How to calculate the power of a bimetallic battery. Calculation of the number of sections of a bimetallic radiator. Simple and fast calculation method
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Most often, owners purchase bimetallic radiators for replacement. cast iron batteries, which for one reason or another failed or began to heat the room poorly. In order for this model of radiators to cope well with its task, you need to familiarize yourself with the rules for calculating the number of sections for the entire room.
Necessary data for calculation
Himself the right decision will be an appeal to experienced specialists. Professionals can calculate the amount bimetallic radiators heating is quite accurate and efficient. This calculation will help determine how many sections will be needed not only for one room, but for the entire room, as well as for any type of object.
All professionals take into account the following data to calculate the number of batteries:
- what material was the building made of;
- what is the thickness of the walls in the rooms;
- the type of windows that were installed in this room;
- in what climatic conditions is the building located?
- is there any heating in the room above the room where the radiators are installed;
- how many “cold” walls are there in the room;
- what is the area of the calculated room;
- what is the height of the walls?
All this data allows us to make the most accurate calculation for installing bimetallic batteries.
Heat loss coefficient
To make the calculation correctly, you must first calculate what will be heat losses, and then calculate their coefficient. For accurate data, one unknown must be taken into account, that is, the walls. This applies, first of all, corner rooms. For example, the following parameters are presented in the room: height - two and a half meters, width - three meters, length - six meters.
- F is the area of the wall;
- a – its length;
- x – its height.
The calculation is carried out in meters. According to these calculations, the wall area will be equal to seven and a half square meters. After this, it is necessary to calculate heat loss using the formula P = F*K.
Also multiply by the difference in temperature indoors and outdoors, where:
- P is the area of heat loss;
- F is the area of the wall in square meters;
- K is the thermal conductivity coefficient.
For correct calculation temperature must be taken into account. If the temperature outside is approximately twenty-one degrees, and in the room eighteen degrees, then to calculate of this premises you need to add two more degrees. To the resulting figure you need to add P windows and P doors. The result obtained must be divided by the number indicating the thermal power of one section. As a result simple calculations and you will be able to find out how many batteries are needed to heat one room.
However, all these calculations are correct only for rooms that have average insulation rates. As you know, there are no identical rooms, so for an accurate calculation it is necessary to take into account the correction factors. They need to be multiplied by the result obtained using the formula. The correction coefficient for corner rooms is 1.3, for rooms located in very cold places - 1.6, for attics - 1.5.
Battery power
To determine the power of one radiator, it is necessary to calculate how many kilowatts of heat will be needed from installed system heating. The power needed to heat each square meter is 100 watts. The resulting number is multiplied by the number of square meters of the room. The figure is then divided by the power of each individual section of a modern radiator. Some battery models consist of two or more sections. When making calculations, you need to choose a radiator that has a number of sections close to ideal. But still, it should be a little more than calculated.
This is done in order to make the room warmer and not freeze on cold days.
Manufacturers of bimetallic radiators indicate their power for certain heating system data. Therefore, when buying any model, it is necessary to take into account the thermal pressure, which characterizes how the coolant is heated, as well as how it heats the heating system. IN technical documentation The power of one section is often indicated for a heat pressure of sixty degrees. This corresponds to a water temperature in the radiator of ninety degrees. In those houses where the rooms are heated with cast iron radiators, this is justified, but for new buildings, where everything is more modern, the temperature of the water in the radiator may well be lower. The heat pressure in such heating systems can be up to fifty degrees.
The calculation here is also not difficult. You need to divide the power of the radiator by the number indicating the thermal pressure. The number is divided by the figure indicated in the documents. In this case, the effective power of the batteries will be slightly less.
It is this that must be included in all formulas.
Popular methods
To subtract the required number of sections in the installed radiator, not one formula, but several can be used. Therefore, it is worth evaluating all the options and choosing the one that is suitable for obtaining more accurate data. To do this, you need to know that according to SNiP standards, per 1 m², one bimetallic section can heat one meter and eighty centimeters of area. To calculate how many sections are needed for 16 m², you need to divide this figure by 1.8 square meters. The result is nine sections. However, this method is quite primitive and for more precise definition All the above data must be taken into account.
