How do cast iron radiators differ from bimetallic radiators
Cast iron radiators were installed in apartments and houses during the Soviet period. Devices had a simple design and were used to connect to the central and autonomous heating systems.
Widespread use was due to the durability of cast iron, as well as its ability to withstand high pressure. Cast iron does not react chemically with the coolant, has little corrosive properties.
The low heat output of cast iron was not paid much attention because gas and other fuels were cheap. The average heat output of one radiator section was 120.130W. A large amount of thermal energy is required to heat the thick-walled metal. To maintain a heating temperature of 45 ° C, you need to heat the coolant to 75 ° C.
The differences between cast iron and bimetallic heating radiators are easy to understand by looking at the design features.
The internal construction of a bimetal consists of:
The core. inside the structure is a steel or copper tube through which the coolant circulates. Only the inside of the battery is in direct contact with hot water. Steel and copper are not susceptible to corrosion and do not deteriorate under the influence of an aggressive medium.
Bimetal heating radiators differ from cast iron radiators by their construction. Aluminium, steel or copper metals with maximum heat transfer efficiency are used in production.
Choose a radiator. Cast iron or bimetallic?
Radiators made of cast iron, are sectional radiators with wide water channels, have a variety of design and shape. Number of sections is determined based on the heat loss of a particular room, between the sections, for tightness, install heat-resistant gaskets of rubber or paronite. At the moment, manufacturers produce sections with different dimensions in height, width and depth.
Cast iron radiator. reliable long-lasting heating device with only a couple of disadvantages: considerable weight and thermal inertness.
On the market there are designer radiators, artistically cast from cast iron. These devices not only heat the room, but also become a decorative object. But the cost of such radiators is incomparable with analogues.
What radiators are better? Cast iron or bimetallic
Practice shows that not every type of radiator can withstand the peculiarities of our centralized heating system. At the moment the most durable are cast-iron and bimetallic devices. Only they are not subject to corrosion and can withstand high pressure. After considering the features of each product and their technical characteristics, let’s try to figure out which radiators are better bimetallic or cast iron.
Design and appearance
Bimetallic products consist of two parts. They are based on a strong steel core. And the casing is made of aluminum. Due to the high thermal conductivity of metal, the heat return to the room is increased.
Most models available consist of sections and have an attractive design.
Semi-metal radiators are also available. In them only the vertical channels are made of steel. Such a device gives a lot of heat, but is not particularly reliable and durable.
Cast-iron radiators today have slightly changed their appearance. They are made both in the classical style, and in a more modern. But still consist of several sections and have large diameter channels. For greater heat transfer, each section of the device consists of 2 parallel channels.
Products made of cast iron have a variety of sizes:
This allows you to choose the right device to suit the size of the room.
The leading speed of heating is a bimetallic radiator. Appliances heat up almost instantly, but unfortunately cool down just as quickly in the absence of heat supply. In this case, the heating of the room is based on the principle of convection heated air rises and its place is filled with cold. This can also be attributed to some disadvantages.
The heat output of one bimetallic section (the amount of heat emitted by the device) is 150-180 W.
Cast-iron heats much more slowly, but also cools down for a long time. This is especially important if there is a sudden heat loss, the batteries will remain warm for quite a long time. Heating of the room with such devices is mainly by the ray method. This means that not only the air is heated, but also objects in the vicinity of the radiators.
The index of thermal capacity of cast iron varies from 100 to 160 W.
How well the devices can withstand the increase in pressure
For multi-storey houses this question is far from idle. There are frequent pressure fluctuations, and sometimes there are water hammer.
Bimetal products are not afraid of the most abrupt changes in pressure. Depending on the model, they can easily withstand pressure of 20-50 atmospheres.
Cast iron radiators can withstand up to 12 atmospheres. For the normal functioning of the heating system is enough. But in the case of water hammer the brittle cast iron can burst.
Радиатор биметал алюминий чугунный стальной панельный Что лучше
The ability to withstand maximum temperature and resistance to the quality of the coolant
The water coming from the pipes into our radiators is neither pure nor chemically neutral. Also the temperature of the heat carrier is unstable.
Bimetallic devices successfully cope with all the difficulties and vicissitudes during the heating season. Bimetal is resistant to chemical additives in water. However, when the water from the system is drained during the warm period, the steel core can be slightly corroded.
With regard to temperature ratings, products can withstand temperatures up to 1300C.
Cast-iron radiators can withstand the temperature of the heat-carrier up to 1100 C, but in general the device tolerates temperature differences well. Cast iron is not affected by the high level of chemicals in the energy carrier. There is also no need to fear that the device will corrode after draining in summer. But the bottom of the radiator gradually accumulates small particles. Over time it causes a decrease in the capacity of the coolant and reduces the heat transfer.
Long service life
Bimetallic products appeared not so long ago. That is why it is not yet possible to estimate their real service life. The manufacturer provides a warranty of 15-20 years.
Cast-iron products with proper care and periodic flushing can serve 50 years or more. It has already been tested in practice. So in terms of durability, cast iron is the best.
What radiator is easier to install
Bimetallic radiators are much easier than cast-iron ones, it is easy enough to install them. If properly installed, they can be installed on any surface, even a plasterboard wall.
Обзор батарей отопления. Сравнение Сталь, Чугун,Биметал,Алюминий!
Problems with the installation of a cast–iron battery will be much more. It requires special brackets, the device can only be mounted on a solid wall. Because of the large weight, there are difficulties with its transfer and installation.
