What is the difference between aluminum heating radiators and bimetallic ones and which radiator to choose?

After the heating season ends, many begin to think about replacing old radiators. A significant percentage of housing in Russia is represented by Soviet-era panel buildings.

Aluminum radiator - appearance

The cast-iron batteries installed inside them, although they can serve for decades, sooner or later become unusable. They become overgrown with microcracks, rust and become unsafe. As soon as you find the first gaps, be sure - it's time to send the cast-iron monsters to a well-deserved rest. To replace them, the market offers two main types of batteries. In order not to get lost in the choice, it is important to learn what is the main difference between aluminum heating radiators and bimetallic ones.

To choose the right radiator model, it is best to contact professional repairmen. However, if this is not possible, you will have to figure it out on your own and consult with sellers of specialized stores.

Some sellers will try to confuse you, because their goal is to sell the product at a higher price. In addition, other negligent sellers may try to sell you aluminum radiators under the guise of bimetallic ones, and you should know how to distinguish them so as not to overpay for non-existent additional features! To avoid falling for their tricks, read this article carefully.

Which radiator to choose

The radiators that will be discussed in this article are represented by the following two varieties:

• aluminum;
• metal.

The first are not made from pure aluminum, but from its alloy with silicon, the so-called silumin. When buying these batteries, it is best to give preference to the names of domestic production. The technology of their manufacture takes into account the unsatisfactory quality of water in Russian heating systems. Various chemical additives are often added to it, which are designed to reduce heat loss during water circulation. Due to this circumstance, alloys with reduced reaction characteristics are used for production.

Aluminum radiators are produced in the following two ways:

1. Cast under pressure

One of the features of finished products produced using this technology is increased resistance to both water hammer and external damage. This happens due to the uniform distribution of the internal stresses of the installation. It also has precise shapes.

2. Blanks are extruded through the die

This method is called "extrusion". After the individual blocks are ready, they are connected to each other using a press. This manufacturing technique is much cheaper than casting, but the performance of finished products is much lower.Abroad, they have long abandoned the production of batteries using extrusion due to its inefficiency.

Production of heating radiators by extrusion

Radiator in the interior

Attention! Whichever of the above options you choose, be sure to pay attention to the following point: adjoining any other metal inside the water pipe, aluminum begins to instantly collapse. The presence of hot water in the pipes makes this process lightning fast. Therefore, it is necessary to connect the battery to the heating system using reinforced polypropylene pipes.

The sections of radiators are interconnected by means of nipples and seals. To determine the gasket material that suits you, it is important to know which liquid acts as a coolant for the installed batteries. She may be:

• Ordinary water. In this case, simple rubber products that are reliable enough for proper operation of the batteries are fine for you;
• Antifreeze based on glycerin, ethylene glycol or propylene glycol. In addition to it, it is best to purchase paronite seals, since rubber is quickly destroyed under the influence of the above chemical compounds.

Connection of radiator sections

One of the sizes of aluminum radiators

Advantages and disadvantages of aluminum batteries

Aluminum radiators are rightfully one of the most popular on the market. They became leaders due to the fact that their operation has a number of undeniable advantages:

• batteries very quickly warm up the air of the premises;
• those models that were injection molded can be completed with additional sections during use;
• increased working pressure: for standard models it is approximately 10 - 15 atm., And for reinforced ones it reaches 25 atm.;
• the ability to set a comfortable heating temperature for you;
• small dimensions of the device allow you to save more free space in the living room;
• installation of batteries does not require much effort due to the low weight of the case;
• an aluminum radiator can be a stylish addition to a modern interior, the main thing is to beat it correctly;
• the cost of such installations is available to everyone.

Variant of the appearance of the aluminum radiator

However, as they say, "the coin has two sides." The presented type of radiators also has disadvantages:

• the serviceability of the aluminum case directly depends on the quality of the coolant. In the event that the pH level of the water becomes higher than 8, corrosion reactions will begin at the joints. Therefore, if you are not sure about the quality of the liquid that will circulate inside the heating system, it is better to abandon this option;
• private leaks at the junction of the body sections. Low-quality products never last long, therefore, in order to avoid such a nuisance, give preference to more expensive products when buying;
• obligatory installation of an air vent. It is needed to filter the hydrogen that accumulates inside aluminum radiators;
• short operating life of the air vent. Unfortunately, the device will serve you no more than 15 years, after which you will have to replace it with a new one.
• requires the participation of a specialist when installing radiators. Mistakes made during self-assembly will lead to a quick failure of the device.All the money saved on a professional repairman will go to buying new batteries, and you still have to pay for the work.

