It often happens that for some reason the owners are not satisfied with the installed heating system, or simply the apartment needs to be replaced by obsolete Soviet batteries. Removing old equipment is easy, but choosing new equipment is usually difficult. Not every product of an aesthetic appearance is able to withstand the pressure of the city heating system for decades. Therefore, experts advise choosing bimetallic radiators, which are not inferior to cast iron in terms of reliability and are comparable to them in terms of durability.
What is a bimetal radiator?
As can be seen from the name of the heating device, it is made from two metals that differ in properties. The body is made of aluminum, which is characterized by good heat dissipation and low weight. To enhance the heating properties of the outer part of the battery, they give a special shape for the free circulation of air flows.
Inside the radiator is a steel or copper core through which hot water or other liquid circulates. The pipe material is very durable, therefore it is able to withstand coolant pressure up to 100 atmospheres (some models), and heating up to 135 ° C.
Bimetal product combines the strength of steel and the excellent thermal conductivity of aluminum.
Attention! There are semi-bimetallic heating radiators on the market, which are equipped only with vertical reinforcing steel tubes. The rest is made of aluminium. Such batteries have a higher heat transfer compared to bimetal, which is a plus, and are significantly cheaper. However, the installation of such products in a centralized network is not recommended due to low strength and wear resistance.
Advantages of bimetal
The popularity of modern bimetal radiators is not accidental. They are distinguished by a set of unique properties and advantages.
- The thought-over design of the case is created for the maximum heat emission and free air circulation by the principle of convection.
- Radiators are assembled in sections, which makes it easy to increase or shorten them, depending on the needs of homeowners.
- Monolithic structures are distinguished by the highest resistance to water hammer, complete elimination of leaks and a service life of up to 100 years.
- Bimetal batteries have an attractive design, are presented in a variety of colors and are coated with a two-layer coloring composition that is protected from damage and fading.
- The aluminum body heats up quickly and cools down just as quickly, which makes it possible to thin temperature settings using the controller.
- The steel or copper collector of bimetallic radiators is able to constantly withstand a chemically active coolant.
Note! To prevent corrosion, air should be bled regularly to prevent prolonged contact of oxygen with the inside of the instrument.
- The devices demonstrate high resistance to heat and are able to withstand even 130 ° C.
- A well-thought-out connection system makes installation very easy.
Criteria for choosing a bimetallic battery
To choose the right radiator, you should build on several basic criteria:
- Core materials (steel, copper).
- Battery design (monolithic, sectional).
- The value of the interaxal distances.
- Manufacturer.
Sectional or monolithic bimetal?
More common on the market is the sectional version of bimetallic heating radiators. This is justified by the fact that it gives more scope for installation in various conditions. It allows you to easily add or subtract the required number of sections when calculating the heating area and is distinguished by an affordable price.
The monolithic design has improved performance characteristics: it can withstand significantly higher coolant pressure, easily endure even the most powerful water hammer and has a service life of 100 years. Also, possible leakages between the blocks in sectional radiators are excluded. The described qualities are achieved due to the solid steel core, which has no weak points in the form of docking nipples.
The main disadvantage of a monolithic bimetal is its high cost.
center distance
The center distance is the distance between the location of the lower and upper collectors. As a rule, the parameter is indicated in millimeters. Standard sizes are available from 200 to 800 mm. These options are usually enough to match the radiators to the wiring installed in the room.
More often on the market there are products with a distance between the cores of 500 and 350 mm. These dimensions are standard for most modern new buildings. Difficulties arise when finding narrow 200mm batteries that are well suited for a small kitchen or toilet, and wide 800mm products are usually only available on an individual order.
Choose a manufacturer
Since bimetallic radiators are not cheap and are installed for many years and even decades, it is important to purchase a really high-quality product from a trusted and reliable manufacturer. The following companies have proven themselves well:
- global;
- Sira;
- Rifar;
- STOUT;
- royal.
Note! Products of European brands, as a rule, are of high quality assembly and production materials. Nevertheless, it is not always adapted to the peculiarities of domestic heating systems.
Global
Models of radiators of the Italian manufacturer have earned a good reputation in the CIS. The insides of the batteries are made of alloy steel, the outer part is aluminum alloy. They have all the advantages of high-quality bimetal. The disadvantages include a slight drop in heat transfer with a decrease in the degree of coolant.
The maximum operating temperature is 110 °C, pressure is 35 atm. The range is represented by the following models with a center distance of 350 and 500 mm:
- Global STYLE 350/500. Heat transfer of 1 section - 120 and 168 W, respectively.
- Global STYLE PLUS 350/500. Section power - 140/185 W.
- Global STYLE EXTRA 350/500. The heat output of one section is 120/171 W.
Sira
The Italian brand positions its products as premium products. It stood out in the market due to its high quality and pleasant design based on smooth rounded shapes. In addition, the line has models with a rather rare center distance of 200 and 800 mm. The maximum heat carrier temperature is -110 °С, pressure - 30 atm.
The range includes the following modifications:
- Sira Gladiator 200/350/500 (center distance) - 92/140/185 W (section power).
- Sira RS Bimetal 350/500/800 - 145/201/282 W.
- Sira Ali Metal 500 - 187 W.
