What area is heated by one section of a cast-iron radiator. Calculation of the number of heating radiator sections
You have decided to replace the old radiators with new ones. The store has already made a choice of suitable size and design heater... The question arises before you, how many sections of heating radiators are needed for each room of your apartment or house.
A simple on-line calculator has been developed to calculate the power of heating radiators.
You only need to enter the area of the room for which the radiator is selected. You also need to select parameters that affect additional heat loss (number of windows and outer walls, type of glass unit, material of sections of the selected radiators).
Calculation method
"Building rules and regulations" recommend to maintain the required temperature in the room during the heating season to have 100 watts of heating device power per 1 m2 of area. Accordingly, the calculation can be performed using the formula:
I = S * 100 / P, where
I - required amount sections of heating radiators;
S is the area of the room (m2);
P - Thermal power of one section of the radiator (see product data sheet);
Also, the following factors are taken into account in the formula for calculating the power of radiators:
Window type (k1) - plastic double-glazed windows reduce heat loss;
The number of external walls (k2) - the more external walls, the greater the coefficient;
The type of room above the calculated room (k3) - a warm attic and a heated room reduce the number of sections, and cold attic increases;
Ceiling height (k4) - with a ceiling height of 2.5 m, the coefficient is 1. For more high ceiling k4 increases;
The k5 factor takes into account the number of windows.
The material from which heating radiators are made directly affects heat output section.
The calculation takes the average value for each type of radiator with center distance 500 mm: 
Cast iron radiators P = 145 W;
Bimetallic radiators P = 185 W;
Aluminum radiators P = 190 W.
The general formula is as follows:
I = S * k1 * k2 * k3 * k4 * k5 * 100 / P
This calculator for calculating the number of sections of heating batteries, for convenience, rounds the result to an integer for ease of use.
The easiest calculation of the number of radiators
Three-step instruction
To calculate the number of radiators in an apartment, we need 5 minutes To calculate the number of radiators in an apartment, we need 5 minutes
A salesman in the Plumbing and Heating store was stunned: "You need 26 ribs for a room." To that 
time I had 10 cast-iron ribs, and, although they did not heat enough, I understood that 26 ribs aluminum radiator for a room with an area of 18 square meters - this is too much. The seller was either mistaken or wanted me to be very, very warm. I did not check the seller's calculations, but rummaged through the reference literature and found a simple and effective technique calculating the number of radiators, regardless of what type they are: copper convectors, aluminum or metal panels.
The calculation will be carried out using an example:
There is a room with an area of 12 square meters 4 (m) * 3 (m) and a height of 2.7 meters (a standard room in a Soviet-built high-rise building):
The first thing you need to know to calculate is the volume of your room. We multiply the length and width by the height (in meters) (4 * 3 * 2.7) - and we get the number 32.4. This is the volume of the room in cubic meters.
Second: to heat one cubic meter in a standard building (without metal-plastic windows, foam insulation, etc., energy-saving measures) in the climatic conditions of Ukraine, Belarus, Moldova and the European part of Russia, including Moscow and Nizhny Novgorod, 41 W of thermal power is required ...
We find out how much heat we need, for this we multiply our (your) volume V by the number 41:
V * 41 = 32.4 * 41 W = 1328.4 W.
The resulting figure is the amount of heat that radiators must give in order to heat up your room. Let's round it up to 1300.
But how can you “scratch out” the number of radiators from this figure?
It's very simple: any radiator on the package or in the complete insert has information about the heat output. Thermal power is the amount of heat that a radiator can give off when cooled from a heating temperature to room temperature - 20 degrees Celsius. The power of the batteries and fins must be known to every seller of a specialized store, or it can be easily found on the Internet for the model you are interested in.
Manufacturers usually overestimate the thermal power of their products, I will tell you about the refined calculation in the next post. In the meantime, we are interested in the approximate number of radiators.
In our case, we can limit ourselves to steel panel radiator with a power of 1300 watts. However, what if suddenly the street gets VERY COLD?