Radiator as part of the interior

Features of bimetallic radiators

The second option that you can be offered in the store is a bimetallic radiator. The prefix "bi" in the word "bimetallic" means "two". Such a name is given to this type of batteries because they are made from two metals: steel and aluminum.

Let's immediately turn to the positive characteristics of this species:

• steel in the composition of the material from which the case is made will perfectly withstand any surges in water pressure. It is also not subject to corrosion. These properties of the metal provide high strength and many years of faithful service of the device;
• steel sheet provides serious protection of the body from external mechanical damage;
• active circulation of the coolant;
• aluminum coating will ensure rapid heating of the air in the living room;
• battery operating pressure can reach 40 atm.;
• the maximum value of the possible coolant temperature is approximately 130 degrees, while for aluminum products it is only 110;
• durable paint finish. This stability is achieved through a two-stage staining mechanism:

1. First of all, the product is placed in a coloring solution and completely covered with paint;
2. Then, another polymer layer based on epoxy resin is sprayed on top of the dried first stain. Radiators processed using this technology not only look very aesthetically pleasing, but also acquire clearer geometric shapes;

• easy installation and transportation, especially if you resort to the help of professionals.The device of bimetallic batteries is no more complicated than that of simple aluminum ones, however, it is also better to entrust their installation to professionals. How correctly the batteries are installed, how long they will last you;
• the ability to build additional sections directly at your home. However, if you admit that you still want to increase their number, when buying, pay attention to the design of the radiator housing. Some of the models on the market have a solid steel core, so they are not divided into sections.

Bimetal radiator section

One of the options for the appearance of a bimetallic radiator

Let's pay attention to the disadvantages of bimetal devices:

• aluminum used in tandem with steel loses its high heat transfer properties. Due to the presence of a steel core inside the battery, you will have to wait a little longer for the air to reach the desired temperature than you are used to;
• increased price. Since the price of steel is higher than silicon, the cost of bimetallic batteries also increases by about 30% compared to aluminum;
• increased operating costs. Since bimetallic devices boast increased hydraulic resistance, the amount of energy spent on water circulation will also increase;
• improper use of radiators can lead to corrosion of its steel parts. This will definitely happen if bimetallic batteries are installed in your dacha, which is not used in winter. As soon as the heating autumn season comes to an end, it will be necessary to carry out the procedure for draining water from the system.It is because of this that corrosion processes will begin: the simultaneous contact of steel with air and water instantly starts them.
• The small bore of the tubing inside the device is prone to clogging quickly. This shortens the life of the device.

Important! The coefficients of thermal expansion for steel and aluminum differ, which is why loud crackles begin to emanate from the battery after a short period of time. This sound does not mean that there is a problem inside the device. Don't worry, your health is safe!

These modern radiators can work properly even in rooms where the level of humidity is high. Their surface is not subject to corrosion. Such resistance to aggressive environmental influences is given to the radiator by sheet steel, which covers the body of the device with a protective layer.

Inside the bimetallic radiators there are water channels of small cross section. Due to their modest size, they are filled as quickly as possible with hot water coming from a centralized water supply system or an autonomous boiler.

Building professionals consider the purchase of bimetallic batteries and their installation during renovations to be one of the best functional improvements to an apartment. The use of these devices over time fully pays for the money spent on them.

How to distinguish a bimetallic heating radiator from aluminum in appearance?

We have already talked about the advantages and disadvantages of each individual model and you have already decided which radiator you should buy.The main thing at the time of purchase is not to confuse the products, because in this case all your time spent on learning the pros and cons will go down the drain and you will entrust your fate to chance.

If you put two different radiators in front of you, you should be able to easily distinguish which one is which. The main difference between an aluminum radiator and a bimetallic one is that it is made exclusively of aluminum, i.e. the incoming and outgoing pipe (branches), which should be connected to the general heating system, should be made of aluminum and by tapping on it you will immediately understand what kind of metal it is!