Which radiator is better
Comparing the characteristics of products made of bimetal and cast iron, you can see that each of them has its pros and cons. So make your choice based on what kind of house you live in:
- In high-rise buildings it is better to install bimetallic batteries that can withstand a large load of extreme temperature and pressure.
- In his own house with an individual heating system, where there are no sudden changes in temperature and pressure, you can put cast iron appliances. They will keep you warm even if you forget to put fuel in the boiler on time.
You can watch a video about the advantages of each of the devices and make your choice.
Steel radiators are considered the best option for private homes
the choice is very wide, various parameters and even design models are available for sale. Consider the 7 main advantages:
- inertia-free devices
- the best price per kilowatt of heat
- high heat output
- do not blow out
- easy to clean, unlike the sectional boilers
- Moevsky faucet, plugs and kit for attaching to the wall. come complete with radiator
- radiators with bottom connection are completed with a thermostatic valve
Technical characteristics of steel radiators distinguish them from other models. Against 7 main advantages we can single out only one significant disadvantage: it is better to install the radiator on a prepared (plastered), levelled surface. Another small disadvantage can be said that steel radiators can be covered by corrosion in the presence of air in the coolant, so the system should always be deflated.
Many people are advised to pay attention to aluminum radiators. However, if the choice of heating radiators for a private home for you has a limited budget, it is better to choose steel radiators. Since aluminum radiators need to remove air from the top manifold with an air vent valve, and suffocating radiators can be quite active due to the chemical reactions of the coolant with aluminum. The second significant disadvantage of aluminum radiators can be called. weak resistance to corrosion. The activity of aluminum does not allow long operation of the device in standard heating conditions. To prolong its service life can be used the sparing heat-carrier (pH 7-8). Specially prepared water should not contain solid particles that can destroy the protective film on the inner surface of the radiator.
In this category, both materials have both pluses and minuses. The main disadvantage of cast iron is that it takes a very long time to heat up. But this is compensated by the fact that it also cools for a long time. The advantage of such batteries is that they heat the room by convection heat as well as by radiant heat. Cast iron radiator transmits heat to all neighboring items. One section of the cast iron construction produces a capacity of 100 to 160 watts.
As for the bimetallic radiators, their heat emission index is also high. They heat up almost instantly, but also cool down in the same way. The heat output of one section of a bimetallic radiator is higher than that of cast iron devices. It is 150-200 Watt.
Therefore, in order to choose the right radiator, you must first take into account the characteristics of the room in which it will be installed. If the house has no problems with the supply of the coolant, the process is carried out stably without interruptions, it is advisable to install bimetallic batteries.
If the advantages of cast-iron batteries outweigh their disadvantages for you, we can recommend qualitative modern cast-iron batteries. In “Santekhbomba” store you’ll find several practical variants. you’ll find STI Nova 500 and STI Nova 300 models. They differ from each other in size and power characteristics. so, the “senior” model 500 has a heat output of 150 watts per section, the weight of the section is 4.2 kg, volume. 0.52 l. Model 300 has 120 W, 2.9 kg and 0.3 l volume and is 20 cm lower. Both radiators are characterized by their original design and are surface-coated with a temperature-resistant polymer coating.
For those who like the familiar design, the classic model MC-140 is a good choice. Consisting of 7 sections of 150 W each it looks almost the same as “those very” Soviet batteries. And, of course, it’s still heavy, since it’s made of real cast iron. By the way, you have not forgotten what advantages this material has?
Замена чугунной батареи на биметаллическую. Установка биметаллического радиатора отопления. Легко!
Pros and cons of bimetallic radiators
The heating system is one of the most important aspects, which determines the comfort of being in the house. It is with its proper installation and adjustment, the heat output will be high, and the percentage of energy loss will be minimal. But in addition to these parameters you should also pay attention to the choice of the radiator. its characteristics determine the final efficiency and durability of the system.
The priority in this segment have bimetallic heating batteries: the sizes and types of these solutions are varied, and the parameters are the most acceptable for all possible scenarios of use. The installation of this type of radiators is appropriate for both residential areas (private homes and apartments), as well as for offices.
Combining the advantages of other types of batteries, bimetallic solutions look attractive from both a practical and financial point of view. They will save money on utility bills, as well as on maintenance of the system. But do these radiators have their own drawbacks and how critical they are? This article will help you decide what to choose.
Heat output of cast iron and bimetal
The power of heating by radiators, indicated by the manufacturers, rarely corresponds to reality. It depends on the temperature of the coolant and the air in the room. On average, the heat output of one section with a height of 50 cm is:
- Cast iron. 140-195 W (depending on depth);
- Bimetal without air strippers. 140-155 W;
- Bimetal with air strippers. 170-190 W.
It is worth noting that cast iron heats very slowly, but also cools down for a long time. Bimetallic radiators do it much faster. Cast iron radiators allow you to keep the temperature in case of heating failure.
The heating of the room with cast iron radiators is mainly due to radiation, not convection. With bimetallic ones, it’s through convection. So they quickly heat up the air in the room.
The quality of the coolant
The water supplied to the batteries is most often not of good quality, it may contain such elements:
All of these have an abrasive effect on the heaters. It is worth considering how these deficiencies affect the two types of radiators:
- Cast iron radiators are not affected by increased alkalinity and acidity. The batteries have thick enough walls, which can withstand corrosion for a long time. It is removed with the water when the cleaning work is done in the summer. And the abrasive elements can rub off the metal a little bit. However, again due to the thick walls these changes are not perceptible.
- Chemically active composition of the coolant does little harm to the bimetal radiator, too. However, when draining the water in them air appears due to which the metal core rusts.
In this case, you may conclude that cast iron heaters are better able to withstand corrosion.