Every home owner is faced with important questions when installing heating. What kind of radiator should you choose? How to calculate the number of radiator sections? If a house is being built for you by professional staff, they will help you make the correct calculations so that the distribution of heating batteries in the building is rational. However, this procedure can be carried out independently. The formulas required for this can be found below in the article.

Types of radiators

Today there are such types of batteries for heating: bimetallic, steel, aluminum and cast iron. Also, radiators are divided into panel, sectional, convector, tubular, and also design radiators. Their choice depends on the coolant, the technical capabilities of the heating system and the financial capabilities of the owner of the house. How to calculate the number of radiator sections per room? It does not depend on the type. In this case, only one indicator is taken into account - the radiator power.

Calculation methods

In order for the heating system in the room to work efficiently and in winter it was warm and comfortable in it, you need to carefully.For this, the following calculation methods are used:

• Standard - carried out on the basis of the provisions of SNiP, according to which heating 1m 2 will require a power of 100 watts. The calculation is carried out using the formula: S / P, where P is the capacity of the department, S is the area of ​​the selected room.
• Approximate - to heat a 1.8 m 2 apartment with ceilings 2.5 m high, one radiator section will be needed.
• Volumetric method - heating power 41 W is taken for 1m 3. The width, height and length of the room are taken into account.

How many radiators do you need for the whole house

How to calculate the number of radiator sections for an apartment or house? The calculation is carried out for each room separately. According to the standard, the thermal power per 1m 3 of the volume of a room that has one door, a window and an external wall is considered to be 41 W.

If the house or apartment is "cold", with thin walls, has many windows, and the apartment is located on the first or last floor in the house, then 47 W per 1m 3 are needed to heat them, and not 41 W. For a house built of modern materials using different insulation materials for walls, floors, ceilings, with metal-plastic windows. you can take 30 watts.

To replace cast-iron radiators, there is the simplest calculation method: you need to multiply their number by the resulting number - the power of new devices. When purchasing aluminum or bimetallic batteries for replacement, the calculation is carried out in the ratio: one cast iron edge to one aluminum one.

Rules for calculating the number of branches

• An increase in the radiator power occurs: if the room is front and has one window - by 20%; with two windows - by 30%; windows facing north also require an increase of another 10%; installing the battery under the window - 5%; covering the heater with a decorative screen - by 15%.
• The power required for heating can be calculated by multiplying the area of ​​the room (in m 2) by 100 W.

In the passport for the products, the manufacturer indicates the specific power, which makes it possible to calculate the proper number of sections. Do not forget that heat transfer is affected by the power of a separate section, and not by the size of the radiator. Therefore, placing and installing several small appliances in a room is more effective than installing one large one. The incoming heat from different sides will warm it up evenly.

Calculating the number of bimetallic battery compartments

• Dimensions of the room and the number of windows in it.
• The location of a particular room.
• The presence of openings, arches and doors.
• Heat transfer power of each section, indicated by the manufacturer in the passport.

Calculation stages

How to calculate the number of radiator sections if all the necessary data is recorded? To do this, determine the area, calculating in meters the derivatives of the width and height of the room. Using the formula S = L x W, calculate the joint area if they have open openings or arches.

Next, the total batteries are calculated (P = S x 100), using a power of 100 W to heat one m 2. Then calculate the proper number of sections (n ​​= P / Pc) by dividing the total thermal power by the heat transfer of one section indicated in the passport.

Depending on the location of the premises, the calculation of the required number of compartments of the bimetallic device is carried out taking into account the correction factors: 1.3 - for angular; use a coefficient of 1.1 - for the first and last floors; 1,2 - used for two windows; 1.5 - three or more windows.

Calculation of battery sections in the end room, located on the first floor of the house and having 2 windows. The dimensions of the room are 5 x 5 m. The heat transfer of one section is 190 W.

• We calculate the area of ​​the room: S = 5 x 5 = 25 m 2.
• We calculate the thermal power in general: P = 25 x 100 = 2500 W.
• We calculate the required sections: n = 2500/190 = 13.6. Rounding up, we get 14. We take into account the correction factors n = 14 x 1.3 x 1.2 x 1.1 = 24.024.
• We divide the sections into two batteries and install them under the windows.

We hope that the information in the article will tell you how to calculate the number of radiator sections for a home. To do this, use the formulas and make a relatively accurate calculation. It is important to choose the right section power that is suitable for your heating system.

If you cannot independently calculate the required number of batteries for your home, it is best to seek help from specialists. They will make a competent calculation, taking into account all the factors affecting the efficiency of the installed heating devices, which will provide heat in the house during the cold period.

One of the most important issues in creating comfortable living conditions in a house or apartment is a reliable, correctly calculated and installed, well-balanced heating system. That is why the creation of such a system is the most important task when organizing the construction of your own house or when carrying out major repairs in an apartment of a high-rise building.

Despite the modern variety of heating systems of various types, the proven scheme remains the leader in popularity: pipe circuits with a coolant circulating through them, and heat exchange devices - radiators installed in the premises. It would seem that everything is simple, the batteries are under the windows and provide the required heating ... However, you need to know that the heat transfer from the radiators must correspond to the area of ​​the room and a number of other specific criteria. Thermal calculations based on the requirements of SNiP is a rather complicated procedure performed by specialists. Nevertheless, you can do it on your own, of course, with an acceptable simplification. This publication will tell you how to independently calculate the heating batteries for the area of ​​the heated room, taking into account various nuances.

But, for a start, you need to at least briefly familiarize yourself with the existing heating radiators - the results of the calculations will largely depend on their parameters.

Briefly about the existing types of heating radiators

• Steel radiators of panel or tubular construction.
• Cast iron batteries.
• Aluminum radiators of several modifications.
• Bimetallic radiators.

