Which heating radiators are better to choose – aluminum or bimetallic

Selecting an appropriate heating system for your house is essential for both energy efficiency and comfort. Choosing the kind of radiators to install is one of the most important choices you’ll have to make. We’ll examine the arguments for and against aluminum versus bimetallic radiators in this post so you can make an informed choice.

Aluminum radiators are becoming more and more popular because of their quick heat transfer and lightweight design. You can heat your living area more quickly with these radiators because of their quick heat-up times. Aluminum also resists corrosion, which contributes to the radiators’ longevity and durability. On the other hand, there have been some worries expressed regarding the possibility that aluminum could react with specific types of water, causing corrosion and leaks.

Conversely, bimetallic radiators, which have an aluminum core with steel or cast iron covers, offer the best of both worlds. The objective of this design is to optimize aluminum’s heat transfer efficiency while reducing the possibility of corrosion by means of an outer layer made of cast iron or steel. Because of their robustness and corrosion resistance, bimetallic radiators are ideal for a variety of heating systems.

It’s important to take your budget, your home’s heating needs, and other factors into account when choosing between bimetallic and aluminum radiators. Although aluminum radiators might have better heat transfer properties, bimetallic radiators have more durability and resistance to corrosion, which can be useful in some situations.

The decision you make between bimetallic and aluminum radiators will ultimately come down to your tastes and priorities. You can choose the heating system that best suits your requirements and guarantees the highest level of comfort and efficiency in your house by weighing the benefits and drawbacks of each option.

On the design of heating devices

Knowing how contemporary batteries work will make it easier to answer the debate about aluminum versus bimetallic radiators. It should be made clear right away that aluminum in this context refers to the alloy called Silumin, which contains silicon. This metal is not used in its pure form. Less than 1% of the alloy’s composition consists of impurities, such as iron, copper, manganese, and zinc, while silicon makes up 14% of its composition. Bimetall is a combination of two distinct metals, in this example, silicon and steel. First things first, though.

Sections made of silumin through casting or extrusion make up the aluminum heating device. A complex shape is made up of these components in each section:

• silumin case (radiator body);
• two longitudinal channels with a diameter of 25 mm with the right and left thread at the edges for twisting sections;
• vertical channel of the round or oval section in size 25-45 mm, connecting horizontal;
• Vertical convection ribs on the sides and in front of the case for better heat exchange with air.

Note: Steel nipples with an inch-diameter cylindrical thread are used to twist sections together. When comparing the batteries later on, the usage of steel fastener details will be useful.

Bimetallic heating devices also consist of an aluminum alloy with a steel pipe frame that has been welded inside. The objective is to enhance the product’s constructive strength and dependability while preventing silomin from coming into contact with the coolant.

Partially bimetallic batteries are still available; these batteries are made of steel pipes with only horizontal channels covering them. It makes no sense to discuss or even purchase such a product.

Comparative analysis of radiators

Which is more important to the purchaser of heating batteries? Three items:

1. So that heating devices warm well and serve for a long time.
2. Product price.
3. Their appearance.

A comparison of appearances can be made right away because the majority of modern sectional radiators have a strong white polymer coating applied to them and share nearly identical designs. All that’s left to do is select a heater whose height matches the location of installation.

It is worthwhile to evaluate which radiators are superior, aluminum or bimetallic, based on the remaining two points. Technically speaking, comparison criteria are expressed as follows:

• good heating provides heat transfer of the heating device;
• The duration of operation depends on the size of the working pressure and the ability to withstand the effects of low -quality coolant (corrosion resistance);
• The concept of price belongs to 1 section of the device.

Citation. Bimetallic batteries became necessary because of the high pressure in apartment and private home central heating systems and the poor coolant quality. From this perspective, it is therefore preferable to compare them to aluminum.

Compare the heat transfer

Aluminum’s exceptional 220 W/m*K* thermal conductivity sets it apart from other metals. This indicator ranges from 150 to 180 W/m*K* for radiator silumin. The only material that performs better than them in terms of heat transfer is copper (λ = 380 W/m*K), but batteries are not made of copper. Within bimetallic radiators, a steel intermediate with a significantly lower thermal conductivity of 70 W/m*K is present between the coolant and the aluminum casing.

The heat transfer of the second will be less if we assume that the temperature and speed of water in the silumin and bimetallic instruments are the same. Steel won’t have as much time as Silumin to remove the heat from the coolant. This is a theoretical statement.

The heat transfer indicators listed by manufacturers in the bimetallic and silumin sections are essentially the same in practice. To confirm this, one need only review the table displaying the data for products from Global (Italy) and Rifar (Russia), two well-known manufacturers:

Note: The heat transfer values are based on specific conditions: the coolant and air temperatures in the room should differ by 70 °C (or 90 °C and 20 °C, respectively). This implies that the batteries will actually start to produce heat in roughly 1.5 times less time.

