Which heating radiators to choose – aluminum, steel or cast -iron

Selecting the ideal heating radiators for your house is an important choice that can affect energy efficiency and your level of comfort. With so many options available, including cast-iron, steel, and aluminum radiators, it’s critical to comprehend their distinctions in order to make an informed decision.

Aluminum radiators are perfect for contemporary, energy-efficient heating systems because they are lightweight and heat up quickly. They have a reputation for responding quickly to temperature changes, which can lead to less energy being used and fewer heating expenses. Aluminum radiators also resist corrosion, which adds to their longevity and toughness.

Conversely, steel radiators are robust and adaptable. They are a popular choice for modern homes since they frequently have sleek, contemporary designs. Steel radiators heat up uniformly and hold heat well, giving the space a constant, comfortable temperature. They are still a good choice for heating your home, even though they might take a little longer to heat up than aluminum radiators.

For homeowners who prefer a traditional aesthetic, cast-iron radiators are a favorite due to their sturdy construction and timeless appearance. Because of their outstanding heat retention capabilities, these radiators are a great choice for larger or older homes where keeping a constant temperature is crucial. Even though cast-iron radiators may take longer to heat up at first, their soft, cozy glow persists long after the heating system has been turned off.

The heating needs of your home, your taste in style, and your budget should all be taken into account when deciding between cast-iron, steel, and aluminum radiators. You can choose the ideal radiator type for your home’s insulation and heating needs by carefully considering the benefits and drawbacks of each type of radiator.

The comfort and effectiveness of your home can be significantly improved by selecting the correct heating radiators. Aluminum radiators work well with contemporary, energy-efficient systems because they are lightweight and heat up quickly. Steel radiators are reasonably priced, long-lasting, and compatible with both conventional and modern heating systems. Although cast-iron radiators are heavier and take longer to heat up, they hold heat longer, which makes them perfect for older homes or spaces with erratic heating requirements. When choosing the right type of radiator for you, take into account things like your heating preferences, your home’s style, and your budget.

Battery Choice Instructions – a simplified approach

Look through the catalogs of sizable internet retailers before making a purchase or placing an order for new heating radiators. This will display the current battery types and determine the pricing hierarchy. There are four categories into which all water heating convection devices fall:

• aluminum sectional;
• bimetallic – sectional and monolithic;
• cast iron;
• steel – panel and tubular.

A poetic aside. You can read articles and reviews on websites that rate different brands of products. However, the information won’t be very helpful because there are always arguments on forums, phony comments are posted, and ratings are frequently based on the top 10 manufacturers found on the search results pages.

You must first determine how much heat is transferred during each room’s heating before choosing the radiator power. The calculation techniques—by building area, volume, or thermal losses—are detailed in a different article. How to select the appropriate batteries:

1. Estimate the cost of a future purchase, make more expensive and too cheap heating options.
2. Take the models you like in appearance, shape and color, successfully fit into the home interior. Pay attention to the height of the batteries so that they are placed in the niches.
3. If you live in the apartment of a high -rise building (9 floors or more), open a page with the technical characteristics of the selected radiators and find out the maximum working pressure of the water – the device must withstand at least 12 bar.
4. For the owners of private cottages, the pressure parameter is not of interest – models with any characteristics are suitable. If the house is heated by a wood or coal boiler, it is worth checking the maximum temperature of the coolant – the higher the indicator, the better.
5. Take an interest in what methods of connection are provided for by the manufacturers of selected batteries. The lower eyeliner allows you to better hide the heating highways, with a lateral version of the pipe you will have to ant the wall or leave it in sight.
6. Find out the weight of the product and the installation method – floor or wall. Find out whether the radiator is equipped with installation brackets and footballs, otherwise additional costs will arise. Radiator valves and crane of Maevsky is usually acquired separately.
7. Make the final choice of the model and determine the size of the radiators by power. How the real heat transfer of 1 section (panels) is calculated, we will tell at the end of this instruction.

Be aware that we did not address the types of devices or the materials used in their manufacture. Actually, this is not a major factor. Technically speaking, modern radiators are very similar; the heat transfer indicator is still crucial. The lower working pressure threshold is only significant in multi-story buildings.

Next, we’ll look at the gadget and different battery types, contrasting their benefits and drawbacks. We will, however, first debunk the widespread misconceptions created by marketers.