Steel radiators

This type of radiator has not gained much popularity, despite the fact that some models are given a very elegant design. The problem is that the disadvantages of such heat exchange devices significantly exceed their advantages - low price, relatively small weight and ease of installation.

The thin steel walls of such radiators do not have enough heat - they quickly heat up, but also cool down just as rapidly. Problems can also arise during water hammer - the welded joints of the sheets sometimes leak. In addition, inexpensive models that do not have a special coating are prone to corrosion, and the service life of such batteries is short - usually manufacturers give them a rather short warranty.

In the overwhelming majority of cases, steel radiators are an integral structure, and it is not possible to vary the heat transfer by changing the number of sections. They have a rated thermal power, which must be immediately selected based on the area and characteristics of the room where they are planned to be installed. The exception is that some tubular radiators have the ability to change the number of sections, but this is usually done on order, during manufacture, and not at home.

Cast iron radiators

Representatives of this type of batteries are probably familiar to everyone from early childhood - these are the kind of accordions that were previously installed literally everywhere.

Perhaps such MC-140-500 batteries did not differ in particular elegance, but they faithfully served more than one generation of residents. Each section of such a radiator provided a heat transfer of 160 watts. The radiator is prefabricated, and the number of sections, in principle, was not limited by anything.

Currently, there are many modern cast iron radiators on sale. They are already distinguished by a more elegant appearance, flat, smooth outer surfaces that make cleaning easier. Exclusive versions are also produced, with an interesting relief pattern of cast iron casting.

With all this, such models fully retain the main advantages of cast iron batteries:

• The high heat capacity of cast iron and the massiveness of the batteries contribute to long-term retention and high heat transfer.
• Cast iron batteries, with proper assembly and high-quality sealing of joints, are not afraid of water hammer, temperature changes.
• Thick cast iron walls are not susceptible to corrosion and abrasion. Almost any heat carrier can be used, so such batteries are equally good for both autonomous and central heating systems.

If you do not take into account the external data of old cast-iron batteries, then among the shortcomings can be noted the fragility of the metal (accented blows are unacceptable), the relative complexity of installation, associated more with massiveness. In addition, not all wall partitions will be able to support the weight of such radiators.

Aluminum radiators

Aluminum radiators, having appeared relatively recently, very quickly gained popularity. They are relatively inexpensive, have a modern, rather elegant appearance, and have excellent heat dissipation.

High-quality aluminum batteries can withstand a pressure of 15 or more atmospheres, a high coolant temperature - about 100 degrees. At the same time, the heat output from one section for some models sometimes reaches 200 W. But at the same time, they are small in mass (the weight of the section is usually up to 2 kg) and do not require a large volume of coolant (capacity - no more than 500 ml).

Aluminum radiators are on sale both as stackable batteries, with the ability to change the number of sections, and as solid products designed for a certain power.

Disadvantages of aluminum radiators:

• Some types are highly susceptible to oxygen corrosion of aluminum, with a high risk of gassing. This imposes special requirements on the quality of the coolant, therefore, such batteries are usually installed in autonomous heating systems.
• Some non-separable aluminum radiators, whose sections are manufactured using extrusion technology, can leak at the joints under certain unfavorable conditions. At the same time, it is simply impossible to carry out repairs, and you will have to change the entire battery as a whole.

Of all the aluminum batteries, the highest quality is made with the use of anodic oxidation of the metal. These products are practically not afraid of oxygen corrosion.

Outwardly, all aluminum radiators are roughly similar, so you need to read the technical documentation very carefully when making a choice.

Bimetallic heating radiators

Such radiators in their reliability compete with cast iron, and in terms of heat output - with aluminum. The reason for this is their special design.

Each of the sections consists of two, upper and lower, steel horizontal collectors (item 1), connected by the same steel vertical channel (item 2). The connection into a single battery is made with high quality threaded couplings (pos. 3). High heat dissipation is ensured by the outer aluminum shell.

Steel inner pipes are made of metal that does not corrode or has a protective polymer coating. Well, the aluminum heat exchanger does not come into contact with the coolant under any circumstances, and corrosion is absolutely not terrible for it.

Thus, a combination of high strength and wear resistance with excellent thermal performance is obtained.

Prices for popular heating radiators

Heating radiators

Such batteries are not afraid of even very large pressure surges, high temperatures. They are, in fact, universal, and are suitable for any heating systems, however, they still show the best performance characteristics in conditions of high pressure of the central system - they are of little use for circuits with natural circulation.

Perhaps their only drawback is the high price compared to any other radiators.

For ease of perception, there is a table showing the comparative characteristics of radiators. Symbols in it:

• TS - tubular steel;
• Chg - cast iron;
• Al - ordinary aluminum;
• AA - anodized aluminum;
• BM - bimetallic.

	Chg	TS	Al	AA	BM
Maximum pressure (atmospheres)
working	6-9	6-12	10-20	15-40	35
crimping	12-15	9	15-30	25-75	57
destruction	20-25	18-25	30-50	100	75
Limitation on pH (hydrogen index)	6,5-9	6,5-9	7-8	6,5-9	6,5-9
Corrosion susceptibility by:
oxygen	No	Yes	No	No	Yes
stray currents	No	Yes	Yes	No	Yes
electrolytic vapors	No	weak	Yes	No	weak
Section capacity at h = 500 mm; Dt = 70 °, W	160	85	175-200	216,3	up to 200
Warranty, years	10	1	3-10	30	3-10

Video: recommendations for choosing heating radiators

You may be interested in information about what constitutes

How to calculate the required number of heating radiator sections

It is clear that a radiator installed in the room (one or more) must provide heating to a comfortable temperature and compensate for the inevitable heat loss, regardless of the weather outside.