Rifar
The domestic company occupies high places in the ratings and successfully competes with European brands. Sections of one of the lines of radiators - Monolit - are connected by contact-butt welding, which creates a monolithic structure that can withstand the most extreme operating conditions and temperatures up to 135 ° C.
The line includes the following popular models:
- Rifar Base 500. The heat dissipation of one element is 136/204 W.
- Rifar Forza 350/500 - 136/202 W.
- Rifar Monolit 350/500 -134/194 W.
- Rifar Alp 500 - 191 W.
Radiators STOUT
The domestic STOUT brand deserves special attention, which is not yet so widespread on the market, but has already earned a lot of positive feedback from users. Batteries have the best performance characteristics: maximum operating pressure - 100 atm, temperature - 135 °C.
Radiators of this brand have many advantages:
- Production at the largest and most famous domestic plant "RIFAR".
- Control at every stage of production.
- Crimping with maximum pressure before and after painting.
- Affordable price, which is achieved not at the expense of quality reduction, but thanks to optimized logistics processes and cooperation with trusted suppliers.
- The number of sections is from 4 to 14, so you can install radiators anywhere.
- The correct geometry of each section, which ensures the highest possible level of heat transfer.
- Adapted to work both in central and autonomous heating systems.
- 10 years warranty from the manufacturer, insurance for 1,000,000 euros in Ingosstrakh.
The line includes 2 models:
- STOUT Space 350 with section heat dissipation 130 W;
- STOUT Space 500 with 180 W section heat dissipation.
Royal Thermo
Another Italian brand of radiators, distinguished by a wide range of products and original design. The PianoForte model looks especially interesting. The order of radiators of various flowers is possible. The design of the batteries is made using the patented Power Shift technology: additional ribs are installed in the vertical collector to increase heat transfer.
Compared to other brands, the radiators of this company are designed for a lower operating pressure - 20 bar. The coolant temperature is also not too high - 90 ° C.
Popular Models:
- Royal Thermo BiLiner 350/500 - 117/171 W;
- Royal Thermo Revolution Bimetall 500 - 116/168 W;
- Royal Thermo Vittoria 350/500 - 114/167 W;
- Royal Thermo PianoForte 500 - 185W.
Price comparison
For objectivity, we present models of radiators of comparable power with a center distance of 500 mm.
| Name | Heat transfer of one section, W | Average price of a section, rub. |
| Sira Gladiator 500 | 185 | 680 |
| Rifar Monolit 500 | 194 | 850 |
| STOUT Space 500 | 180 | 630 |
| Royal Thermo Piano Forte 500 | 185 | 1250 |
Radiators with a center distance of 350 mm:
| Name | Heat transfer of one section, W | Average price of a section, rub. |
| STOUT Space 350 | 130 | 620 |
| Rifar Base 350 | 136 | 670 |
| Royal Thermo BiLiner Inox 350 | 117 | 1575 |
| Global STYLE PLUS 350 | 86 | 762 |
How many sections will you need?
To determine the required number of sections for a specific area, you should first look at the technical data sheet of the radiator. This document contains information about the thermal power of each section, expressed in watts, which will be needed to calculate their number. The required amount of heat generated by radiators depends on the characteristics of the heated area. Consider common options.
| Room parameters | Required power for heating 1 sq. m area |
| One window, one wall facing the street, ceiling height - 250-270 cm | 100 W |
| One window, two outer walls, same height | 120 W |
| Two walls to the street and two windows | 130 W |
How is the calculation made?
Calculating the required number of sections is simple.
- To obtain the required heat output of radiators for the room, we multiply the area by the heating power index, determined from the table above. If the apartment has non-standard high ceilings or panoramic windows, then an amendment is applied and the result is additionally multiplied by 1.1.
- From the passport of the bimetallic radiator, the power value for a separate section is taken. Then the result obtained in paragraph 1 is divided by the figure taken from the instructions for the device. Thus, the required number of sections for the room comes out. Non-integer values are rounded up. They do the same with the number of sections, since often the radiator consists of an even number of them.
Calculation example
To speed up the operation of counting sections, use the following formula:
Ks \u003d P × Mk / Ms
- Ks - number of sections;
- P is the area of the heated room;
- Mk - the power required for heating 1 sq. m;
- MS - thermal power of one section.
For high ceilings or large windows, the resulting Kc value is multiplied by a correction factor of 1.1.
For example, it is required to install a bimetallic radiator in a room of 20 squares of standard height with two walls facing the street and one panoramic window. Applying the formula, we calculate: 20 sq. m multiply by the required heating power of 120 W and multiply by 1.1.We divide the result by the power of one section, for example, by 200 watts.
20 × 120 × 1.1 \u003d 2640 W - the total power of the radiator.
2640 / 200 \u003d 13.2 - the number of sections.
Due to the fact that more often the number of sections is even, we round up and get a battery with a length of 14 sections.
Other calculation formulas can be found here.
For your information. Some suppliers agree to mount or remove the required number of sections from the radiator at the request of the customer.
Is it worth buying?
Bimetallic batteries are the best solution for a modern apartment. Their relatively high price is offset by a long service life, savings from simple adjustment, reliability and a guarantee of protection against leakage and rupture during water hammer. If the prices of European brands "bite", you can choose radiators from Russian manufacturers at a more affordable cost, with a guarantee and insurance. A few more tips for choosing - in the video below.