Heating radiator myths

Three popular myths concerning heating devices made of different materials were created in order to advertise a specific product:

• the heat transfer of aluminum radiators is much higher than steel and cast -iron;
• Cast iron radiators are massive, so they are warming up and cooling for a long time, supposedly stored warmth;
• In the central heating network there are hydraulic boards and pressure, which is maintained only by bimetallic heaters.

Please take note that while we describe radiators, we will address other common misconceptions in addition to the ones that are listed here.

Aluminum conducts heat far better than ferrous metals like steel and cast iron. Let us validate this numerically: 209 W/(m • °C) is the thermal conductivity of λ aluminum products, 47 W/(m • °C) for steel, and only 42 W/(m • °C) for cast iron. The catch is that heating devices are actually made of an alloy called Silumin, which belongs to the AK12 group and contains 11–13% silicon as well as other impurities listed in the table above.

The silicon addition is meant to fortify and improve the alloy’s ability to withstand corrosion. Silumin has distinct physical characteristics; for example, its thermal conductivity is noticeably lower at 168 W/(m • °C). In actual use, there is no discernible difference in the heat transfer of aluminum and iron devices due to the batteries’ 4-5 mm thick walls. You won’t be able to tell which of these two radiators, with the same power, operates more effectively in the space.

Copper is the best heat conductor. It is used in copper-aluminum water convectors and plastic skirting heaters.

One obstacle is the cost of copper-related goods. The heater "Term" worth 70 inches is shown in the right photo. Its measurements are 400 x 400 x 90 mm, and its heat output is only 430 watts.

The transfer of thermal energy from any metal battery is significantly impacted by the following factors:

• the temperature and consumption of the coolant;
• surface area;
• The temperature difference between the air of the room and the water in the pipes.

Citation. Temperature pressure (DT) is the difference between the room’s heated air and the coolant’s average temperature. When figuring out the devices’ power later on, the value is helpful.

On the following points, we will debunk any remaining myths:

1. When heated / cool, the massiveness of cast iron does not play a role, since its heat capacity is 9 times lower than located inside the water (0.54 kJ/kg • ° С versus 4.18 kJ/kg • ° C). Therefore, the cast -iron battery will cool simultaneously with the coolant, no longer longer. Silumin and steel are cooled faster, since they contain a much smaller volume of water.
2. Hydraulic strokes inside centralized heat supply networks simply do not exist. The maximum pressure in the operating mode is 10 bar, the test – 12 bar. Modern aluminum devices calmly withstand such a pressure.

Design and advantages of aluminum appliances

These types of radiators are cast or extruded. The final product is either an integral non-vegetable battery or a vertical single section battery; the renowned Rifar company produces both types). A heater with the necessary power is typed from individual sections, and a threaded nipple with a gasket serves as the connection method.

Two horizontal collectors were constructed inside the silumin radiator section depicted in the picture, and the vertical connecting channel of the oval section was placed between them. Convection ribs, an external heat exchange component, are painted with a powder that is heat-resistant. The manufacturer is identified by the number of plates and the shape of the nuts.

Citation. The height of the battery is used to calculate the separation between the horizontal collector centers. There are three standard performances for aluminum products: 35, 50, and 80 cm. According to the Italian brand Global, the maximum pressure allowed in radiators is 14–16 bar, and the heat transfer of the section with an interface distance of 500 mm is approximately 190 watts.

Benefits of batteries made of aluminum alloy:

• small weight;
• attractive appearance;
• Effective heat transfer is facilitated by a large surface area;
• Small capacity by water – 0.2 … 1 liter depending on the size;
• relatively low price 7 … 10 in. e. for the section, Chinese models – from 5 at. e.

Aluminum has a poor corrosion stability, but in reality, heaters are used in apartments with central heating that lasts for twenty years. The assertion can be traced back to residential settings where excessively harsh water containing calcium and magnesium salts is utilized as a cooling agent.

The second drawback of sectional batteries is that leaks happen at the joints when the non-freezing coolant is filled. Complete modifications don’t have these issues, like the Rifar Monolith.

Bimetal"s pros and cons

As implied by the name, heating devices are composed of steel and silicon. The batteries are identical to aluminum sections on the outside, but inside collectors and vertical channels are filled with iron tubes that have been cooked among themselves. Two issues are addressed by the steel frame design:

• protection of the silumin part from the chemical effects of the coolant in old centralized systems;
• increasing the reliability of the radiator by increasing the threshold of the working pressure to 20 … 30 atm.