The base value for calculations is always the area or volume of the room. By themselves, professional calculations are very complex, and take into account a very large number of criteria. But for everyday needs, you can use simplified methods.

The easiest ways to calculate

It is generally accepted that 100 W per square meter of floor space is sufficient to create normal conditions in a standard living space. Thus, you just need to calculate the area of ​​the room and multiply it by 100.

Q = S× 100

Q- the required heat transfer from heating radiators.

S- the area of ​​the heated room.

If you plan to install a non-separable radiator, then this value will become a guideline for the selection of the required model. In the case when batteries will be installed that allow a change in the number of sections, one more calculation should be carried out:

N = Q/ Qus

N- the calculated number of sections.

Qus- specific thermal power of one section. This value is necessarily indicated in the technical passport of the product.

As you can see, these calculations are extremely simple, and do not require any special knowledge of mathematics - a tape measure is enough to measure a room and a piece of paper for calculations. In addition, you can use the table below - there are already calculated values ​​for rooms of various sizes and certain capacities of the heating sections.

Section table

However, it must be remembered that these values ​​are for a standard ceiling height (2.7 m) of a high-rise building. If the height of the room is different, then it is better to calculate the number of battery sections based on the volume of the room. For this, an average indicator is applied - 41 V t t thermal power per 1 m³ of volume in a panel house, or 34 W - in a brick one.

Q = S × h× 40 (34)

where h- ceiling height above floor level.

Further calculation is no different from the one presented above.

Detailed calculation taking into account the features premises

Now let's move on to more serious calculations. The simplified calculation technique given above can give the owners of a house or apartment a "surprise". When the installed radiators will not create the required comfortable microclimate in the living quarters. And the reason for this is a whole list of nuances that the considered method simply does not take into account. Meanwhile, such nuances can be very important.

So, the area of ​​the room is again taken as a basis and all the same 100 W per m². But the formula itself already looks somewhat different:

Q = S× 100 × A × B × C ×D× E ×F× G× H× I× J

Letters from A before J the coefficients are conventionally designated, taking into account the features of the room and the installation of radiators in it. Let's consider them in order:

A is the number of external walls in the room.

It is clear that the higher the area of ​​contact between the room and the street, that is, the more external walls in the room, the higher the total heat loss. This dependence is taken into account by the coefficient A:

• One outer wall - A = 1.0
• Two outer walls - A = 1.2
• Three outer walls - A = 1.3
• All four walls are external - A = 1.4

B - orientation of the room to the cardinal points.

The maximum heat loss is always in rooms that do not receive direct sunlight. This is, of course, the northern side of the house, and the eastern side can also be attributed here - the rays of the Sun are here only in the morning, when the luminary has not yet “reached full power”.

The southern and western sides of the house are always warmed up by the Sun much more strongly.

Hence, the values ​​of the coefficient V :

• The room faces north or east - B = 1.1
• South or west rooms - B = 1, that is, it may not be counted.

C is a coefficient that takes into account the degree of wall insulation.

It is clear that the heat loss from the heated room will depend on the quality of the thermal insulation of the outer walls. Coefficient value WITH take equal:

• Middle level - the walls are lined with two bricks, or their surface insulation with another material is provided - C = 1.0
• External walls are not insulated - C = 1.27
• A high level of insulation based on thermal engineering calculations - C = 0.85.

D - features of the climatic conditions of the region.

Naturally, it is impossible to equal all the basic indicators of the required heating power "one size fits all" - they also depend on the level of winter temperatures below zero, typical for a particular area. This takes into account the coefficient D. To select it, the average temperatures of the coldest decade of January are taken - usually this value is easy to check with the local hydrometeorological service.

• - 35 ° WITH and below - D = 1.5
• - 25 ÷ - 35 ° WITH – D = 1.3
• up to - 20 ° WITH – D = 1.1
• not lower - 15 ° WITH – D = 0.9
• not lower - 10 ° WITH – D = 0.7

E - coefficient of the height of the ceilings of the room.

As already mentioned, 100 W / m² is the average value for a standard ceiling height. If it differs, you should enter a correction factor E:

• Up to 2.7 m – E = 1,0
• 2,8 – 3, 0 m – E = 1,05
• 3,1 – 3, 5 m – E = 1, 1
• 3,6 – 4, 0 m – E = 1.15
• More than 4.1 m - E = 1.2

F - coefficient taking into account the type of premises located above

Arranging a heating system in rooms with a cold floor is a pointless exercise, and the owners always take action in this matter. But the type of room located above, often does not depend on them in any way. Meanwhile, if the top is a residential or insulated room, then the total demand for thermal energy will significantly decrease:

• cold attic or unheated room - F = 1.0
• insulated attic (including - and insulated roof) - F = 0.9
• heated room - F = 0.8

G - coefficient of account of the type of installed windows.

Different window structures are not equally susceptible to heat loss. This takes into account the coefficient G:

• ordinary wooden frames with double glazing - G = 1.27
• windows are equipped with a single-chamber double-glazed window (2 glasses) - G = 1.0
• single-chamber glass unit with argon filling or double glass unit (3 glasses) - G = 0.85

H - coefficient of the area of ​​the glazing of the room.

The total amount of heat loss also depends on the total area of ​​the windows installed in the room. This value is calculated based on the ratio of the area of ​​the windows to the area of ​​the room. Depending on the result obtained, we find the coefficient N:

• Ratio less than 0.1 - H = 0, 8
• 0.11 ÷ 0.2 - H = 0, 9
• 0.21 ÷ 0.3 - H = 1, 0
• 0.31 ÷ 0.4 - H = 1, 1
• 0.41 ÷ 0.5 - H = 1.2

I - coefficient taking into account the radiator connection diagram.

