How many radiator sections are needed? SNP calculation of the number of heating radiator sections by room volume

Watts and sections

To calculate the number of sections of heating radiators, you need to know two values:

The amount of heat that is lost through the building envelope and which we need to compensate for;
Heat flow from one section.

Dividing the first value by three, we get the required number of sections.

About power

In calculations for batteries different types It is customary to operate with the following values of thermal power per section:

Cast iron radiator— 160 watts;

Bimetallic - 180 watts;

Aluminum - 200 watts.

As always, the devil is in the details.

Except standard size radiators (500 mm along the axes of the collectors), there are also low batteries designed for installation under window sills of non-standard height and creating a thermal curtain in front of panoramic windows. With an interaxial distance along the collectors of 350 mm, the heat flux per section decreases by 1.5 times (say, for an aluminum radiator - 130 watts), at 200 mm - by 2 times (for aluminum - 90-100 watts).

In addition, the actual heat transfer is greatly influenced by:

Coolant temperature (read: surface temperature of the heating device);
Room temperature.

Manufacturers usually specify the heat flux for the difference between these temperatures as 70 degrees (say 90/20C). However, the actual parameters of the heating system are often far from the maximum permissible 90-95C: in the central heating system, the supply temperature reaches 90C only at the peak of frost, and in an autonomous circuit the typical coolant temperature is 70C in the supply and 50C in the return pipeline.

Reducing the temperature delta by half (for example, from 90/20 to 60/25 degrees) will reduce the power of the section by exactly half. An aluminum radiator will deliver no more than 100 watts of heat per section, while a cast iron radiator will deliver no more than 80 watts.

Calculation schemes

Method 1: by area

The simplest calculation scheme takes into account only the area of the room. According to the standards of half a century ago, for one square meter The room should have 100 watts of heat.

Knowing the thermal power of the section, it is easy to find out how many radiators are needed per 1 m2. With a power of 200 watts per section, it is capable of heating 2 m2 of area; 1 square of the room corresponds to half the section.

As an example, let's calculate the heating of a room measuring 4x5 meters for cast iron radiators MS-140 (rated power 140 watts per section) at a coolant temperature of 70C and a room temperature of 22C.

The temperature delta between the media is 70-22=48C;
The ratio of this delta to the standard one, for which the stated power is 140 watts, is 48/70 = 0.686. This means that the real power under the given conditions will be equal to 140x0.686=96 watts per section;
The area of the room is 4x5=20 m2. Estimated heat demand - 20x100=2000 W;
The total number of sections is 2000/96=21 (rounded to the nearest whole value).

This scheme is extremely simple (especially if you use the nominal value of the heat flow), but it does not take into account a number of additional factors that influence the heat demand of the room.

Here is a partial list of them:

Rooms may vary in ceiling height. The higher the overlap, the larger the volume to be heated;

Increasing the ceiling height increases the temperature spread at the level and below the ceiling. In order to get the coveted +20 on the floor, it is enough to warm up the air under a 2.5-meter-high ceiling to +25C, and in a room 4 meters high the ceiling will be all +30. An increase in temperature increases the loss of thermal energy through the ceiling.

Through windows and doors in general case more heat is lost than through solid walls;

The rule is not universal. For example, triple glazing with two energy-saving glasses the thermal conductivity corresponds to 70 cm brick wall. A double-glazed unit with one i-glass transmits 20% more heat, while its price is 70% lower.

Location of the apartment in apartment building also affects heat loss. Corner and end rooms with walls common to the street will be clearly colder than those located in the center of the building;

Finally, heat loss is greatly affected by the climate zone. In Yalta and Yakutsk (average January temperatures are +4 and -39, respectively), the number of radiator sections per 1 m2 will predictably differ.

Method 2: by volume for standard insulation

Here are instructions for buildings that meet the requirements of SNiP 23-02-2003, which standardizes thermal protection buildings:

We calculate the volume of the room;
We take 40 watts of heat per cubic meter;
For corner and end rooms multiply the result by a factor of 1.2;
For each window we add 100 W to the result, for each door leading to the street - 200;

We multiply the resulting value by the regional coefficient. It can be taken from the table below.

Average January temperature	Coefficient
0	0,7
-10	1
-20	1,3
-30	1,6
-40	2

Let's find out how much heat is needed for our room measuring 4x5 meters by specifying a number of conditions:

The ceiling height in it is 3 meters;
The room is corner, with two windows;
It is located in the city of Komsomolsk-on-Amur (average January temperature is -25C).

Let's get started.

