height of 350 mm - 0.15-0.25 l.

The weight of a standard bimetallic battery with dimensions of 580/80/80 mm (height/width/depth, respectively) and an axial distance of 50 cm is 1.8-2 kg. Less mass is one of the signs of a semi-bimetal.

Comparative analysis: bimetal and competitors

Before choosing a bimetallic or other radiator, it is advisable to compare its capabilities with its closest competitors. For composite convectors these are aluminum, cast iron,...

The assessment should be carried out according to the main criteria:

• heat transfer;
• endurance to pressure changes;
• wear resistance;
• ease of installation;
• appearance;
• durability;
• price.

Heat release. In terms of heating efficiency, aluminum units are the leaders, bimetal takes an honorable second place. The steel ones are losing noticeably.

Aluminum is characterized by minimal thermal inertia - after starting the system, the air in the room warms up within 10 minutes

Resistance to water hammer. The most durable are bimetallic units, capable of withstanding up to 40 atmospheres (sectional models). The maximum operating pressure on an aluminum heating system is 6 bar, a steel one is 10-12 bar, and a cast iron one is 6-9 bar.

It is the bimetal that can withstand numerous water hammer shocks from a centralized heating system. This property is a key argument in favor of composite radiators for apartment buildings.

Chemical inertness. According to this criterion, positions were distributed as follows:

1. Cast iron. The material is indifferent to adverse environments. Cast iron radiators can be used for decades, transporting an “alkaline”, “acidic” environment.
2. Steel and bimetal. The steel core itself withstands the effects of aggressive components. The weak point of a steel pipeline is its interaction with oxygen, contact with which leads to the formation of rust.
3. Aluminum. The metal reacts with various impurities in water.

Aluminum walls are especially susceptible to acidic environments - the pH of the coolant must be within 8. Otherwise, corrosion will actively develop.

Easy to install. In terms of installation, aluminum and bimetallic products are easier. Cast iron radiators are more difficult to install due to their impressive weight.

In terms of durability, the leaders are composite and cast iron batteries. Aluminum and steel products, subject to operational requirements, must be replaced after 10-15 years. Among the designated batteries, bimetallic ones are the most expensive

We can conclude. The purchase of a bimetallic radiator is definitely justified for assembling a heating network in a multi-storey building, where there are risks of pressure surges and contamination of the coolant. In a private house, with stable operation of the boiler and filtering of incoming water, you can use affordable aluminum batteries.

What should you consider when choosing a radiator?

To achieve the right thermal effect it is necessary to calculate the total battery power. Bimetallic equipment is not a cheap purchase, so you should take care of its durability. The conscientious execution of the radiator is guaranteed by trusted manufacturers.

Capability assessment - thermal calculation

Having decided on the appropriate technical characteristics and dimensions of bimetallic radiators, it is necessary to calculate the required number of sections.

Basic formula: N=Ptot./Ppass., where Ptot. – required battery power for the entire room, Ppass. – thermal power of the section according to accompanying documents

The section’s heat transfer rate is taken from the radiator’s passport, and the total power must be calculated.

Calculation by area

The normalized value of thermal power per 1 sq.m of living space for the average climate zone, subject to standard ceilings (250-270 cm):

• the presence of one window and a wall with access to the street - 100 W;
• there is a window in the room, two walls adjacent to the street - 120 W;
• several windows and “external” walls – 130 W.

Example. Section power – 170 W, total area of ​​the heated room – 15 sq.m. Additional conditions: window – 1, external wall – 1, ceiling height – 270 cm.

N=(15*100)/170 = 8.82.

Rounding is done upward. This means that to heat the room it is necessary to use 9 sections of 170 W each.

Calculation by volume

SNiP separately regulates the amount of thermal power per 1 cubic meter of space in the amount of 41 W. Knowing the volume of the heated room, it is easy to calculate the heat transfer of the entire battery.

Example. Heating the room with the previous parameters. For the purity of the experiment, we leave the power of the section unchanged - 170 W.

N=(15*2.7*41)/170= 9.76.

It is necessary to install a radiator into 10 sections. The second calculation is considered more accurate. When calculating, attention should be paid to sources of heat loss indoors.

The calculated value must be increased by 10% if the apartment is located on the first/last floor, the premises have big windows or wall thickness does not exceed 250 mm

How to avoid fakes: radiator inspection

In addition to analyzing passport data, it would be useful to conduct a visual assessment of the product. Some manufacturers, in pursuit of customers, tend to “embellish” their products by introducing incorrect data into the documentation.