How to distinguish the type of metal by knocking

If you tap on steel, the sound will be more sonorous and "metallic", but if you tap on aluminum, the sound will be more muffled. You need to hear it once and remember it for the rest of your life, you can describe it in words, but only by personal example you will 100% learn the difference. Find a piece of steel and aluminum at home and knock on them with various means:

• fingers;
• nail;
• hammer;
• plastic stick;
• wooden stick.

Believe me, the difference will be significant!

In the store, you can do the same manipulation, as you already know how this or that metal “sounds”.

Second way

Look carefully at the very structure of the radiator, from the reverse side visually inspect the “integrity of the structure” for bimetallic radiators, you should notice that at the places where the coolant passes, a “non-solid” structure is noticeable. Even outwardly it can be seen that aluminum is poured over the steel inner tube.

Video - how to choose a bimetallic radiator

Comparison of fundamental differences between aluminum and bimetallic radiators

In appearance, both presented radiators are very similar to each other.They are made in the form of rectangles of metal, the shape of their ribs is flat. The number of sections for structures of both varieties ranges from 6 to 12 pieces. Their heat transfer is also almost on a par with each other, amounting to approximately 170-200 watts.

Today it is very popular to beat every household detail of the room, turning it into a fashion accessory. The same applies to bimetallic batteries installed in your home. The outer coating of the products is always painted in neutral white or gray colors. However, standard store options can be improved on their own by covering them with a specialized bright paint. Customize the radiator with the pattern you like and breathe a special atmosphere into the room.

Manufacturer color options

Heating radiator decoration option

Important! Before buying paint, consult with experts. It is important to choose non-toxic and heat-resistant to keep your health safe.

So, let's summarize and name the main difference in the operation of aluminum and bimetal batteries:

• Aluminum batteries are well suited for installation in country cottages and ordinary private houses. It is there that it is necessary to obtain maximum heat transfer from radiators, especially in winter. Under the condition of low pressure and high quality of the coolant, this is an ideal option for heating suburban housing equipped with an autonomous heating system. It makes no sense to install bimetallic sections, as they can quickly fail;
• Bimetallic batteries, on the other hand, were developed just for operation in the conditions of an urban centralized heating network.Aggressive chemicals have long been added to the water circulating through them to reduce heat loss. The steel core of bimetallic installations easily copes with these impurities, and also withstands hydrodynamic shocks and pressure drops in the system. That is why it is better to use this variety for installation in an apartment, office, etc.

Video - the choice between a bimetallic and aluminum radiator

Why are cast iron radiators hopelessly outdated?

It would be unfair to say that cast iron batteries are so bad. They have been serving people for almost a hundred years! They were massively installed in Khrushchev and stalinkas, located everywhere. These batteries are still used in new buildings, and many residents are in no hurry to part with them. But still, new is new. We have prepared for you a list of reasons that will convince you to part with the cast-iron old men:

• The heat output of one section of a battery made of cast iron reaches approximately 100 watts. These figures for sections of aluminum and bimetallic devices similar in surface area are one and a half, or even two times higher;
• Each section of a cast iron plant requires about a liter of water, while the updated devices require only about 4 liters;
• Unlike light aluminum items, the weight of each section of a cast-iron radiator pulls 6 kilograms. It turns out that the total weight of the battery is approximately 30-35 kilograms. And that's without water!
• Due to inertia, the temperature in such batteries cannot be changed in a short time period;
• The outdated appearance of the devices resembles the times of the USSR. Installing them in your apartment, you take away a few points from the thoughtful design of the room;
• Due to the long heating of the batteries, it is inconvenient to use in private houses with an autonomous heating system;
• Imported boilers in country houses are often clogged with fine clay, which water washes out of cast-iron radiators and fails.

Modern cast iron radiators

Important! Do not spare money when buying new batteries. The lower the quality of the device, the less it will serve you. If during the manufacture the production technology was not followed, soon you will again have to purchase other heating installations. The formation of microcracks, metal corrosion, rapid loss of appearance - this is what awaits overly economical buyers. You should also order the installation of selected batteries from professional builders in order to be 100% sure of the quality of the work done.

Remember, it is you who will live in the house that you equip.