Room volume - 4x5x3=60 m3;
The basic value of heat demand is 60x40=2400 W;
Since the room is corner, we multiply the result by 1.2. 2400x1.2=2880;
Two windows add another 200 watts. 2880+200=3080;
Taking into account the climate zone, we use a regional coefficient of 1.5. 3080x1.5=4620 watts, which corresponds to 23 sections of aluminum radiators operating at rated power.

Now we will be curious and calculate how many radiator sections are needed per 1 m2. 23/20=1.15. Obviously, the calculation of the heat load according to the old SNiP (100 watts per square, or section per 2 m2) will be too optimistic for our conditions.

Method 3: by volume for non-standard insulation

How to calculate the number of batteries per room in a building that does not meet the requirements of SNiP 23-02-2003 (for example, in panel house Soviet-built or in a modern “passive” house with extremely effective insulation)?

Heat demand is estimated using the formula Q=V*Dt*k/860, where:

Q is the desired value in kilowatts;
V—heated volume;
Dt—temperature difference between indoors and outdoors;
k is a coefficient determined by the quality of insulation.

The temperature difference is calculated between sanitary standard for a living space (18-22C depending on the climate zone and the location of the room inside the building) and the temperature of the coldest five-day period of the year.

The insulation coefficient can be taken from another table:

As an example, we will again analyze our room in Komsomolsk-on-Amur, once again clarifying the input data:

The coldest five-day temperature for this climate zone is -31C;

The absolute minimum is lower and is -44C. However, extreme cold does not last long and is not included in the calculations.

The walls of the house are brick, half a meter thick (two bricks). The windows are triple glazed.

So:

We have already calculated the volume of the room earlier. It is equal to 60 m3;
Sanitary standard for corner room and a region with a minimum of winter temperatures below -31C - +22, which in combination with the temperature of the coldest five-day period gives us Dt = (22 - -31) = 53;
Let's take the insulation coefficient equal to 1.2;

The heat requirement will be 60x53x1.2/860=4.43 kW, or 22 sections of 200 watts each. The result is approximately equal to that obtained in the previous calculation due to the fact that the insulation of the house and windows meets the requirements of SNiP, which regulates the thermal protection of buildings.

Useful little things

The actual heat transfer of heating radiators is influenced by a number of additional factors, which should also be taken into account in the calculations:

With unilateral lateral connection The power of all sections corresponds to the nominal only if their number is no more than 7-10. The far edge of a longer battery will be much colder than the liners;

The problem is being solved diagonal connection. In this case, all sections will be heated evenly, regardless of their number.

In most newly built houses, the heating supply and return bottlings are located in the basement, which means that the risers are connected in pairs by jumpers on the upper floor. The radiator on the return riser will always be colder than the radiator on the supply;
Various screens and niches again reduce the heat transfer of the heating system, and the difference with the rated thermal power can reach 50%;

The throttling fittings on the inlet limit the flow of water through the radiator even when fully open. The drop in thermal power is determined by the inductor configuration and is usually 10-15%. An exception is full bore ball and plug valves;

Radiators with one-way side connections in the central heating system gradually become silted. As silting occurs, the temperature of the outer sections will drop.

To combat dirt, the battery is periodically washed through a flushing valve installed in the lower manifold of the outer section. The hose connected to it is directed into the sewer, after which a certain amount of coolant is discharged through it.

Conclusion

As you can see, simple circuits Heating calculations do not always give accurate results. The video in this article will help you learn more about calculation methods. Feel free to share your own experience in the comments. Good luck, comrades!

At the stage of preparation for capital repair work and in the process of planning the construction of a new house, the need arises to calculate the number of heating radiator sections. The results of such calculations make it possible to find out the number of batteries that would be enough to provide an apartment or house with sufficient heat even in the coldest weather.

The calculation procedure may vary depending on many factors. Check out the instructions for a quick calculation for typical situations, for non-standard rooms, as well as the procedure for performing the most detailed and accurate calculations, taking into account all possible significant characteristics premises.

Heat transfer indicators, the shape of the battery and the material of its manufacture - these indicators are not taken into account in the calculations.

Important! Do not perform calculations for the entire house or apartment at once. Take a little more time and do the calculations for each room separately. This is the only way to obtain the most reliable information. At the same time, in the process of calculating the number of battery sections for heating a corner room, you need to add 20% to the final result. The same reserve must be added on top if there are interruptions in the heating operation or if its efficiency is not enough for high-quality heating.

Let's start the training by considering the most commonly used calculation method. It can hardly be considered the most accurate, but in terms of ease of implementation it definitely takes the lead.

According to this “universal” method, 100 W of battery is needed to heat 1 m2 of room area. IN in this case calculations are limited to one simple formula:

K =S/U*100

In this formula:

As an example, let's look at the procedure for calculating the required number of batteries for a room with dimensions of 4x3.5 m. The area of such a room is 14 m2. The manufacturer claims that each section of the battery it produces produces 160 W of power.