It will be evident from comparing the section sizes of the models that are being shown that they are able to transfer roughly the same amount of heat flow into the room. Thus, the conclusion is that there is no difference between the two types of radiators in terms of how well they warm.

Which batteries are more reliable

The material’s resistance to corrosion and the radiator’s calculated pressure determine how long heating devices in the central heating network will last. In reference to the pressure on the Internet, a lot of horror stories are floating around, all of which boil down to the same thing: sectional batteries made of aluminum cannot be installed in apartments that have central heating because the hydraulic boards and elevated water pressure will tear them apart.

As a matter of fact, all renowned manufacturers of silumin products test for 24 bar and are intended for a working pressure of at least 16 bar. This is true even though, considering the tests and other operating conditions, the pressure in heat supply networks hardly ever reaches 14 bar. The table, for instance, displays the functional attributes of various well-known brands’ products:

Furthermore, we recommend viewing the video featuring our expert Vladimir Sukhorukov testing the breaking strength of a steel radiator in order to debunk the myth surrounding aluminum batteries. Keep in mind that steel devices are only intended to withstand 6 bar of pressure, in contrast to aluminum ones.

Up to 35 bar, global bimetallic models are maintained, and they undergo testing up to 50 bar. The following table displays the features of other brands:

These kinds of pressure indicators don’t exist in any heating network, with the exception of industrial enterprises’ steam systems. Thus, the reasonable query is, "Why add more costly bimetall when aluminum suffices?" Maybe as a result of the coolant’s exposure to corrosion, which we will discuss later.

Visit your heat supply company and request to see the data from the system testing to confirm the logic is sound (crimping is typically done at a pressure of 12 bar). and after that contrast them with the technical specs of different kinds of heating devices.

All post-Soviet countries have poor coolant in their central heat supply systems, which is a result of the maximum wear on subterranean highways. As a result, only cast-iron batteries can be considered "friends" with this type of water; all other batteries face this fate:

1. Silumin remains persistent to corrosion if the hydrogen indicator of the coolant PH does not leave the range 7-8.5 units. A more acidic environment destructively acts on the alloy.
2. Abrasive particles moving along with water through the channels of the heating device are tirelessly bombarded the surface of the aluminum alloy. True, a fistula from such an impact may appear after many years.
3. Steel pipes of bimetallic radiators also corrodes and “overgrow”, although here to disable the product will need for a rather long time.

Prominent producers of silumin batteries typically coat the inner walls of the channels with a three- or six-gone chromium layer for protection. Application technique: passivation, or electrochemical. In the struggle against corrosion, such occurrences essentially balance the advantages of bimetallic and aluminum heating radiators.

Which is cheaper?

The overall price statistics show that bimetall is, on average, 20–25% more expensive than aluminum. Simultaneously, the additional element-pipe in the steel-framed batteries limits the size of the passing cross section of the channels. We were able to confirm that the remaining benefits and drawbacks of sectional alloy radiators are nearly identical.

The table featuring products from the same well-known brands accurately illustrates the price differences:

Note: The prices of various companies’ products are based on the 500 mm size, which is the most popular.

Choosing between aluminum and bimetallic radiators for heating your home can be a crucial decision, impacting both comfort and efficiency. Aluminum radiators are lightweight and heat up quickly, but they may not retain heat as well as bimetallic ones. Bimetallic radiators, on the other hand, offer better heat retention due to their steel core, making them suitable for spaces where a consistent temperature is desired. However, they tend to be heavier and more expensive. Consider factors like budget, heating needs, and desired longevity when making your decision, as both types have their advantages and drawbacks. Ultimately, the choice depends on your specific requirements and preferences for heating and insulation in your home.

Choosing between aluminum and bimetallic heating radiator models can be difficult when choosing for your home. Prior to making a choice, both options should be carefully considered as they each have unique benefits.

Aluminum radiators are renowned for dispersing heat quickly and being lightweight. They are a popular option for contemporary homes looking for energy efficiency because of their rapid warming up time and effective heating. Furthermore, aluminum radiators are frequently less expensive than bimetallic radiators, which makes them a desirable choice for homeowners on a tight budget.

Bimetallic radiators, on the other hand, offer durability and corrosion resistance by combining the advantages of steel and aluminum. Bimetallic radiators are frequently more resilient and able to tolerate higher operating pressures, even though they might weigh a little bit more than aluminum radiators. Because of this, they can be used in commercial settings or high-traffic areas where longevity is crucial.

It’s important to take your budget and unique heating requirements into account when choosing between bimetallic and aluminum radiators. Aluminum radiators can be the best option for you if cost and quick heat distribution are your top priorities. In case longevity and resistance to corrosion are of utmost importance, bimetallic radiators might be a financially worthwhile purchase.

In the end, the question of which heating radiators are better to choose cannot be answered in a generalized way. It’s critical to assess your priorities, seek advice from heating experts if needed, and decide on the solution that best fits the heating needs of your house while staying within your means.