There is another simple method for doing the calculation yourself. For example, if we take small room 12 m², then very strong batteries are of no use here. You can take, for example, the heat transfer of just one section is two hundred watts. Then using the formula you can easily calculate the number required for the selected room. To get the desired figure, you need 12 - this is the number of squares, multiply by 100, power per square meter and divide by 200 watts. This, as you can understand, is the heat transfer value per section. As a result of the calculations, the number six will be obtained, that is, exactly how many sections will be needed to heat a room of twelve squares.
You can consider another option for an apartment with an area of 20 m². Let’s assume that the power of the section of the purchased radiator is one hundred and eighty watts. Then, substituting all the available values into the formula, you get the following result: 20 needs to be multiplied by 100 and divided by 180 will equal 11, which means that this number of sections will be needed to heat a given room. However, such results will really correspond to those rooms where the ceilings are no higher than three meters and the climatic conditions are not very harsh. And also the windows, that is, their number, were not taken into account, so it is necessary to add several more sections to the final result, their number will depend on the number of windows. That is, you can install two radiators in a room, each with six sections. In this calculation, another section was added taking into account windows and doors.
By volume
To make the calculation more accurate, you need to calculate by volume, that is, take into account three measurements in the selected heated room. All calculations are done almost the same way, only the basis is the power data calculated per cubic meter, which is equal to forty-one watts. You can try to calculate the number of sections bimetallic battery for a room with the same area as in the option discussed above, and compare the results. In this case, the ceiling height will be two meters and seventy centimeters, and the square footage of the room will be twelve square meters. Then you need to multiply three by four, and then by two and seven.
The result will be this: thirty-two and four cubic meters. It must be multiplied by forty-one and you get one thousand three hundred twenty-eight and four watts. This radiator power will be ideal for heating this room. Then this result must be divided by two hundred, that is, the number of watts. The result will be equal to six point six four hundredths, which means you will need a radiator with seven sections. As you can see, the result of the volume calculation is much more accurate. As a result, you won’t even need to take into account the number of windows and doors.
You can also compare the calculation results in a room with twenty square meters. To do this, you need to multiply twenty by two and seven, you get fifty-four cubic meters - this is the volume of the room. Next, you need to multiply by forty-one and the result is two thousand four hundred and fourteen watts. If the battery has a power of two hundred watts, then this figure must be divided by the result obtained. As a result, you will get twelve and seven, which means that for this room you need the same number of sections as in the previous calculation, but this option is much more accurate.
Bimetal radiators, consisting of steel and aluminum parts, are most often purchased as a replacement for failed cast iron batteries. Outdated models of heating devices cannot cope with their main task - good heating premises. In order for the purchase to be of any use, you need to do correct calculation sections of bimetallic heating radiators according to the area of the apartment. How to do it? There are several ways.
Simple and fast calculation method
Before you start replacing old batteries with new radiators, you need to make the correct calculations. All calculations are carried out based on the following considerations:
- Keep in mind that the heat dissipation of a bimetallic radiator will be slightly higher than that of a cast iron counterpart. With a high-temperature heating system (90 °C), the average figures will be 200 and 180 W, respectively;
- It’s okay if the new heating device heats up a little more powerfully than the old one, it’s worse if it’s the other way around;
- Over time, the efficiency of heat transfer will decrease slightly due to blockages in the pipes in the form of deposits of products of the active interaction of water and metal parts.
From everything written above, one conclusion can be drawn - the number of sections of a new bimetallic radiator should be no less than that of a cast iron one. In practice, it usually happens that they install a battery literally 1-2 sections larger - this is a necessary reserve, which will not be superfluous, given the last point of the list above.
Power calculations based on room dimensions
It doesn't matter whether you decide to install radiators in completely new apartment, or you are replacing old items left over from Soviet times, you need to calculate the sections of bimetallic heating radiators. So, what computational methods exist to select a battery? required power? Taking into account the dimensions of the apartment, calculations are made taking into account either area or volume. Last option more accurate, but first things first.
Plumbing standards in force throughout Russia define minimum values power of heating devices per 1 square meter dwellings. This value is 100 W (under conditions middle zone Russia).
Calculation of bimetallic heating radiators per square meter of room is very simple. Measure the length and width of the room with a tape measure and multiply the resulting values. Multiply the resulting number by 100 W and divide by the heat transfer value for one section.