For reliability, it is worth increasing the resulting figure by 20 percent. To do this, multiply 1300 by a factor of 1.2 - we get 1560. Radiators of such power are not sold, so we round the figure down - up to 1500 W or 1.5 kilowatts.
That's all, this is the figure that we need. A radiator of any type: bimetallic, aluminum, cast iron, steel, white speckled and black with stripes will provide us with heating the room in any frost possible in our latitudes, if it produces 1500 watts of heat.
For example, the typical strength of an aluminum or bimetal radiator about 60 centimeters high - 150 watts. Thus, we need 10 edges. Similarly - for standard cast-iron radiators of the MC-140 type
To find out the number of heating devices for the entire apartment, we carry out the calculation for each room separately.
If the apartment is "cold", with a lot of windows, thin walls, on the first one either top floor etc., 47 watts per cubic meter will be needed for heating, therefore, in the calculations we substitute this figure instead of 41.
If "warm", with metal-plastic windows, insulation of floors, walls, in a house built using modern insulation materials - we take 30 watts.
And finally, the easiest way to calculate:
If you had standard cast-iron radiators with a height of about 60 centimeters in your room before replacing, and you were warm with them, feel free to count their number and multiply by 150 W - you will find out the required power of the new ones. If you are planning to choose aluminum or bimetal ribs, you can buy them counting - for one “cast iron” rib - one “galuminium” rib.
How to calculate the number of radiators
How to calculate the number of heating radiator sections is one of the main problems people face when replacing an update system.
There are several approaches to calculating and each of them will probably find its own grateful 
viewer.
The standard method for calculating the number of heating radiators
According to " Building codes and rules "one square meter of living space requires 100 watts of heating radiator power.
In this case, the required power is calculated using the following formula:
S * 100 / P, where
S = room area
P = power of one heating radiator section
For example, the power of one section of the radiator you choose is 180 watts, and the area of the room is 20 square meters, in this case:
20*100/180=11,11
This means that to heat a living room of 20 sq / m, 11 sections of a heating radiator will be required.
The formula has amendments! If the room is located at the end or, then the resulting amount must be multiplied by 1.2. In our case, there would be 13 sections for a corner room.
Method of calculating the number of heating radiators "by eye" 
Almost all sectional radiators heating have standard sizes, plus or minus for special cases. Therefore, with a ceiling height of approximately 2.5 meters (up to 2.7), one section is required for 1.8 square meters of living space.
For example, for the same "our" room of 20 square meters you will need:
20/1,8=11,11
11 radiator sections.
But keep in mind, when low power purchased heating device, this method of calculation is invalid and ineffective!
Volumetric calculation of the number of heating radiators
In this case, we count by the volume of the heated room. As is known from the geometry of the school level, three parameters are involved in the calculation - length, width, height.
If we want to install a bimetallic heating radiator with a capacity of 200 watts in each section, then one section of it will heat 5 cubic meters of the room. Further, a simple calculation using the example of "our" room, which is 4 meters wide, 5 meters long and 2.5 meters high:
(4*5*2,5)/5=10
It turns out that such a room requires 10 sections of a bimetallic radiator of 200 watts.
What else you need to know when calculating the number of sections in a heating radiator
Standard power sections are in the 120-220 watts range. Check with the seller.
When buying and calculating, take into account various random factors, so it is better to "stock up" with heat 20% more than the calculated level. Either due to the power of the sections, or due to their number, so that later it would not be excruciatingly cool in winter.
And, the last thing, of course, when installing and installing a heating radiator, it is still better to turn to professional people who will be able to evaluate everything in full regarding the calculation of the number of sections.
Many owners of private houses and summer cottages are faced with the problem of calculating the number of radiator sections. First of all, it is necessary to ensure quality heating... Also, the exact number of sections and the batteries themselves will save money on purchase, installation costs and the choice of a boiler for heating the coolant, namely its power.