As a point of reference. To enhance heat exchange and the water duct, bimetallic models with double vertical channels are available. A row of non-vegetable Rifar Supremo batteries is one example, as seen in the picture below.

Other than these technical differences, the bimetall and aluminum are nearly identical in terms of weight, spaciousness, and power of one section. Radiators’ operational benefits are also maintained, but a few drawbacks emerge:

• The price of batteries is 30-50%higher, for example, the original Bimetallic section of the Global Style Plus company with an interdose interval of 500 mm costs about 15. e. (970 rub.);
• Due to different coefficients of thermal expansion of Silumin and steel, a pipe core can burst at welded joints, carry out repairs and close up a leak-it is unrealistic.

Important addition. There are occasionally valled bimetallic radiators for sale that have steel tubes and are manufactured exclusively inside collectors. The section’s vertical channel is still exposed.

Features of cast -iron "accordions"

Most homeowners are familiar with the battery device that is made from gray cast iron using the casting method. The heater is typed from individual sections twisted by nipples through gaskets, just like its aluminum "counterpart" (a long end key is required).

The two categories of cast iron batteries that are currently available on the market are as follows:

1. Soviet products of the MS-140 brand, the Standard Intersseum interval-300 and 500 mm.
2. Designer models cast in the style of modern, retro and so on. The distance between the traffic jams is arbitrary.

Cheap "accordions" from the MS series, primarily used in production rooms, look a lot worse than any radiators. The section 50 cm can transfer 160 watts of heat, operate at up to 9 bar of pressure, and hold 1.45 liters of water. Price: starting at six. e. (420 rubles).

Beautiful designer batteries come in a wide range of sizes, powers, and other specifications among various brands. The features and costs of decorative heaters from Turkish, Russian, and Czech brands are shown in the table below (decoration locking reinforcement not included).

Note: The intersostean distance and heater thickness in millimeters are indicated by the numbers following the product names.

Cast iron "accordions" are incredibly resilient, long-lasting, and unafraid of corrosion. Retroopiators are unquestionably the best-looking heating device out there. We’ll now address the drawbacks:

• The sky -high price of designer sections is noticeable in the table;
• Cast iron is fragile, split from shock loads;
• solid weight of the product;
• The battery contains 2-4 times more coolant than radiators of other types.

The increased spaciousness of cast-iron sections explains their so-called inertia. In the aluminum section, two liters of water cools down considerably faster than 0.2–0.6 liters. Some extremely challenging modifications, like Retro Style Anerli, are made in the floor version and have legs.

The advantages of steel radiators

Two choices are provided by manufacturers for iron batteries:

• panel – flat and profile;
• Vertical tubular (sectional).

Remark: Both types are offered in a vertical design (see the image above). Well-known brands in the post-Soviet era include Arbonia, Purmo, Korado, Kermi, and others.

Steel plates that have been stamped and have a thickness of 1.2 to 1.5 mm are used to weld hearing panels. To connect the carts, backs are installed from the radiator’s bottom or side. There is convective nuting affixed in between the panels. As indicated by the table, the batteries are categorized into types based on the quantity of heating panels and specific nuts.

Panel heaters’ operational indicators (measured in accordance with the German radiator type 22, installation size 100 x 50 cm; "Kermmi" radiator):

• Permissible pressure – up to 10 bar;
• thermal power of 1550 W at a water temperature at a supply of 75 ° C, the return – 65 ° C;
• The volume of the coolant – 5.4 l;
• Mass units – 28 kg, price – 95 U. e. (6300 rub.).

Panel radiators and tubular radiators share many characteristics. With the same working pressure and mass of 25.9 kg, a two-row Arbonia 3050/22 device, similar in size to the "Kermmy" (500 x 1014 mm) option, produces a power of 1481 watts. The product’s price is the only thing that differs: 430 U. e.

We outline the benefits of panel batteries below, taking into account the cost of each option:

• Steel panels are the most budget option among all radiators;
• resistance to chemical corrosion;
• acceptable design and appearance;
• The whole structure allows you to pour antifreeze into the system and not be afraid of leaks;
• The ability to select power without changing sizes – by adding heating panels and ribs (from 1 to type 10 to 3 pcs. on type 33).