For example, let's take a room of 3x4 m, this is a small room, and very powerful heaters are not needed here. Here calculation formula: K = 3x4x100/200 = 6. In the example given, the heat output of 1 section of the battery is taken to be 200 W.
- the results will be close to maximum accuracy only if the calculations are carried out for a room with ceilings no higher than 3 meters;
- This calculation does not take into account important factors - the number of windows, dimensions doorways, presence of insulation in the floor and walls, wall material, etc.;
- the formula is not suitable for places with extreme low temperatures in winter, for example, for Siberia and the Far East.
Calculations of sections will be more accurate if all three dimensions are taken into account in the calculations - the length, width and height of the room; in other words, you need to calculate the volume. The calculation is carried out using a similar algorithm as in the previous case, but other values should be taken as a basis. Sanitary standards, set for heating at 1 cubic meter- 41 W.
- The volume of the room is: V = 3x4x2.7 = 32.4 m3
- The battery power is calculated by the formula: P = 32.4x41 = 1328.4 W.
- Calculation of the number of cells, formula: K = 1328.4/20 = 6.64 pcs.
The number obtained as a result of calculations is not an integer, so it must be rounded to big side- 7 pcs. By comparing the values, it is easy to discover that the latter method is more accurate and efficient than calculating battery sections by area.
How to calculate heat losses
More exact calculation will require taking into account one of the unknowns - walls. This is especially true for corner rooms. Let’s assume that the room has the following parameters: height - 2.5 m, width - 3 m, length - 6 m.
Object of calculation in in this case is the outer wall. Calculations are made using the formula: F = a*h.
- F - wall area;
- a - length;
- h - height;
- unit of account is meter.
- According to calculations, it turns out F = 3x2.5 = 7.5 m2. Square balcony doors and windows is subtracted from total area walls.
- The area has been found, all that remains is to calculate the heat loss. Formula: Q = F*K*(tin + tout).
- F - wall area (m2);
- K is the coefficient of thermal conductivity (its value can be found in SNiPs; for these calculations the value taken is 2.5 (W/m2).
Q = 7.5x2.5x(18+(-21)) = 56.25. The result obtained is added to the other heat loss values: Qroom. = Qwalls+Qwindows+Qdoors. The final number obtained during the calculations is simply divided by the thermal power of one section.
Formula: Qroom/Nsections = number of battery sections.
Correction factors
All the above formulas are accurate only for the middle zone of the Russian Federation and interior spaces with average insulation rates. In reality, absolutely identical rooms do not exist; in order to obtain the most accurate calculation, it is necessary to take into account correction factors, by which the result obtained from the formulas should be multiplied:
- corner rooms - 1.3;
- Far North, Far East, Siberia - 1.6;
- take into account the place where the heating device will be installed, decorative screens and the boxes conceal up to 25% of the thermal power, and if the battery is also in a niche, then add an additional 7% to energy losses;
- the window requires an increase of 100 W of power, and doorway- 200 W.
For country house the result obtained during the calculations is additionally multiplied by a factor of 1.5 - the attic without heating is taken into account and external walls buildings. However, bimetal batteries are more often installed in apartment buildings, than in private ones due to the high cost, especially compared to batteries made of aluminum.
Effective power accounting
One more parameter cannot be discounted when making calculations about radiators. The documents enclosed with the heater indicate battery power values depending on the type heating system. When choosing heating batteries, take into account the thermal pressure - roughly speaking, this temperature regime coolant supplied to the system heating the house.
In documents for a heating device, a power for a pressure of 60 °C is often found; this value corresponds to a high-temperature heating mode of 90 °C (the temperature of the water supplied to the pipes). This is true for old houses with systems that were in operation during Soviet times. In modern new buildings, heating technologies of a different type are no longer required for full heating. high temperatures coolant in the pipes. Thermal pressure in new houses is significantly lower - 30 and 50 °C.
To calculate bimetallic heating radiators for an apartment, you need to make simple calculations: multiply the power calculated using the previous formulas by the value of the actual thermal pressure and divide the resulting number by the value indicated in the data sheet. As a rule, such calculations reduce the effective power of radiators.
Take this into account when making calculations - in all formulas, substitute the effective power value that corresponds to the actual thermal pressure in the heating system of your home.