Their heat transfer depends on how the radiators are connected to the supply and return pipes. This should also be taken into account when planning the installation and determining the required number of sections:

• a - diagonal connection, supply from above, return from below - I = 1.0
• b - one-way connection, supply from above, return from below - I = 1.03
• c - two-way connection, both supply and return from the bottom - I = 1.13
• d - diagonal connection, supply from below, return from above - I = 1.25
• d - one-way connection, supply from below, return from above - I = 1.28
• e - one-sided bottom connection of return and supply - I = 1.28

J - coefficient taking into account the degree of openness of the installed radiators.

Much also depends on how open the installed batteries are for free heat exchange with the room air. Existing or artificially created barriers can significantly reduce the heat transfer of the radiator. This takes into account the coefficient J:

a - the radiator is located openly on the wall or not covered by a window sill - J = 0.9

b - the radiator is covered from above with a window sill or shelf - J = 1.0

c - the radiator is covered from above with a horizontal protrusion of the wall niche - J = 1.07

d - the radiator is covered from above with a window sill, and from the front parties — partswell covered with a decorative cover - J = 1.12

e - the radiator is completely covered with a decorative casing - J = 1.2

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Well, finally, that's all. Now you can substitute the required values ​​and the coefficients corresponding to the conditions into the formula, and the output will be the required thermal power for reliable heating of the room, taking into account all the nuances.

After that, it will remain either to pick up a non-separable radiator with the desired heat output, or to divide the calculated value by the specific thermal power of one section of the battery of the selected model.

Surely, to many, such a calculation will seem excessively cumbersome, in which it is easy to get confused. To facilitate the calculations, we suggest using a special calculator - all the required values ​​are already included in it. The user only needs to enter the requested initial values ​​or select the required items from the lists. The "calculate" button will immediately lead to an accurate result rounded up.

In order to always be warm and cozy in the house during the cold season, it is very important to be able to correctly calculate the required number of heating radiator sections. Stores offer many different models that come in a variety of shapes and characteristics. When purchasing a radiator for a house or apartment, you must take into account all the pros and cons of the model.

Any owner of a house or apartment wanted the room to be always warm and comfortable.

Radiators: types

In the modern market, you can find not only the familiar cast-iron heating batteries, but also completely new models that are made of steel or aluminum... There are also bimetallic radiators.

• Tubular batteries are considered expensive models. They heat up longer than panel ones. Naturally, they also retain heat longer.
• Panel radiators are fast heating radiators. Their price is lower than the cost of tubular models. However, these batteries cool very quickly and are therefore considered uneconomical.

In order to design a good heating system in the house, it is important to take into account the characteristics of radiators, their placement in rooms, the number and other factors that affect the preservation of heat in the room.

Calculation taking into account the area of ​​the room

Based on the size of the area of ​​the room, you can make a preliminary calculation. The calculations are simple, they are suitable for rooms with low ceilings (2.4 - 2.6 m). To heat each meter of the room, you need 100 watts. power.

When calculating, you must always take into account the possible heat loss according to specific situations. So, in a corner room or in a room with a balcony, heat is lost faster. For these premises, the heat output must be increased by 20%. It is also worth increasing this value for rooms in which radiators are planned to be built into a niche or covered with a screen.

Calculation taking into account the volume of the room

For more accurate calculations in calculations it is worth considering the height of the vault of the room... The principle of calculations is similar to that indicated above: we calculate the total amount of required heat, and, then, we find the number of radiator sections.

Based on building codes for heating 1 kb. m. of the premises of a panel house, a thermal power of 41 watts is required. Find the volume of a room by multiplying its area by its height. The result is multiplied by the above rate and we get the total amount of heat required for heating. If the apartment is modern and has double-glazed windows, then the normalized value can be taken less - 34 W per 1 cu. m.

As an example, let's make a calculation for a room with an area of ​​20 sq. m. and a height of 3 m.

1. Find the volume of the room by multiplying the area by the height: 20 sqm x 3 m = 60 cubic meters m.
2. To heat a room, you need power: 60 cc mx 41 W = 2460 W.
3. To calculate the number of radiator sections, we take the heat transfer value of one section from the first case - 170 W. Thus, 2460 W / 170 W = 14.47, round up to 15 sections.

It is worth noting that many manufacturers of heating radiators give overestimated values ​​in technical documentation. Which means the values ​​indicated in the data sheet should be treated as maximum values... Knowing and considering this, in the calculations, you can make the readings of the calculations more realistic.

Accurate calculation using coefficients

Not every room can boast of a standard layout. And the layout of a private house is purely individual. In this case, it is good to use even more accurate calculations. The method is based on finding a very accurate value of the required amount of heat to heat the room. After finding this value, the already familiar operation is carried out to calculate the number of heating radiator sections.

Kt = 100 W / m2 x Pl x Kf1 x Kf 2 x Kf 3 x Kf4 x Kf5 x Kf6 x Kf7.

• Pl is the area of ​​the room;
• Кт - the amount of heat required to heat it;
• Кф1 - coefficient of glazing of windows.

It takes the following values:

• 1.27 - for ordinary double glazed windows;
• 1.0 - for double glazing;
• 0.85 - for triple glazing.

Kf2 is a coefficient that takes into account the thermal insulation of the walls.

Accepts values:

• 1.27 - for a low degree of thermal insulation;
• 1.0 - for medium thermal insulation (if there is double masonry or the walls are lined with insulation);
• 0.85 - for a high degree of thermal insulation.

Kf3 is a coefficient that takes into account the ratio of the area of ​​the floor and windows and the floor in the room.

Has the following meanings:

• 1.2 - at 50%;
• 1.1 - at 40%;
• 1.0 - at 30%;
• 0.9 - at 20%;
• 0.8 - at 10%.