We substitute the values into the above formula and find that to heat our room we need 8.75 radiator sections. We round up, of course, i.e. to 9. If the room is corner, add a 20% margin, round up again, and get 11 sections. If at work heating system problems are observed, add another 20% to the originally calculated value. It will turn out to be about 2. That is, in total for heating a 14-meter corner room in conditions unstable work The heating system will require 13 battery sections.

Approximate calculation for standard premises

A very simple calculation option. It is based on the fact that the size of mass-produced heating batteries is practically the same. If the room height is 250 cm (standard for most living spaces), then one radiator section can heat 1.8 m2 of space.

The area of the room is 14 m2. To calculate, it is enough to divide the area value by the previously mentioned 1.8 m2. The result is 7.8. Round up to 8.

Thus, to warm up a 14-meter room with a 2.5-meter ceiling, you need to buy a battery with 8 sections.

Important! Do not use this method when calculating a low-power unit (up to 60 W). The error will be too large.

Calculation for non-standard rooms

This calculation option is suitable for non-standard rooms with too low or too low high ceilings. The calculation is based on the statement that to warm up 1 m3 of living space you need about 41 W of battery power. That is, calculations are performed using a single formula that looks like this:

A=Bx41,

A – the required number of sections of the heating battery;
B is the volume of the room. It is calculated as the product of the length of the room by its width and height.

For example, consider a room 4 m long, 3.5 m wide and 3 m high. Its volume will be 42 m3.

We calculate the total thermal energy requirement of this room by multiplying its volume by the previously mentioned 41 W. The result is 1722 W. For example, let's take a battery, each section of which produces 160 W of thermal power. We calculate the required number of sections by dividing the total need for thermal power by the power value of each section. The result will be 10.8. As usual, we round to the nearest larger integer, i.e. until 11.

Important! If you bought batteries that are not divided into sections, divide the total heat requirement by the power of the whole battery (indicated in the accompanying technical documentation). That's how you'll know required quantity heating

Calculation required quantity radiators for heating

The most accurate calculation option

From the above calculations, we saw that none of them is perfectly accurate, because... Even for identical rooms, the results, albeit slightly, are still different.

If you need maximum calculation accuracy, use the following method. It takes into account many coefficients that can affect heating efficiency and other significant indicators.

In general, the calculation formula is as follows:

T =100 W/m 2 * A * B * C * D * E * F * G * S ,

where T is the total amount of heat required to heat the room in question;
S – area of the heated room.

The remaining coefficients require more detailed study. So, coefficient A takes into account the characteristics of the glazing of the room.

The values are as follows:

1.27 for rooms whose windows are glazed with just two glasses;
1.0 – for rooms with windows equipped with double glazing;
0.85 – if the windows have triple glazing.

Coefficient B takes into account the features of insulation of room walls.

The dependency is as follows:

if the insulation is low-effective, the coefficient is taken equal to 1.27;
at good insulation(for example, if the walls are laid with 2 bricks or are purposefully insulated with a high-quality heat insulator), a coefficient of 1.0 is used;
at high level insulation – 0.85.

Coefficient C indicates the ratio of the total area window openings and floor surfaces in the room.

The dependency looks like this:

with a ratio of 50%, coefficient C is taken as 1.2;
if the ratio is 40%, use a coefficient equal to 1.1;
with a ratio of 30%, the coefficient value is reduced to 1.0;
in the case of an even smaller percentage, coefficients equal to 0.9 (for 20%) and 0.8 (for 10%) are used.

Coefficient D indicates the average temperature during the coldest period of the year.

The dependency looks like this:

if the temperature is -35 and below, the coefficient is taken equal to 1.5;
at temperatures up to -25 degrees, a value of 1.3 is used;
if the temperature does not drop below -20 degrees, the calculation is carried out with a coefficient of 1.1;
residents of regions where the temperature does not drop below -15 should use a coefficient of 0.9;
if the temperature in winter does not fall below -10, count with a coefficient of 0.7.

The E coefficient indicates the amount external walls.

If there is only one external wall, use a factor of 1.1. With two walls, increase it to 1.2; with three – up to 1.3; if there are 4 external walls, use a coefficient of 1.4.

Coefficient F takes into account the characteristics of the room above. The dependency is:

if there is an unheated area above attic space, the coefficient is taken equal to 1.0;
if the attic is heated - 0.9;
if the neighbor above is a heated living room, the coefficient can be reduced to 0.8.

And the last coefficient of the formula is G – takes into account the height of the room.