When making calculations, be guided by simple, but important rule- it’s better to make a slightly larger mistake than to endure the cold due to errors in calculations. Russian winters are unpredictable and can be record cold even in the middle zone of the country, so a small reserve of 10% will not be superfluous. To regulate the heat supply, install two taps - one on the bypass, and the second to shut off the coolant supply. By adjusting the taps, you can control the temperature in the room.
Results
So to carry it all out necessary calculations and choose a radiator with a power suitable for your home, use the given calculation formulas, they are simple and quite accurate. The main nuance - exact value actual power of your heating system. By spending a little time with a calculator in your hands, you will avoid mistakes when purchasing heating device, and in winter time your home will always maintain a comfortable temperature.
In the matter of maintaining optimal temperature In the house, the main place is occupied by the radiator.
The choice is simply amazing: bimetallic, aluminum, steel in a variety of sizes.
There is nothing worse than an incorrectly calculated necessary thermal power in room. In winter, such a mistake can be very costly.
Thermal calculation of heating radiators is suitable for bimetallic, aluminum, steel and cast iron radiators. Experts distinguish three methods, each of which is based on certain indicators.
There are three methods that are based on general principles:
- the standard power value of one section can vary from 120 to 220 W, so the average value is taken
- To correct errors in calculations when purchasing a radiator, a 20% reserve should be included
Now let's turn directly to the methods themselves.
Method one - standard
Based building regulations, For quality heating One square meter requires 100 watts of radiator power. Let's do the calculations.
Let's say the area of the room is 30 m², let's take the power of one section equal to 180 watts, then 30*100/180 = 16.6. Let's round the value up and find that for a room of 30 square meters you need 17 sections of a heating radiator.
However, if the room is corner, then the resulting value should be multiplied by a factor of 1.2. In this case, the quantity necessary sections there will be 20 radiators
Method two - approximate
This method differs from the previous one in that it is based not only on the area of the room, but also on its height. Please note that the method only works for medium and high power devices.
At low power(50 watts or less), such calculations will be ineffective due to too large an error.
So, if we take into account that the average height of the room is 2.5 meters ( standard height ceilings of most apartments), then one section of a standard radiator is capable of heating an area of 1.8 m².
The calculation of sections for a room of 30 “squares” will be as follows: 30/1.8=16. We round up again and find that to heat this room you need 17 radiator sections.
Method three - volumetric
As the name implies, calculations in this method are based on the volume of the room.
It is conventionally accepted that to heat 5 cubic meters of space you need 1 section with a power of 200 watts. With a length of 6 m, a width of 5 and a height of 2.5 m, the formula for calculation will be as follows: (6*5*2.5)/5 =15. Therefore, for a room with such parameters you need 15 sections of a heating radiator with a power of 200 watts each.
If the radiator is planned to be located in a deep open niche, then the number of sections should be increased by 5%.
If the radiator is planned to be completely covered with a panel, the increase should be made by 15%. Otherwise, it will be impossible to achieve optimal heat transfer.
An alternative method for calculating the power of heating radiators
Calculating the number of sections of heating radiators is far from the only way proper organization heating the room.
Let's calculate the volume of the proposed room with an area of 30 square meters. m and a height of 2.5 m:
30 x 2.5 = 75 cubic meters.
Now we need to decide on the climate.
For the territory of the European part of Russia, as well as Belarus and Ukraine, the standard is 41 watts of thermal power per cubic meter of room.
For determining required power multiply the volume of the room by the standard:
75 x 41 = 3075 W
Let's round the resulting value up - 3100 watts. For those people who live in very cold winters, this figure can be increased by 20%:
3100 x 1.2 = 3720 W.
When you come to the store and check the power of the heating radiator, you can calculate how many radiator sections will be required to maintain comfortable temperature even in the harshest winter.
Calculation of the number of radiators
The calculation method is an excerpt from the previous paragraphs of the article.
After you calculate the required power to heat the room and the number of radiator sections, you come to the store.
If the number of sections is impressive (this happens in rooms with large area), then it would be reasonable to purchase not one, but several radiators.
This scheme is also applicable to those conditions when the power of one radiator is lower than necessary.