Kf4 is a coefficient that takes into account the average air temperature in the coldest week of the year.

Possible values:

• 1.5 - at -35 degrees;
• 1.3 - at -25 degrees.;
• 1.1. - at -20 degrees;
• 0.9 - at -15 degrees;
• 0.7 - at -10 deg.

Kf5 is a coefficient that corrects heat demand based on the number of external walls.

Accepts values:

• 1.1 - if there is 1 wall;
• 1.2 - if there are 2 walls;
• 1.3 - if there are 3 walls;
• 1.4 - if there are 4 walls.

Kf6 is a coefficient that takes into account the type of room located above the room.

Accepts values:

• 1.0 - in the presence of a cold attic;
• 0.9 - in the presence of a heated attic;
• 0.8 - in the presence of a heated living space.

Kf7 is a coefficient that takes into account the height of the ceiling in the room.

It takes the following values:

• 1.0 - height 2.5 m.;
• 1.05 - height 3.0 m.;
• 1.1 - height 3.5 m.;
• 1.15 - height 4.0 m.;
• 1.2 - height 4.5 m.

This calculation, taking into account all the nuances, gives a very accurate result of the amount of heat required to heat a room.

Having performed the calculation and having obtained the exact value of Kt, we divide it by the value of the heat output of one section (we take the value from the data sheet of the model) and we get the exact number of required sections heating radiators.

You can use any of the three calculation methods, they differ only in the accuracy of calculating the thermal power. Don't be afraid to waste time calculating if you want to spend long winter evenings in warmth and comfort.

There are several methods for calculating the number of radiators, but their essence is the same: find out the maximum heat loss in a room, and then calculate the number of heating devices required to compensate them.

There are different calculation methods. The simplest ones give approximate results. Nevertheless, they can be used if the premises are standard or apply coefficients that allow taking into account the existing "non-standard" conditions of each particular room (corner room, exit to the balcony, full-wall window, etc.). There is a more complex calculation using the formulas. But in fact, these are the same coefficients, only collected in one formula.

There is one more method. It determines the actual losses. A special device - a thermal imager - determines the real heat loss. And on the basis of these data, they calculate how many radiators are needed to compensate them. What's more good about this method is that the thermal imager clearly shows where the heat is most actively removed. It can be a defect in work or building materials, a crack, etc. So at the same time, you can straighten out the situation.

Calculation of heating radiators by area

The easiest way. Calculate the amount of heat required for heating, based on the area of ​​the room in which the radiators will be installed. You know the area of ​​each room, and the heat demand can be determined according to the building codes SNiP:

• for the middle climatic zone, 60-100W is required for heating 1m 2 of living space;
• for areas above 60 o, 150-200W are required.

Based on these norms, you can calculate how much heat your room will require. If the apartment / house is located in the middle climatic zone, for heating an area of ​​16m 2, 1600W of heat will be required (16 * 100 = 1600). Since the norms are average, and the weather does not indulge in constancy, we believe that 100W is required. Although, if you live in the south of the middle climatic zone and your winters are mild, count 60W.

A power reserve in heating is needed, but not very large: with an increase in the amount of required power, the number of radiators increases. And the more radiators, the more coolant in the system. If for those who are connected to central heating this is not critical, then for those who have or are planning individual heating, a large volume of the system means large (extra) costs for heating the coolant and a greater inertia of the system (the set temperature is less accurately maintained). And a logical question arises: "Why pay more?"

Having calculated the heat demand of the room, we can find out how many sections are required. Each of the heating devices can emit a certain amount of heat, which is indicated in the passport. They take the found heat demand and divide it by the radiator power. The result is the required number of sections to make up for losses.

Let's calculate the number of radiators for the same room. We have determined that 1600W is required. Let the power of one section be 170W. It turns out 1600/170 = 9.411 pcs. You can round up or down at your discretion. It can be rounded into a smaller one, for example, in a kitchen - there are enough additional sources of heat, and in a larger one - it is better in a room with a balcony, a large window or in a corner room.

The system is simple, but the disadvantages are obvious: the height of the ceilings can be different, the material of the walls, windows, insulation and a number of other factors are not taken into account. So the calculation of the number of heating radiator sections according to SNiP is approximate. For an accurate result, you need to make adjustments.

How to calculate radiator sections by room volume

With this calculation, not only the area is taken into account, but also the height of the ceilings, because all the air in the room needs to be heated. So this approach is justified. And in this case, the technique is similar. We determine the volume of the room, and then, according to the norms, we find out how much heat is needed to heat it:

Let's calculate everything for the same room with an area of ​​16m 2 and compare the results. Let the ceiling height be 2.7m. Volume: 16 * 2.7 = 43.2m 3.

• In a panel house. Heat required for heating 43.2m 3 * 41V = 1771.2W. If we take all the same sections with a power of 170W, we get: 1771W / 170W = 10.418 pieces (11 pieces).
• In a brick house. Heat is needed 43.2m 3 * 34W = 1468.8W. We count radiators: 1468.8W / 170W = 8.64pcs (9pcs).

As you can see, the difference turns out to be quite large: 11 pieces and 9 pieces. Moreover, when calculating by area, an average value was obtained (if rounded in the same direction) - 10 pieces.

Adjustment of results

In order to get a more accurate calculation, you need to take into account as many factors as possible that reduce or increase heat loss. This is what the walls are made of and how well they are insulated, how large the windows are, and what kind of glazing is on them, how many walls in the room face the street, etc. For this, there are coefficients by which the found values ​​of the heat loss of the room must be multiplied.