First of all, pay attention to the thickness of the core and the aluminum “shirt”, dimensions, weight and quality of components.

The minimum thickness of the steel tube is 3 mm. With smaller standard sizes, the declared strength of the product - resistance to and development of corrosion processes - is significantly reduced.

Walls thin metal provide access to the coolant to the aluminum “shell”, which, due to chemical activity, begins to quickly collapse

The result of a low-quality steel core is the formation of through holes and the creation emergency situations on the heating network.

Radiator fins. Aluminum panels must be checked for strength - they should not bend from the efforts of the fingers of one hand. The minimum thickness of the panels is 1 mm.

It is better to choose models with profiled channels between the ribs. The formed confuser increases the speed of air flow, increasing the intensity of convective heat transfer.

To reduce the risk of injury, the outer edges of aluminum panels are rounded. There should be no streaks, uneven coloring or “gaps” on the surface.

Dimensions and weight. By individual order It is possible to manufacture radiators with a section width of less than 80 mm. However, store-bought models with inappropriate parameters are most likely fake.

To reduce costs, some manufacturers significantly reduce the width of the internal ribs, “masking” them behind standard-sized front panels. This measure worsens the heat transfer of a bimetallic radiator.

Battery components. It is almost impossible to check the quality of gaskets and nipples on site. Rely on the manufacturer's name and warranty period. Reliable companies guarantee up to 15-20 years of trouble-free operation.

Rating of popular manufacturers

The review includes high-quality foreign heating systems and domestic products adapted to the changing conditions of heating networks.

• Global Style (Italy);
• Sira (Italy);
• Rifar (Russia);
• Tenrad (Germany).

Place #1 – Global

This is a generally recognized leader in the production of heating radiators.

The company produces three series of bimetallic batteries:

• Style – basic characteristics;
• Style Extra – compact dimensions;
• Style Plus – maximum heat transfer.

The sections are connected by paronite gaskets, ensuring the tightness of the joints. Efficient heat transfer between metals is achieved through injection molding of an aluminum “jacket”.

Additional characteristics: pressure – up to 35 atm, connection diameter – ¾ or ½ inch, coolant temperature – up to 110°C, outer shell – double painted

Place #2 – Sira

The Italian manufacturer positions its products as premium products. The devices have gained popularity among consumers due to their durability and attractive design. The manufacturer provides a 20-year guarantee for a series of full-fledged bimetallic radiators Sira Ali Metal.

Characteristics of Ali Metal products: center distance – 350/500 mm, heat transfer of models – 187/141 W (according to the center distance), pressure in the heating network – 35 atmospheres

Place #3 – Rifar

A domestic manufacturer has developed a wide range of bimetallic radiators:

• Base – models with center distances of 200/350/500 mm, warranty from Rifar – 10 years;
• Forza – reinforced external coating, resistant to scratches and mechanical damage;
• Alp – shallow depth (75 mm);
• Monolit is a one-piece radiator.

Monolit series batteries are distinguished by the highest performance indicator at high blood pressure coolant.

Technical data: operating pressure – 10 MPa, destruction pressure – 25 MPa, maximum temperature – 135°C, warranty period – 25 years

Location #4 – Tenrad

German quality bimetal is suitable for centralized and. Suitable for use in gravity, elevator and pump systems with one- and two-pipe wiring.

Distinctive features:

• the thickness of the vertical tubes is 1.8 mm, the thickness of the collector walls is 3.6 mm;
• three-row fins;
• the side panels are located at a slope, which creates a diffuser effect for convective flow.

Double layer enamel coating made of high-quality paints and varnishes – when heated, the device does not emit harmful fumes.

Tenrad products are designed for operation in a system with a coolant pressure of up to 35 atmospheres. Bimetallic radiators are certified and comply with the European standard EN442

You will be introduced to the rules for calculating the power and number of radiators for a heating device, which you should read before purchasing devices.

Conclusions and useful video on the topic

The video review clearly demonstrates the design features of composite radiators and the basic requirements that a high-quality device must meet:

Full bimetallic radiators combine the positive characteristics of both materials. The batteries are characterized by high thermal power, resistance to water hammer and excellent decorative properties. Their purchase is a justified investment provided that you purchase a certified product.

Tell us about how you chose a bimetallic heating device for own apartment or country house. Share what argument was decisive in your choice? Please leave comments in the block below, ask questions, post thematic photographs.