But there is another one quick way count the number of radiators. If in your room there were old ones with a height of about 60 cm, and in winter you felt comfortable in this room, then count the number of sections.
Multiply the resulting figure by 150 W - this will be the required power of the new radiators.
If you choose or, you can buy them at the rate of 1 to 1 - for one fin of a cast iron radiator 1 bimetallic fin.
The division into “warm” and “cold” apartments has long come into our lives.
Many people deliberately do not want to select and install new radiators, explaining that “it will always be cold in this apartment.” But that's not true.
The correct choice of radiators, coupled with a competent calculation of the required power, can create warmth and comfort outside your windows even in the coldest winter.
The calculation of radiators must be done correctly, otherwise a small number of them will not be able to sufficiently warm the room, and a large number, on the contrary, will create uncomfortable living conditions, and you will have to constantly open the windows. Known different techniques calculation. Their choice is influenced by the material of the batteries, climatic conditions, and home furnishings.
Calculation of the number of batteries per 1 sq. m
The area of each room where radiators will be installed can be viewed in the real estate documents or measured independently. The heat requirement for each room can be found in building codes, where it is stated that to heat 1m2 in a certain residential area you will need:- for the harsh climatic conditions(temperature reaches below -60 degrees) – 150-200 W;
- for the middle band - 60-100 W.
16 x 100 = 1600 W
Taken the most higher value power consumption, since the weather is changeable, and it is better to provide a small reserve of power so as not to freeze later in the winter.
Next, the number of battery sections (N) is calculated - the resulting value is divided by the heat generated by one section. It is assumed that one section emits 170 W, based on this, the calculation is carried out:
1600 / 170 = 9,4
It is better to round up - 10 pieces. But for some rooms it makes more sense to round down, for example, for the kitchen, which has additional heat sources. Then there will be 9 sections.
Calculations can be carried out using another formula, which is similar to the calculations presented above:
N = S/P * 100, where
- N – number of sections;
- S – room area;
- P – heat transfer of one section.
Selecting the exact number of sections of bimetallic batteries
They come in several types, each of them has its own power. The minimum heat generation reaches 120 W, the maximum is 190 W. When calculating the number of sections, you need to take into account the required heat consumption depending on the location of the house, as well as taking into account heat loss:- Drafts that occur due to poorly executed window openings and profiles of windows, cracks in walls.
- Waste of heat along the path of the coolant from one battery to another.
- Corner location of the room.
- Number of windows in the room: the more there are, the greater the heat loss.
- Regular ventilation of rooms in winter also affects the number of sections.
Calculation of the number of radiators in a private house
If for apartments you can take the average parameters of heat consumption, since they are designed for standard dimensions rooms, then in private construction this is wrong. After all, many owners build their houses with a ceiling height exceeding 2.8 meters, in addition, almost all private premises are corner, so more power will be required to heat them.In this case, calculations based on taking into account the area of the room are not suitable: you need to apply the formula taking into account the volume of the room and make adjustments using coefficients for reducing or increasing heat transfer.
The coefficient values are as follows:
- 0,2 – the resulting final power number is multiplied by this indicator if multi-chamber plastic double-glazed windows are installed in the house.
- 1,15 – if the boiler installed in the house is operating at its capacity limit. In this case, every 10 degrees of heated coolant reduces the power of the radiators by 15%.
- 1,8 – the magnification factor that needs to be applied if the room is corner and has more than one window.
P = V x 41, where
- V – volume of the room;
- 41 – average power required to heat 1 sq. m of a private house.
If you have a room of 20 sq. m (4x5 m – wall length) with a ceiling height of 3 meters, then its volume is easy to calculate:
20 x 3 = 60 W
The resulting value is multiplied by the power accepted by the standards:
60 x 41 = 2460 W - this is how much heat is required to heat the area in question.
Calculation of the number of radiators comes down to the following (taking into account that one radiator section emits on average 160 W, and their exact data depends on the material from which the batteries are made):
2460 / 160 = 15.4 pieces
Let's assume that a total of 16 sections are needed, that is, you need to purchase 4 radiators of 4 sections for each wall or 2 of 8 sections. At the same time, one should not forget about the adjustment coefficients.