Window

Windows account for 15% to 35% of heat loss. The specific figure depends on the size of the window and on how well it is insulated. Therefore, there are two corresponding coefficients:

• ratio of window area to floor area:
  • 10% — 0,8
  • 20% — 0,9
  • 30% — 1,0
  • 40% — 1,1
  • 50% — 1,2
• glazing:
  • three-chamber double-glazed window or argon in a two-chamber double-glazed window - 0.85
  • ordinary double-glazed window - 1.0
  • conventional double frames - 1.27.

Walls and roof

To account for losses, the material of the walls, the degree of thermal insulation, the number of walls facing the street are important. Here are the coefficients for these factors.

Thermal insulation degree:

• brick walls two bricks thick are considered the norm - 1.0
• insufficient (absent) - 1.27
• good - 0.8

The presence of external walls:

• indoor space - no losses, coefficient 1.0
• one - 1.1
• two - 1.2
• three - 1.3

The amount of heat loss is influenced by whether or not the room is heated above. If there is an inhabited heated room on top (second floor of a house, another apartment, etc.), the decreasing coefficient is 0.7, if the heated attic is 0.9. It is generally accepted that an unheated attic does not in any way affect the temperature in and (coefficient 1.0).

If the calculation was carried out by area, and the height of the ceilings is non-standard (a height of 2.7 m is taken as the standard), then a proportional increase / decrease using a coefficient is used. It is considered easy. To do this, divide the real height of the ceilings in the room by the standard 2.7 m. You get the required coefficient.

Let's calculate for example: let the ceiling height be 3.0 m. We get: 3.0m / 2.7m = 1.1. This means the number of radiator sections, which was calculated by the area for a given room, must be multiplied by 1.1.

All these norms and factors were determined for apartments. To take into account the heat loss of the house through the roof and basement / foundation, you need to increase the result by 50%, that is, the coefficient for a private house is 1.5.

Climatic factors

Adjustments can be made based on average winter temperatures:

• -10 o C and above - 0.7
• -15 o C - 0.9
• -20 o C - 1.1
• -25 o C - 1.3
• -30 o C - 1.5

Having made all the necessary adjustments, you will get a more accurate number of radiators required for heating a room, taking into account the parameters of the premises. But this is not all the criteria that affect the power of thermal radiation. There are also technical subtleties, which we will discuss below.

Calculation of different types of radiators

If you are going to install sectional radiators of a standard size (with an axial distance of 50 cm in height) and have already chosen the material, model and the required size, there should be no difficulty in calculating their number. Most reputable companies supplying good heating equipment have technical data for all modifications on their website, among which there is a thermal power. If it is not power that is indicated, but the flow rate of the coolant, then it is simple to translate into power: the flow rate of the coolant in 1 l / min is approximately equal to the power of 1 kW (1000 W).

The axial distance of the radiator is determined by the height between the centers of the holes for the supply / return of the coolant.

To make life easier for buyers, a specially designed calculator program is installed on many sites. Then the calculation of heating radiator sections is reduced to entering data on your room in the appropriate fields. And at the output you have a finished result: the number of sections of this model in pieces.

But if you are just thinking about possible options, then it should be borne in mind that radiators of the same size from different materials have different thermal power. The method for calculating the number of sections of bimetallic radiators is no different from calculating aluminum, steel or cast iron. Only the heat output of one section can be different.

• aluminum - 190W
• bimetallic - 185W
• cast iron - 145W.

If you are just wondering which of the materials to choose, you can use this data. For clarity, we present the simplest calculation of sections of bimetallic heating radiators, which takes into account only the area of ​​the room.

When determining the number of heating devices made of bimetal of standard size (center-to-center distance 50cm), it is assumed that one section can heat 1.8m 2 of area. Then for a room of 16m 2 you need: 16m 2 / 1.8m 2 = 8.88 pcs. Rounding up - 9 sections are needed.

We consider the same for cast iron or steel barriers. We only need norms:

• bimetallic radiator - 1.8m 2
• aluminum - 1.9-2.0m 2
• cast iron - 1.4-1.5m 2.

This data is for sections with a center distance of 50cm. Today, there are models on sale with very different heights: from 60cm to 20cm and even lower. Models 20cm and below are called curbs. Naturally, their capacity differs from the specified standard, and if you plan to use a "non-standard", you will have to make adjustments. Either look for passport data, or count yourself. We proceed from the fact that the heat transfer of a heating device directly depends on its area. With a decrease in height, the area of ​​the device decreases, and, therefore, the power decreases proportionally. That is, you need to find the ratio of the heights of the selected radiator to the standard, and then use this coefficient to correct the result.

For clarity, we will calculate the area of ​​aluminum radiators. The room is the same: 16m 2. We count the number of sections of a standard size: 16m 2 / 2m 2 = 8pcs. But we want to use small sections with a height of 40cm. We find the ratio of radiators of the selected size to the standard ones: 50cm / 40cm = 1.25. And now we adjust the quantity: 8pcs * 1.25 = 10pcs.

Correction depending on the mode of the heating system

Manufacturers in the passport data indicate the maximum power of the radiators: in high-temperature mode of use - the temperature of the coolant in the supply is 90 ° C, in the return line - 70 ° C (denoted by 90/70), the room should be 20 ° C. But in this mode, modern systems heating systems work very rarely. Typically, a medium power mode of 75/65/20 is used, or even a low-temperature mode with parameters 55/45/20. It is clear that the calculation needs to be corrected.

To take into account the operating mode of the system, it is necessary to determine the temperature difference of the system. Temperature head is the difference between the temperature of the air and the heaters. In this case, the temperature of the heaters is considered as the arithmetic mean between the flow and return values.