The order is as follows:

in rooms with ceilings 2.5 m high, the calculation is carried out using a coefficient of 1.0;
if the room has a 3-meter ceiling, the coefficient is increased to 1.05;
with a ceiling height of 3.5 m, count with a coefficient of 1.1;
rooms with a 4-meter ceiling are calculated with a coefficient of 1.15;
when calculating the number of battery sections for heating a room 4.5 m high, increase the coefficient to 1.2.

This calculation takes into account almost all existing nuances and allows you to determine required number sections of the heating unit with the smallest error. In conclusion, all you have to do is divide the calculated figure by the heat transfer of one section of the battery (check in the attached data sheet) and, of course, round the found number up to the nearest integer value.

Before the beginning heating season the problem of good and quality heating dwellings. Especially if repairs are being made and batteries are changed. The range of heating equipment is quite rich. Batteries are offered in different capacities and types. Therefore, it is necessary to know the features of each type in order to correctly select the number of sections and type of radiator.

What are heating radiators and which one should you choose?

A radiator is a heating device consisting of separate sections that are connected to each other by pipes. Coolant circulates through them, which most often is plain water, heated to required temperature. Radiators are primarily used for heating residential premises. There are several types of radiators, and it is difficult to decide which is best or worst. Each type has its own advantages, which are mainly represented by the material from which the heating device is made.

Cast iron radiators. Despite some criticism of them and unfounded claims that cast iron has weaker thermal conductivity than other varieties, this is not entirely true. Modern cast iron radiators have high thermal power and are compact. In addition, they have other advantages:
- Large mass is a disadvantage during transportation and delivery, but weight leads to greater heat capacity and thermal inertia.
- If the house experiences changes in the temperature of the coolant in the heating system, cast iron radiators better maintain the heat level due to inertia.
- Cast iron is poorly susceptible to the quality and level of water clogging and overheating.
- Durability cast iron batteries surpasses all analogues. In some houses, old batteries from Soviet times are still visible.

Among the disadvantages of cast iron, it is important to know about the following:

heavy weight provides a certain inconvenience during maintenance and installation of batteries, and also requires reliable mounting fasteners,
cast iron periodically needs painting,
since the internal channels have a rough structure, plaque appears on them over time, which leads to a decrease in heat transfer,
cast iron requires a higher temperature for heating and in case of weak supply or insufficient temperature of heated water, the radiators heat the room worse.

Another disadvantage that is worth highlighting separately is the tendency for the gaskets between sections to collapse. According to experts, this manifests itself only after 40 years of operation, which in turn once again emphasizes one of the advantages of cast iron radiators - their durability.

Aluminum batteries are considered optimal choice, since they have high thermal conductivity in combination with a larger surface area of the radiator due to protrusions and fins. Their advantages include the following:
- light weight,
- ease of installation,
- high working pressure,
- small radiator dimensions,
- high degree of heat transfer.

The disadvantages of aluminum radiators include their sensitivity to clogging and corrosion of metal in water, especially if the battery is exposed to small stray currents. This is fraught with an increase in pressure, which can lead to rupture of the heating battery.

To eliminate the risk, the inside of the battery is coated with a polymer layer that can protect the aluminum from direct contact with water. In the same case, if the battery does not have an inner layer, it is highly not recommended to turn off the water taps in the pipes, as this may cause a rupture of the structure.

A good choice would be to buy bimetallic radiator, consisting of aluminum and steel alloys. Such models have all the advantages of aluminum, while the disadvantages and danger of rupture are eliminated. It should be taken into account that their price is correspondingly higher.
Steel radiators are available in different form factors, which allows you to choose a device of any power. They have the following disadvantages:
- low operating pressure, usually up to 7 atm,
- the maximum coolant temperature should not exceed 100°C,
- lack of corrosion protection,
- weak thermal inertia,
- sensitivity to changes in operating temperatures and hydraulic shocks.

Steel radiators are characterized large area heating surface, which stimulates the movement of heated air. It is more appropriate to classify this type of radiator as a convector. Since a steel heater has more disadvantages than advantages, if you want to buy a radiator of this type, you should first pay attention to bimetallic structures or cast iron batteries.

The last variety is oil radiators. Unlike other models, oil models are devices independent from the general central heating system and are often purchased as an additional mobile heating device. As a rule, it reaches maximum heating power within 30 minutes after heating, and in general, represents a very useful device, especially relevant in country houses.