Radiators’ low operating pressure threshold (6–10 bar) is a drawback. We won’t dispute this, but we will invite you to view our expert’s video in which a cheap steel panel is forced to rupture at a pressure of more than 20 bar using an assessment pump:

How to find out real heat transfer

It is challenging to locate accurate power indicators for a panel or individual section when selecting heating devices from an online retailer. Declaring maximum heat transfer, which is nearly impossible to achieve when heated by a country cottage or apartment, is more profitable for sellers. The passport states that the water in the supply pipeline should be 90 degrees, but the actual temperature is 70 degrees, and the indoor air temperature is 20 degrees.

Reference: The heating temperature of contemporary home heat generators is restricted to 80–85 degrees.

To do this, we suggest choosing the following sections on heat transfer:

1. Open the official site of the manufacturer you like and download the instructions for the operation of the device. It exactly indicates at what temperature pressure DT the radiator gives a nominal amount of heat. Focus on the mode of 70 /50 ° C.
2. If there is no instruction, take the manufacturer for the truth and multiply the heat transfer by an increase in the coefficient of 1.5-1.8. Having made one and a half reserve, you definitely will not lose.
3. Choose the last radiators of a single -pipe system with a double margin, since they receive the smallest amount of thermal energy.

The calculation of heat transfer by a given temperature pressure is the most accurate method of selection. The corresponding material provides a detailed description of the calculation algorithm.

Conclusions and recommendations

With regard to pricing and technical indicators, we hope the preceding explanation has assisted you in determining which heating batteries are more suitable for an apartment. Lastly, we will offer a few useful suggestions:

1. Use the instructions given at the beginning of this publication. Choose radiators which is more suitable for you in design and budget.
2. The working pressure of the coolant only matters for apartments of high -rise houses, only bimetallic and aluminum batteries will withstand pressure over 10 bar. Any water heating devices are suitable for summer cottages and private cottages.
3. With a limited budget, feel free to buy steel panels – they are not inferior to other heaters or convectors in heat transfer.
4. Under the gravity system you need to take radiators with a large section of internal channels. It is better not to put steel stamped heaters, only tubular.
5. In terms of ratio, price – quality and set of working parameters is the first place is occupied by sectional batteries from light aluminum alloy.
6. Bimetall should be paid when there is no certainty in the parameters of the coolant – the pressure is unknown, hard water is used.
7. Try not to purchase frankly cheap radiators, blinded from unknown material in China. They will warm, but probably not for long.

Final thoughts on cast iron. Although the MS-90 and MS-140 heating radiators are inexpensive, they have an absurd appearance. Exquisitely crafted models are immensely costly, meaning that average homeowners cannot afford them. The outdated "accordions" of the MS series are a thing of the past, and cast iron becomes increasingly rare.

If your budget permits you to install designer heaters, carefully consider the dimensions of each battery. It is preferable to install a vertical steel heating radiator—a stylish cast iron product—beneath the windows in a narrow wall niche. Ideally, two brackets are used to fasten heavy floor versions to the wall.

Aluminum Radiators	Steel Radiators
Lightweight and Quick to Heat	Durable and Resistant to Corrosion
Efficient Heat Transfer	Variety of Styles and Sizes
Modern Appearance	Can be Painted to Match Décor

There are a few things to take into account when selecting heating radiators for your house. Cast-iron, steel, and aluminum radiators all have advantages and disadvantages of their own, so carefully consider your options.

Aluminum radiators are energy-efficient and perfect for modern homes because they are lightweight and heat up quickly. Additionally, they are resistant to corrosion, which reduces the amount of maintenance they need over time. However, older homes with larger rooms that need more heat output might not be a good fit for aluminum radiators.

Steel radiators work well in both traditional and modern homes because they are strong and retain heat well. They can be customized to fit your interior design because they are available in a range of sizes and styles. However, if not properly maintained, steel radiators can rust, so routine maintenance is required to extend their lifespan.

Because of their timeless appearance and superior heat output, cast-iron radiators are a great choice for historically significant buildings or rooms that need to be very warm. They are a dependable option for heating larger spaces because of their long lifespan and ability to tolerate high pressures. However, cast-iron radiators can be more expensive overall because they are heavy and may need to be installed by professionals.

In conclusion, your unique needs and preferences will ultimately determine which heating radiator is best for your house. Steel radiators are robust and adaptable, while aluminum radiators are energy-efficient and require less upkeep. In the meantime, cast-iron radiators provide a strong heat output and classic elegance. When making your choice, take into account elements like the age, size, and style of your home’s interior design. If you would like more specific advice, don’t be afraid to speak with a heating specialist.

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Heating radiators: cast iron, steel, aluminum and bimetallic. How to choose a radiator

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