To make it clearer, we will calculate cast-iron heating radiators for two modes: high-temperature and low-temperature, sections of a standard size (50cm). The room is the same: 16m 2. One cast-iron section in high-temperature mode 90/70/20 heats 1.5m 2. Therefore, we need 16m 2 / 1.5m 2 = 10.6 pcs. Round off - 11pcs. It is planned to use the low temperature mode 55/45/20 in the system. Now we will find the temperature difference for each of the systems:

• high-temperature 90/70 / 20- (90 + 70) / 2-20 = 60 о С;
• low-temperature 55/45/20 - (55 + 45) / 2-20 = 30 о С.

That is, if a low-temperature operating mode is used, twice as many sections will be needed to provide the room with heat. For our example, a room of 16m 2 requires 22 sections of cast iron radiators. The battery turns out to be large. This, by the way, is one of the reasons why this type of heating device is not recommended for use in networks with low temperatures.

With this calculation, the desired air temperature can also be taken into account. If you want the room to be not 20 ° C, but, for example, 25 ° C, just calculate the thermal head for this case and find the required coefficient. Let's do the calculation for the same cast-iron radiators: the parameters will be 90/70/25. We consider the temperature head for this case (90 + 70) / 2-25 = 55 о С. Now we find the ratio 60 о С / 55 о С = 1.1. To provide a temperature of 25 ° C, you need 11pcs * 1.1 = 12.1pcs.

Dependence of the power of radiators on the connection and location

In addition to all the parameters described above, the heat dissipation of the radiator varies depending on the type of connection. A diagonal connection with a supply from above is considered optimal, in which case there is no heat loss. The largest losses are observed with lateral connection - 22%. All the rest are average in terms of efficiency. The approximate percentage loss values ​​are shown in the figure.

The actual power of the radiator also decreases in the presence of barriers. For example, if a window sill hangs from above, the heat transfer drops by 7-8%, if it does not completely cover the radiator, then the losses are 3-5%. When installing a mesh screen that does not reach the floor, the losses are about the same as in the case of an overhanging window sill: 7-8%. But if the screen completely covers the entire heating device, its heat transfer decreases by 20-25%.

Determination of the number of radiators for one-pipe systems

There is one more very important point: all of the above is true for when a coolant with the same temperature enters the input of each of the radiators. it is considered much more complicated: there, for each subsequent heating device, water is supplied with ever colder water. And if you want to calculate the number of radiators for a one-pipe system, you need to recalculate the temperature every time, and this is difficult and time-consuming. Which exit? One of the possibilities is to determine the power of the radiators as for a two-pipe system, and then add sections in proportion to the drop in thermal power to increase the heat transfer of the battery as a whole.

Let us explain with an example. The diagram shows a one-pipe heating system with six radiators. The number of batteries was determined for two-pipe wiring. Now you need to make an adjustment. For the first heater, everything remains the same. The second is supplied with a coolant with a lower temperature. Determine the% power drop and increase the number of sections by the corresponding value. The picture looks like this: 15kW-3kW = 12kW. We find the percentage: the temperature drop is 20%. Accordingly, to compensate, we increase the number of radiators: if 8 pieces were needed, it will be 20% more - 9 or 10 pieces. This is where knowledge of the room comes in handy: if it is a bedroom or a nursery, round it up, if a living room or other similar room, round it down. Take into account the location relative to the cardinal points: in the north you round it up, in the south you round it down.

This method is clearly not ideal: after all, it turns out that the last battery in the branch will have to have simply huge dimensions: judging by the scheme, a coolant with a specific heat equal to its power is supplied to its input, and it is impossible to remove 100% in practice. Therefore, usually when determining the power of the boiler for one-pipe systems, they take a certain margin, put shut-off valves and connect the radiators through the bypass so that the heat transfer can be adjusted, and thus compensate for the drop in the temperature of the coolant. One thing follows from all this: the number and / or size of radiators in a one-pipe system must be increased, and more and more sections must be installed as the distance from the beginning of the branch increases.

Outcomes

An approximate calculation of the number of heating radiator sections is a simple and quick business. But clarification, depending on all the features of the premises, size, type of connection and location, requires attention and time. But you can definitely decide on the number of heating devices to create a comfortable atmosphere in winter.

There are several different ways to determine the required power of heating devices. The calculation of heating radiators in an apartment can be carried out according to complex methods, which are associated with the use of rather complex equipment (thermal imagers) and specialized software.

The calculation of the number of heating radiators can be done independently, based on the required power of heating devices when calculating per unit area of ​​the room that is heated.

Conditionally schematic calculation of power

In the zone of the temperate climate (the so-called middle climatic zone), the adopted norms regulate the installation of heating radiators with a capacity of 60 - 100 W for each square meter of the room. This calculation is also called area calculation.

In the northern latitudes (meaning not the Far North, but the northern regions, which lie above 60 ° N), the power is taken in the range of 150-200 W per square meter.

The power of the heating boiler is also determined based on these values.

• The calculation of the power of heating radiators is carried out precisely according to this method. It is this power that heating radiators should have. The heat transfer values ​​of cast iron batteries are in the range of 125 - 150 W per section. In other words, a fifteen square meter room can be heated (15 x 100/125 = 12) with two six-piece cast iron radiators;
• Bimetallic radiators are calculated in a similar way, since their power corresponds to the power (in fact, it is slightly more). The manufacturer must indicate these parameters on the factory packaging (as a last resort, these values ​​are given in standard tables for specifications);
• Calculation of aluminum radiators is carried out in the same way. The temperature of the heaters themselves is to a large extent related to the temperature of the coolant inside the system and the heat transfer values ​​of each individual radiator. The overall price of the device is related to this.

There are simple algorithms that are called a general term: a calculator for calculating heating radiators, which uses the above techniques. Do-it-yourself calculation using such algorithms is quite simple.