When choosing a radiator, it is important to pay attention to their service life and operating conditions. There is no need to save and buy cheap models of aluminum radiators without polymer coating because they are highly susceptible to corrosion. In fact, the most preferable option is still a cast iron radiator. Sellers try to force the purchase of aluminum structures, emphasizing that cast iron is outdated - but this is not the case. If we compare numerous reviews by type of battery, cast iron heating batteries still remain the best investment. This does not mean that you should stick to the old ribbed MC-140 models from the Soviet era. Today, the market offers a significant range of compact cast iron radiators. The starting price of one section of a cast iron battery starts from $7. For lovers of aesthetics, radiators that represent entire artistic compositions are available for sale, but their price is much higher.

Necessary values for calculating the number of heating radiators

Before you begin the calculation, you need to know the basic coefficients that are used to determine the required power.

Glazing: (k1)

triple energy-saving double glazing = 0.85
double energy saving = 1.0
simple double glazing = 1.3

Thermal insulation: (k2)

concrete slab with a layer of polystyrene foam 10 cm thick = 0.85
brick wall two bricks thick = 1.0
regular concrete panel - 1,3

Ratio to window area: (k3)

10% = 0,8
20% = 0,9
30% = 1,0
40% = 1.1, etc.

Minimum temperature outside the room: (k4)

- 10°C = 0.7
- 15°C = 0.9
- 20°C = 1.1
- 25°C = 1.3

Room ceiling height: (k5)

2.5 m, which represents standard apartment = 1,0
3 m = 1.05
3.5m = 1.1
4 m = 1.15

Heated room coefficient = 0.8 (k6)

Number of walls: (k7)

one wall = 1.1
corner apartment with two walls = 1.2
three walls = 1.3
detached house with four walls = 1.4

Now, to determine the power of the radiators, you need to multiply the power indicator by the area of the room and by the coefficients using this formula: 100 W/m2*Sroom*k1*k2*k3*k4*k5*k6*k7

There are many calculation methods, from which you should choose the most convenient one. We will talk about them further.

How many heating radiators do you need?

The first method is standard and allows you to calculate by area. For example, according to building regulations, heating one square meter of area requires 100 watts of power. If the room has an area of 20 m², and the average power of one section is 170 Watts, then the calculation will look like this:

20*100/170 = 11,76

The resulting value must be rounded up, so to heat one room you will need a battery with 12 radiator sections with a power of 170 watts.

An approximate calculation method will make it possible to determine the required number of sections based on the area of the room and the height of the ceilings. In this case, if we take as a basis the heating rate of one section of 1.8 m² and the ceiling height of 2.5 m, then with the same room size the calculation 20/1,8 = 11,11 . Rounding this figure up, we get 12 battery sections. It should be noted that this method has a larger error, so it is not always advisable to use it.
the third method is based on calculating the volume of the room. For example, a room is 5 m long, 3.5 m wide, and the ceiling height is 2.5 m. Taking as a basis the fact that heating 5 m3 requires one section with a thermal power of 200 Watts, we get the following formula:

(5*3,5*2,5)/5 = 8,75

We round up again and find that to heat a room you need 9 sections of 200 Watt each, or 11 sections of 170 Watt each.

It is important to remember that these methods have errors, so it is better to set the number of battery sections to one more. Besides, building codes assume minimum room temperature indicators. If it is necessary to create a hot microclimate, then it is recommended to add at least five more sections to the resulting number of sections.

Calculation of required power for radiators

The volume of the room is determined. For example, an area of 20 m and a ceiling height of 2.5 m:

After increasing the indicator upward, the required radiator power value is 2100 Watts. For cold winter conditions with air temperatures below -20°C, it makes sense to additionally take into account a power reserve of 20%. In this case, the required power will be 2460 watts. Equipment of such thermal power should be looked for in stores.

You can correctly calculate heating radiators using the second calculation example, based on taking into account the area of the room and the coefficient for the number of walls. For example, we take one room with an area of 20 m² and one outer wall. In this case, the calculations look like this:

20*100*1.1 = 2200 Watt, where 100 is standard thermal power. If we take the power of one radiator section at 170 Watts, we get a value of 12.94 - that is, we need 13 sections of 170 Watts each.

It is important to pay attention to the fact that overestimation of heat transfer becomes a frequent phenomenon, therefore, before purchasing a heating radiator, you need to study the technical data sheet to find out the minimum heat transfer value.

As a rule, there is no need to calculate the radiator area; the required power or thermal resistance, and then suitable model choose from the assortment offered by sellers. In the event that an accurate calculation is required, it is better to turn to specialists, since you will need knowledge of the parameters of the composition of the walls and their thickness, the ratio of the area of the walls, windows and the climatic conditions of the area.

Cast iron radiators are valued for their reliability, unpretentiousness, simplicity of design.

They have high stability to corrosion and indispensable in open systems with a high oxygen content in water.

Thermal inertia of cast iron heating devices ensures stability temperature regime indoors with sharp fluctuations in coolant parameters in centralized systems heating.