Heating radiators are used to ensure maximum comfortable temperature within the premises, the main task is not so much to heat the air as to maintain its temperature. That is why the batteries are located on external walls ah, and not interroom and almost always under windows - to create a heat-temperature barrier for cold inflow and outflow warm air across window frames and pay off the percentage of heat loss.
What is an accurate calculation for?
Before calculating the number of heating radiator sections, it will be useful to know the purpose of this operation. Most often this is an economic benefit and ensuring the required level of temperature in the room.
Ensuring a comfortable temperature in the house
Providing a certain constant temperature indoors - the most obvious answer to the question of why it is necessary to calculate the number of heating radiator sections. The room temperature will depend not only on the power of the battery, but also on a number of other parameters:
- coolant temperature in the radiator;
- the degree of home insulation;
- temperature outside the window;
- type of radiators;
- the area of the room;
- ceiling heights.
Upon further consideration of the calculation formulas most of these parameters will appear in them.
Energy saving
Regardless of the type of energy carrier with which the house is heated (gas, electricity or solid fuel), its excessive consumption gives not only too much high temperature indoors, but also leads to increased costs. Therefore, the calculation of heating radiators can significantly save energy costs.
A simple way to calculate radiators by area
In power calculation heating device and the number of its sections can take part a large number of parameters. Calculation of heating batteries for an area is the easiest way, even a person without special education, which has nothing to do with heating technology.
The essence of this method is that for 1 square meter of the heated area there should be 100 W of the power of the heating device. In this case, the number of battery sections will be calculated according to the following algorithm: N = (S * 100) / P, where S is the area of the heated room, N is the number of radiator sections, P is the power of each section.
It should be noted that this formula relevant for typical houses with a ceiling height of 2.5 meters. If the heated room is in a corner or there is a large window and a balcony in it, then the calculation result is recommended to be corrected by 20%.
Accurate methods for calculating heating radiators
If the heated room does not belong to a typical one, then it is better to refuse the averaged formula for calculating heating radiators. If the ceiling height exceeds 2.5 meters, then it is more expedient to use the calculation formula, which does not depend on the area, but on the volume of the heated room. It will not be difficult to find out the volume of the room - you just need to multiply its area by the height. Construction standards state that 41 watts of radiator power should be accounted for per cubic meter of heated area.
Then the formula for calculating the number of radiator sections is as follows: N = S * H * 41 / P, where S is the area of the room, H is the height of the room, N is the number of radiator sections, P is the power of one section.
The calculation of the number of heating radiator sections in a private house should take into account the quality of the glazing window openings, the degree of home insulation and other parameters. In this case, the calculation formula looks like this N = 100 * S * K1 * K2 * K3 * K4 * K5 * K6 * K7 / P, where:
- N is the number of radiator sections;
- S is the area of the heated room;
- K1 - glazing coefficient (for a regular window it is 1.27; for a double-glazed unit with two glasses - 1; for a triple - 0.87);
- K2 - coefficient of house insulation, with poor insulation - equal to 1.27; with a satisfactory -1; with good - 0.85;
- K3 is the ratio of window area to floor area (50% coefficient is 1.2; 40% - 1.1, 30% -1; 20% - 0.9; 10% - 0.8);
- K4 - temperature coefficient, taking into account the average temperature in the room in the coldest week (at 35 degrees, it will be equal to 1.5; at 25 - 1.3; at 20 - 1.1; at 15 degrees - 0.9; at 10 - 0.7);
- K5 - accounting for the number of external walls (for a room with one wall, the coefficient is 1.1; for a room with two walls - 1.2; with three - 1.3);
- K6 is a coefficient taking into account the nature of the room on the floor above (for an unheated attic, the coefficient is equal to one, for a heated utility room - 0.9; for a heated room - 0.7);
- K7 - coefficient taking into account the height of the ceilings (for standard height ceilings of 2.5 m, the coefficient is equal to one; 3 meters - 1.05; 3.5 m - 1.1; 4 m - 1.15).