Additional factors

The above values ​​of the radiator power are given for standard conditions, which are corrected using correction factors depending on the presence or absence of additional factors:

• The height of the room is considered standard if it is 2.7 m. For ceiling heights greater or less than this conventional standard power value, 100 W / m2 is multiplied by a correction factor, which is determined by dividing the height of the room by the standard (2.7 m).

For example, the coefficient for a room with a height of 3.24 m will be: 3.24 / 2.70 = 1.2, and for a room with 2.43 - 0.8 ceilings.

• The number of two outer walls in the room (corner room);
• The number of additional windows in the room;
• The presence of two-chamber energy-saving double-glazed windows.

Important!
It is better to calculate heating radiators using this method with some margin, since such calculations are rather approximate.

Calculation of heat loss

The above calculation of the heat output of heating radiators does not take into account many defining conditions. To be more precise, it is necessary to first determine the values ​​of the heat loss of the building. They are calculated on the basis of data on each wall and ceiling of each room, floor, type of windows and their number, door construction, plaster material, type of brick or insulation material.

Calculation of heat transfer from radiator heating batteries based on an indicator of 1 kW per 10 m2 has significant drawbacks, which are primarily associated with the inaccuracy of these indicators, since they do not take into account the type of the building itself (a detached building or apartment), ceiling height, dimensions of windows and doors ...

The formula for calculating heat loss:

TP total = V x 0.04 + TP o x n o + TP d x n d, where

• TP total - general heat loss in the room;
• V is the volume of the room;
• 0.04 - standard value of heat loss for 1 m3;
• TP o - heat loss from one window (taken as 0.1 kW);
• n o - number of windows;
• TP d - heat loss from one door (taken as 0.2 kW)
• n d is the number of doors.

Calculation of steel radiators

Pst = TPtotal / 1.5 x k, where

• Рst - power of steel radiators;
• TPtot - the value of the total heat loss in the room;
• 1.5 - coefficient for reducing the length of the radiator, taking into account the operation in the temperature range of 70-50 ° C;
• k - safety factor (1.2 - for apartments in a multi-storey building, 1.3 - for a private house)

An example of calculating a steel radiator

We proceed from the conditions that the calculation is performed for a room in a private house with an area of ​​20 square meters with a ceiling height of 3.0 m, which has two windows and one door.

The calculation instructions prescribe the following:

• TPtot = 20 x 3 x 0.04 + 0.1 x 2 + 0.2 x 1 = 2.8 kW;
• Pst = 2.8 kW / 1.5 x 1.3 = 2.43 m.

The calculation of steel heating radiators according to this method leads to the result that the total length of the radiators is 2.43 m. Taking into account the presence of two windows in the room, it would be advisable to choose two radiators of a suitable standard length.

Diagram of connection and placement of radiators

Heat transfer from radiators also depends on where the heater is located, as well as the type of connection to the main pipeline.

First of all, heating radiators are placed under windows. Even the use of energy-saving double-glazed windows does not make it possible to avoid the greatest heat loss precisely through the skylights. The radiator, which is installed under the window, heats the air in the room around it.

The heated air rises to the top. In this case, a layer of warm air creates a thermal curtain in front of the opening, which prevents the movement of cold layers of air from the window.

In addition, cold air currents from the window, mixing with warm upward currents from the radiator, enhance the overall convection throughout the entire volume of the room. This allows the air in the room to warm up faster.

In order for such a thermal curtain to be effectively created, it is necessary to install a radiator, which would be at least 70% of the width of the window opening in length.

The deviation of the vertical axes of radiators and windows should not exceed 50 mm.

Important!
In corner rooms, additional radiator panels should be placed along the outer walls, closer to the outer corner.

• When piping radiators, in which risers are used, they must be carried out in the corners of the room (especially in the outer corners of blank walls);
• When to the main pipelines from opposite sides, the heat transfer of the devices increases. From a constructive point of view, one-sided connection to pipes is rational.

Important!
Radiators in which the number of sections is more than twenty should be connected from different sides. This is also true for such a strapping when there is more than one radiator on one hitch.

Heat transfer also depends on how the places for supplying and removing heat carrier from heating devices are located. More heat flux will be when connecting the supply to the upper part and the outlet from the lower part of the radiator.

If the radiators are installed in several tiers, then in this case it is necessary to ensure the consistent movement of the coolant down in the direction of movement.

Video about calculating the power of heating devices:

Approximate calculation of bimetallic radiators

Almost all bimetallic radiators come in standard sizes. Non-standard must be ordered separately.

This somewhat facilitates the calculation of bimetallic heating radiators.

• With a standard ceiling height (2.5 - 2.7 m), one section of a bimetallic radiator is taken per 1.8 m2 of a living room.

For example, for a room of 15 m2, the radiator should have 8 - 9 sections:

• For the volumetric calculation of a bimetallic radiator, a value of 200 W of each section is taken for every 5 m3 of the room.

For example, for a room of 15 m2 and a height of 2.7 m, the number of sections according to this calculation will be 8:

15 x 2.7 / 5 = 8.1

Important!
200W standard wattage has been taken as standard by default. Although in practice there are sections of different power from 120 W to 220 W.

Determination of heat loss using a thermal imager

Thermal imagers are now widely used for careful monitoring of the thermal characteristics of objects and the determination of the thermal insulation properties of structures. With the help of a thermal imager, a quick survey of buildings is carried out in order to determine the exact value of heat loss, as well as hidden construction defects and poor quality materials.

The use of these devices makes it possible to determine the exact values ​​of real heat losses through structural elements. Taking into account the given coefficient of heat transfer resistance, these values ​​are compared with the standards. In the same way, the places of moisture condensation and irrational piping of radiators in the heating system are determined.