When calculating the required number of sections, use two ways -simplified and accurate.

A simplified method for calculating the number of sections of cast iron batteries

Exists several formulas to calculate the number of heating radiators.

Per square meter of area, table

The technique is based on the statement that for heating 1 m² living area of the room in middle lane Russia needs 100 W thermal power of the heating device.

Photo 1. Option for calculating the number of cast iron radiators per square meter of area in a residential area.

Number of radiator sections calculated by formula (1):

N = (100 X S)/Q (1)

N
S— room area, m²;
Q- heat transfer one section, Tue.

At non-standard coolant temperatures

The thermal power of one radiator section is indicated in the passport for standard values inlet temperature Tpod = 90ºС and device output Tobr = 70ºС.

If in the heating system of a private house the coolant temperature has different values, then the heat transfer of the section Q calculated by formula (2):

Q = K X ∆ T(2)

K— reduced coefficient depending on physical characteristics radiator sections;
∆ T— temperature difference, calculated by formula (3):

∆ T= 0,5 X ( Tpod + Tobr) — Tpom(3)

Tpod— temperature at the inlet of the heating device;
Tobr— outlet temperature;
Tpom- required room temperature ( 20ºС).

Calculation of value Q at given coolant temperatures at the inlet and outlet of the heating device, it is performed in the following sequence:

The value of the reduced coefficient is calculated TO from formulas (2), (3) for known nameplate quantities Q at standard Tpod = 90ºС, Tobr = 70ºС.
The difference is determined ∆ T according to formula (3) for real parameters Tpod And Tobr.
Calculated Q according to formula (2).

Photo 2. Cast iron radiator installed in a living room. The device is decorated with decorative forging.

For non-standard ceiling heights

Formula 1) valid for standard height rooms - from 2.5 to 3 m. For other room heights, use formula (4):

N = (H X Y X S)/Q (4)

N— number of sections (rounded to the nearest whole number);
H— room height, m;
Y— specific power equal to 41 W/m³ For panel houses made of reinforced concrete or 34 W/m³ for brick buildings or private houses with external insulation;
S— room area, m²;
Q— heat transfer of one section, W.

How to accurately calculate the number of heating radiators?

As a basis techniques formula (1) is taken with coefficients that take into account the climatic features of the area and the parameters of the building structures, on which the heat loss in the calculated room depends.

Number of radiator sections N with an exact calculation it is determined by formula (5):

N = K1 X K2 X K3 X K4 X K5 X K6 X K7 X K8 X K9 X K10 X ( 100 X S)/Q (5)

N— number of sections (rounded to the nearest whole number);
S— room area, m²;
Q-thermal power one section, Tue.
K1…K10 correction factors.

K1 - by the number of external walls in the room

Coefficient K1 equal to:

0,8 - indoor premises;
1,0 - room with one outer wall;
1,2 - corner room - two partitions with the street;
1,4 - three walls to the street.

K2 - for orientation to the cardinal points

The degree of heating depends on the location of the external partitions in the room. sun rays. Coefficient K2 equal to:

1,1 - external walls are oriented east or north;
1,0 - the walls of the room “look” to the west or south.

K3 - on the degree of wall insulation

It depends on the characteristics of the insulation thermal resistance walls, affecting the heat loss of the room. Coefficient K3 equal to:

1,27 - outer wall not insulated;
1,0 - room partitions made of two bricks without insulation;
0,85 - a wall with insulation, the calculated value of the thermal resistance of the entire wall complies with SNiP standards.

Checking compliance with SNiP standards of the thermal resistance of the wall, as multilayer construction, is performed in the following sequence:

Each layer has its own thermal resistance calculated R i by formula (6):

R i = h / λ (6)

h- layer thickness, m;
λ - thermal conductivity coefficient of one layer.

The obtained resistance values of all layers are summed up.
The calculated amount is compared with the normalized value for the given area.

K4 - on the peculiarities of the climatic conditions of the region

This coefficient depends on the climate zone in which the house is located. Depending on the average temperature Tav for the five coldest winter days coefficient K4 equal to:

1,5 : Тср ≤ -35°C;
1.3: -30 °C≥Tsr > -35 °C;
1.2: -25°C≥ Тср > -30 °C;
1.1: -20°C≥ Тср > -25 °C;
1.0: -15°C≥Tsr > -20 °C;
0.9: -10°C≤Tsr > -15 °C;
0,7: Tsr > -10°C.

K5 - ceiling height coefficient

Depending on height N ceilings of the room coefficient value K5 is equal to:

1,0: H < 2.7 m;
1.05:2.7m ≤ H < 3.0 m;
1.1: 3.0m ≤ H < 3.5 m;
1.15: 3.5m ≤ H < 4.0 m;
1,2: H ≥ 4.0 m.