Calculation of heat transfer from one aluminum radiator (video)
In the video you will learn how to calculate the heat transfer of one section of an aluminum battery at different parameters incoming and outgoing coolant.One section aluminum radiator has a power of 199 watts, but this is provided that the declared temperature difference is 70 degrees. will be respected. This means that the coolant temperature at the inlet is 110 degrees, and at the outlet 70 degrees. With such a difference, the room should warm up to 20 degrees. This temperature difference is designated DT.
Some radiator manufacturers provide a heat transfer conversion table and coefficient along with their product. Its floating value: than more topics The temperature of the coolant, the greater the heat transfer rate.
As an example, you can calculate this parameter with the following data:
- The coolant temperature at the radiator inlet is 85 degrees;
- The cooling of water when leaving the radiator is 63 degrees;
- Heating of the room - 23 degrees.
(85 + 63) / 2 – 23 = 52
The resulting number is equal to DT; from the proposed table it can be established that its coefficient is 0.68. Taking this into account, we can determine the heat transfer of one section:
199 x 0.68 = 135 W
Then, knowing the heat loss in each room, you can calculate how many radiator sections are needed for installation in a certain room. Even if, according to calculations, the result is one section, you need to install at least 3, otherwise the entire heating system will look ridiculous and will not warm the area sufficiently.
Calculating the number of radiators is always relevant. To those who build a private house, this is especially important. Apartment owners who want to change radiators should also know how to easily calculate the number of sections on new radiator models.
The main task of any heating battery is to heat the room. For these reasons, heat transfer is main parameter, which is worth considering when purchasing. For each model of heating devices, the heat transfer values are different, including for bimetal. This parameter is affected by the volume and number of sections.
So, what is the power of 1 section of bimetallic heating radiators? Knowing the value, you can correctly calculate required size device.
What is heat transfer
The definition of heat transfer comes down to steam simple words- this is the amount of heat generated by the radiator over a certain time. Radiator power, thermal power, heat flow - the designation of one concept and is measured in Watts. For 1 section of a bimetallic radiator, this number is 200 W.
Some documents contain heat transfer values calculated in calories per hour. To avoid confusion, calories are easily converted to Watts using simple calculations (1 Watt = 859.8 cal/hour).
Heat from the battery warms the room through three processes:
- heat exchange;
- convection;
- radiation.
Each model of heating devices uses all types of heating, but in different proportions. For example, a radiator is considered to be those batteries that transfer 25% of thermal energy into the surrounding space through radiation. But now the term “radiator” has begun to be used to describe any heating device, regardless of the main heating method.
Dimensions and capacity of sections
Bimetallic radiators, due to steel inserts, are more compact than aluminum, cast iron, and steel models. To some extent, this is not bad; the smaller the section, the less coolant is required for heating, which means that the battery is more economical in terms of heat energy consumption. However, too narrow pipes quickly become clogged with debris and rubbish, which are inevitable companions in modern heating networks.
U good models radiators made of bimetal, the thickness of the steel cores inside is the same as that of the walls of a regular one water pipe. The heat transfer of the battery depends on the capacity of the sections, and the interaxial distance directly affects the capacity parameters:
- 20 cm - 0.1-0.16 l;
- 35 cm - 0.15-0.2 l;
- 50 cm - 0.2-0.3 l.
From the given data it follows that bimetal radiators require a small amount of coolant. For example, a heating device made of ten sections 35 cm high and 80 cm wide holds only 1.6 liters. Despite this, the heat flow is sufficient to warm the air in a room of 14 square meters. m. It is worth considering that a battery of this size weighs almost twice as much as its aluminum counterparts - 14 kg.
The vast majority of bimetal batteries can be purchased in specialized stores in one section and assembled a radiator of exactly the size required by the room. This is convenient, although there are one-piece models with a fixed number of sections (usually no more than 14 pieces). Each part has four holes: two inlets and two outlets. Their sizes may vary depending on the model of the heating device. To make it easier to assemble bimetal radiators, two holes are made with right-hand threads, and two with left-hand threads.
How to choose the right number of sections
The heat output of bimetallic heating devices is indicated in the data sheet. Based on this data, all necessary calculations are made. In cases where the heat transfer value is not indicated in the documents, these data can be viewed on the official websites of the manufacturer or used in the calculations the average value. For each individual room, its own calculation must be carried out.