Any of these parameters, in which you are unsure, should be taken as a unit, thus it is excluded from the calculation and is considered standard.
Calculating the number of radiators using a calculator
Performing calculations using any of the above formulas will take a little time and skill with numbers. If you do not have a penchant for the exact sciences and free time, then it is more advisable to use a specially designed calculator.
If it was decided to calculate the heating in a private house, the calculator will become irreplaceable assistant... In it, you select the parameters of your home that affect the power of the heating device, and the program automatically applies the coefficients:
- area of the room;
- ceiling height;
- temperature;
- glazing;
- the number of external walls and other factors.
You just have to enter all these parameters and in an instant get the desired figure in order to calculate the number of heating radiator sections for your room.
It is worth noting that the calculator uses the same algorithms and formulas for calculating that were given above, so software and independent calculations do not differ in quality at all.
Outcome
Calculate the number of radiator sections as accurately as possible and take into account as many factors and criteria as possible. This will ensure maximum comfort in the house and minimum costs for energy.
How many sections should there be in a radiator?
Having lived at least the winter, each time we set ourselves the same goal - to a new heating season prepare as productively as possible by replacing old radiators with more efficient ones. Choosing a heater, you still need to be correct. This is easy to do if you know the formula.
For correct calculations, you will need to measure the dimensions of the room and calculate its area. It is important to consider where the room is located - surrounded by other rooms or away from them, determine the thickness of the walls and the material from which they are made, pay attention to the number of windows and the quality of thermal insulation.
Standard calculation
Many complain that even after installing new batteries, the house is still uncomfortable and cold. Experts are sure that the point is not that the devices did not meet the expectations of consumers. More often than not, the cause is the wrong one. There are standard schemes that take into account the requirements of SNiP. They indicate that heating 1 square meter of living space requires 100 W of heating device power.
From here you can derive a simple formula:
K (number of batteries) = S (area of the room) multiplied by 100 and divided by P (power of one battery section). The last value is indicated in the technical data sheet of the product.
Here's a simple example of how this formula can be applied. Let's say there is a room with an area of 22 square meters... 22 × 100/200 = 11
An 11-section radiator must be selected for this room. And then according to the circumstances. If the room is corner, add 20% to the stock and get a little more - 13. Using this scheme, you can calculate almost all radiators - both cast iron and bimetallic.
Volumetric calculation of the number of sections
You can calculate the number of required sections based on the volume of the radiator. If a house or apartment was built without taking into account the currently fashionable energy saving technologies, then 1 cubic meter volume requires 41 watts of thermal power.
This scheme is used in Europe. Dividing the available volume of the room by 41, we get the required power of the device. Knowing it and the same indicator for one section of the battery, it is easy to calculate the sectional number of the device.
Let's give an example assuming that the room has an area of 22 square meters and a ceiling height of 2.7 m.The cubic volume is calculated as follows:
State-of-the-art combination battery
The power of one radiator unit, depending on the model, can vary from 120 to 200 watts. Here are some examples of calculation:
- If this value is equal to 120 W (the parameters are indicated in the passport), then the calculation formula is as follows - 1448/120 = 12.06 (12-section battery).
- If the power of one unit of the device is 250 W, then the following figures are obtained - 1448/250 = 5.8 (6-section battery). The calculation principle is generally clear.
As a rule, shop assistants are aware of the power of the heater. It is known that for one section cast iron unit this figure is 160 W, aluminum - 192 W, bimetallic - 200 W. Knowing these values, you can make accurate calculations in advance before buying.
Note! Since winters in our latitudes can be very harsh, experts advise adding an extra 20% to the exact calculations. This means that you always need to add 2 extra units to the figure you received indicating the sectionality of the device.
Generalization on the topic
Now you know how to solve the problem at hand. There are two schemes that allow you to find the answer to the question of the number of radiator sections with mathematical precision. Experts recommend that you study the technical data sheet of the product in detail and do not hesitate to ask the sellers when purchasing heating devices.