K6 - for the type of room located above

Coefficient value K6 is equal to:

1,0 - on top of the room there is an uninsulated attic or roof;
0,9 - above the room there is an insulated attic;
0,8 - the upper room is heated.

K7 - on the types of installed windows

Depending on the type of glazing, the coefficient K7 equal to:

1,27 - wooden windows with double glazing;
1,0 - plastic or wooden windows modern design with single-chamber double-glazed windows;
0,85 - double-glazed windows, number of cameras more than one.

K8 - per glazing area

Calculation of coefficient K8:

Calculate the total area of all windows in the room.
Divide the resulting number by the area of the room to obtain the given value Spr.

Depending on the size Spr coefficient value K8 is equal to:

0,8: 0 0,1;
0,9: 0,11 0,2;
1,0: 0,21 0,3;
1,1: 0,31 0,4;
1,2: 0,41 0,5.

When designing heating systems, a mandatory step is to carry out power calculations heating devices. The result obtained largely influences the choice of one or another equipment - heating radiators and heating boilers (if the project is carried out for private houses not connected to central heating systems).

The most popular batteries at the moment are those made in the form of interconnected sections. In this article we will talk about how to calculate the number of radiator sections.

Methods for calculating the number of battery sections

In order to calculate the number of sections of heating radiators, you can use three main methods. The first two are quite easy, but they give only an approximate result, which is suitable for typical premises of multi-story buildings. This includes the calculation of radiator sections by room area or volume. Those. in this case, it is enough to find out the required parameter (area or volume) of the room and insert it into the appropriate formula for calculation.

The third method involves the use of many different coefficients for calculations that determine the heat loss of the room. This includes the size and type of windows, floor, type of wall insulation, ceiling height and other criteria that affect heat loss. Heat loss can also occur for various reasons related to errors and shortcomings during the construction of a house. For example, there is a cavity inside the walls, the insulation layer has cracks, there is a defect in building material etc. Thus, searching for all the causes of heat leakage is one of the mandatory conditions to perform an accurate calculation. For this purpose, thermal imagers are used, which display on the monitor the places of heat leakage from the room.

All this is done in order to select a radiator power that compensates for the total heat loss. Let's consider each method of calculating battery sections separately and give a clear example for each of them.

Calculation of the number of radiator sections by room area

This method is the simplest. To obtain the result, you will need to multiply the area of the room by the value of the radiator power required to heat 1 sq.m. This value is given in SNiP, and it is:

60-100W for the middle climatic zone of Russia (Moscow);
120-200W for areas located further north.

The calculation of radiator sections according to the average power parameter is carried out by multiplying it by the value of the room area. So, 20 sq.m. will require for heating: 20 * 60 (100) = 1200 (2000) W

Next, the resulting number must be divided by the power value of one radiator section. To find out how much area 1 radiator section is designed for, just open the equipment data sheet. Let's assume that the power of the section is 200 W, and the total power required for heating is 1600 W (let's take the arithmetic average). All that remains is to clarify how many radiator sections are needed per 1 m2. To do this, divide the value of the required power for heating by the power of one section: 1600/200 =8

Result: to heat a room of 20 square meters. m. you will need an 8-section radiator (provided that the power of one section is 200W).

Calculating sections of heating radiators based on the area of the room gives only an approximate result. In order not to make a mistake with the number of sections, it is best to make calculations on the condition that for heating 1 sq.m. 100W power required.

This, as a result, will increase the overall costs of installing the heating system, and therefore such a calculation is not always appropriate, especially with a limited budget. The following method will give a more accurate, but still the same approximate result.

The method of this calculation is similar to the previous one, except that now from SNiP you will need to find out the power value for heating not 1 sq.m., but a cubic meter of room. According to SNiP this is:

41W for heating premises of panel-type buildings; 34W for brick houses.

As an example, let's take the same room of 20 square meters. m., and set the conditional ceiling height to 2.9 m. In this case, the volume will be equal to: 20 * 2.9 = 58 cubic meters

From this: 58*41 =2378 W for a panel house 58*34 =1972 W for brick house

Let us divide the results obtained by the power value of one section. Total: 2378/200 =11.89 (panel house) 1972/200 =9.86 (brick house)

If you round up to a larger number, then to heat a room of 20 square meters. m. of a panel house you will need 12-section radiators, and for a brick house 10-section radiators. And this figure is also approximate. In order to calculate with high accuracy how many battery sections are needed for space heating, it is necessary to use more in a complicated way, which will be discussed below.