To calculate the required number of bimetal sections, you need to take into account several factors. The heat transfer parameters of bimetal are slightly higher than those of cast iron (taking into account the same operating conditions. For example, let the coolant temperature be 90 ° C, then the power of one section of bimetal is 200 W, of cast iron - 180 W).
If you are planning to change cast iron radiator to bimetallic, then with the same dimensions new battery It will heat up a little better than the old one. And this is good. It is worth considering that over time the heat transfer will be slightly less due to blockages inside the pipes. Batteries become clogged with deposits that appear due to metal contact with water.
Therefore, if you decide to replace it, then calmly take the same number of sections. Sometimes batteries are installed with a small margin in one or two sections. This is done to avoid loss of heat transfer due to clogging. But if you are purchasing batteries for a new room, you cannot do without calculations.
Calculation by dimensions
The heat output of radiators depends on the volume of the room that needs to be heated. How bigger room, the more sections required. Therefore, the simplest calculation is based on the area of the room.
There are special standards for plumbing, strictly regulated by SNiP. Batteries are no exception. For buildings in a temperate climate zone, the standard heating power is 100 W per square meter of room. Having calculated the area of the room, multiplying the width by the length, you must also multiply the resulting value by 100. This will give you the total heat transfer of the battery. All that remains is to divide it into the heat transfer parameters of the bimetal.
For a 3x4 m room, the calculation will look like this:
K = 3x4x100/200 = 6 pcs.
The formula is extremely simple, but allows you to calculate only the approximate number of bimetal sections. These calculations do not take into account such important parameters How:
- ceiling height (the formula is more or less accurate for ceilings no higher than 3 m);
- room location ( north side, corner of the house);
- number of window and door openings;
- degree of insulation of external walls.
Calculation by volume
Calculating the heat transfer of a battery by room volume is a little more complicated. To do this, you will need to know the width, length and height of the room, as well as the heating standards established for one m 3 - 41 W.
What heat transfer should bimetallic radiators have for a room 3x4 m, taking into account the ceiling height of 2.7 m: V = 3x4x2.7 = 32.4 m 3.
Having received the volume, it is easy to calculate the heat transfer of the battery: P = 32.4x41 = 1328.4 W.
As a result, the number of sections (taking into account the thermal power of the battery at high temperature mode 200 W) will be equal to: K = 1328.4/200 = 6.64 pcs.
The resulting number, if it is not an integer, is always rounded up. Based on more accurate calculations, you will need 7 sections, not 6.
Correction factors
Despite the same values in the data sheet, the actual heat transfer of radiators may differ depending on operating conditions. Considering that the above formulas are accurate only for houses with average insulation rates and for areas with a temperate climate, under other conditions it is necessary to introduce amendments to the calculations.
To do this, the value obtained during the calculations is additionally multiplied by a coefficient:
- corner and northern rooms - 1.3;
- regions with extreme frosts (Far North) - 1.6;
- screen or box - add another 25%, niche - 7%;
- for each window in the room, the total heat transfer for the room increases by 100 W, for each door - 200 W;
- cottage - 1.5;
Important! The last coefficient when calculating bimetallic radiators is used extremely rarely, because such heating devices are almost never installed in private homes due to their high cost.
Efficient heat dissipation
Thermal output values for radiators are indicated in the data sheet or on the manufacturers' websites. They are suitable for specific parameters heating systems. Thermal pressure of the system - important characteristic, which cannot be ignored when performing the necessary calculations. Typically, the heat transfer value of section 1 is given for a thermal pressure of 60°C, which corresponds to the high-temperature regime of a heating system with a water temperature of 90°C. Such parameters are now found in old houses. For new buildings more than modern technologies, in which high thermal pressure is no longer required. Its value for the heating system is 30 and 50° C.
Because of different meanings thermal pressure in the data sheet and in fact, it is necessary to recalculate the power of the sections. In most cases it turns out to be lower than stated. The heat transfer value is multiplied by real value thermal pressure and divide by what is indicated in the documents.
The output parameters of one section of a bimetallic heating battery directly affect its dimensions and ability to heat the room. It is impossible to make accurate calculations without knowing the heat transfer value of the bimetal.
Photo gallery (11 photos)
Bimetallic heating radiator