To carry out an accurate calculation in general formula special coefficients are introduced that can either increase (increase factor) the value of the minimum radiator power for heating the room or decrease it (reduction factor).

In fact, there are many factors influencing the power value, but we will use those that are easy to calculate and easy to operate with. The coefficient depends on the values following parameters premises:

Ceiling height:
- At a height of 2.5 m the coefficient is 1;
- At 3m – 1.05;
- At 3.5m – 1.1;
- At 4m – 1.15.
Type of glazing of indoor windows:
- Simple double glass - coefficient is 1.27;
- Double-glazed window - 1;
- Triple glazing – 0.87.
The percentage of window area from the total area of the room (for ease of determination, you can divide the window area by the area of the room and then multiply by 100):
- If the result of the calculation is 50%, a coefficient of 1.2 is taken;
- 40-50% – 1,1;
- 30-40% – 1;
- 20-30% – 0,9;
- 10-20% – 0,8.
Thermal insulation of walls:
- Low level thermal insulation - coefficient is 1.27;
- Good thermal insulation (two bricks or 15-20cm insulation) – 1.0;
- Increased thermal insulation (wall thickness from 50cm or insulation from 20cm) – 0.85.
Average value minimum temperature in winter, which can last a week:
- -35 degrees – 1.5;
- -25 – 1,3;
- -20 – 1,1;
- -15 – 0,9;
- -10 – 0,7.
Number of external (end) walls:
- 1 end wall – 1,1;
- 2 walls – 1.2;
- 3 walls – 1.3.
Type of room above the heated room:
- Unheated attic – 1;
- Heated attic – 0.9;
- Heated living space - 0.85.

From here it is clear that if the coefficient is above one, then it is considered increasing, if lower - decreasing. If its value is one, then it does not affect the result in any way. To make the calculation, you need to multiply each of the coefficients by the value of the room area and the average specific value heat losses per 1 sq.m., which is (according to SNiP) 100 W.

Thus, we have the formula: Q_T= γ*S*K_1*…*K_7,where

Q_T – required power of all radiators to heat the room;

average value

total area

Room area – 18 sq.m.;
Ceiling height – 3m;
Window with regular double glass;
The window area is 3 sq.m., i.e. 3/18*100 = 16.6%;
Thermal insulation – double brick;
The minimum outside temperature for a week straight is -20 degrees;
One end (external) wall;
The room above is a heated living room.

Now let's replace literal values into numbers and we get: Q_T= 100*18*1.05*1.27*0.8*1*1.3*1.1*0.85≈2334 W

It remains to divide the result by the power value of one radiator section. Let's assume that n is equal to 160W: 2334/160 =14.5

Those. for heating a room of 18 sq.m. and the given heat loss coefficients, you will need a radiator with 15 sections (rounded up).

There is another one easy way how to calculate radiator sections based on the material they are made of. In fact, this method does not give an exact result, but it helps to estimate the approximate number of battery sections that will need to be used in the room.

Heating batteries are usually divided into 3 types depending on the material they are made of. These are bimetallic, which use metal and plastic (usually as outer covering), cast iron and aluminum radiators heating. The calculation of the number of battery sections made of one material or another is the same in all cases. Here it is enough to use the average value of the power that one radiator section can produce and the value of the area that this section can warm up:

For aluminum batteries it is 180W and 1.8 sq. m;
Bimetallic – 185W and 2 sq.m.;
Cast iron - 145W and 1.5 sq.m.

Using a simple calculator, the number of heating radiator sections can be calculated by dividing the area of the room by the area that one radiator section made of the metal of interest can heat. Let's take a room of 18 square meters. m. Then we get:

18/1.8 = 10 sections (aluminum);
18/2 = 9 (bimetal);
18/1.5 = 12 (cast iron).

The area that one radiator section can heat is not always indicated. Manufacturers usually indicate its power. In this case, you will need to calculate the total power required to heat the room using any of the above methods. If we take the calculation by area and the power required to warm up 1 sq.m. in 80 W (according to SNiP), then we get: 20*80=1800/180 =10 sections (aluminum); 20*80=1800/185 =9.7 sections (bimetal); 20*80=1800/145 =12.4 sections (cast iron);

By rounding the decimal numbers to one side, we get approximately the same result, as in the case of calculations by area.

It is important to understand that calculating the number of sections based on the metal of a radiator is the most inaccurate method. It can help you decide on one battery or another, and nothing else.

And finally, a piece of advice. Almost every heating equipment manufacturer or online store places a special calculator on its website to calculate the number of heating radiator sections. It is enough to enter the required parameters into it, and the program will output the desired result. But, if you don’t trust the robot, then the calculations, as you can see, are quite easy to do yourself, even on a piece of paper.

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