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Calculation of heat energy for heating. Thermal calculation of the heating system: how to correctly calculate the load on the system

In a private house, you need to do everything yourself (specialist) "hands", including counting, designing, buying and installing a heating system. In order to start the organization of communications in the house, it is necessary to make a thermal calculation of the heating system. Below is explained how and why it is done.

Classic heat calculation heating system is a consolidated technical document that includes mandatory step-by-step standard methods of calculation.

But before studying these calculations of the main parameters it is necessary to determine the concept of the heating system itself.

Heating - a multicomponent system to ensure an approved temperature in the room / building. Is a separate part of the complex of communications of modern housing

The heating system is characterized by forced delivery and involuntary heat dissipation in the room. The main tasks of calculating and designing a heating system:

the most reliable is to determine the heat loss
determine the quantity and conditions of use of the coolant
as accurately as possible to choose elements of generation, movement and return of heat

When building a heating system, you must first collect a variety of data about the room / building where the heating system will be used. After calculating the thermal parameters of the system, analyze the results of arithmetic operations. Based on the data obtained, select the components of the heating system with the subsequent purchase, installation and commissioning.

It is noteworthy that this method of thermal calculation allows us to accurately calculate a large number of quantities that specifically describe the future heating system. As a result of thermal calculation, the following information will be available:

number of heat losses, boiler output;
number and type of heat radiators for each room separately;
hydraulic characteristics of the pipeline;
volume, velocity of the heat carrier, power of the pump.

Thermal calculation is not theoretical sketches, but quite accurate and well-grounded results, which are recommended to be used in practice when selecting components of the heating system.

Room temperature conditions

Before carrying out any calculations of the parameters of the system, it is necessary, at a minimum, to know the order of the expected results, and also to have standardized characteristics of some tabulated values that must be substituted into formulas or oriented to them. After calculating the parameters with such constants, one can be sure of the reliability of the desired dynamic or constant parameter of the system.

For premises of various purposes, there are standard standards for temperature regimes for residential and non-residential premises. These norms are fixed in the so-called GOSTs

For a heating system, one of such global parameters is the room temperature, which should be constant regardless of the year and environmental conditions.

According to the regulations of sanitary regulations and rules there is a difference in temperature relative to the summer and winter period of the year. For the temperature regime of the room during the summer season, the air conditioning system is responsible, but the room temperature in the winter is provided by the heating system. I mean, we are interested in the temperature ranges and their tolerances for the winter season.

Most regulatory documents specify the following temperature ranges, which allow a person to be comfortable in the room. For non-residential premises of office type with an area of up to 100 m 2:

optimum air temperature 22-24 ° С
permissible fluctuation 1 ° С

For offices of office type with an area of more than 100 m 2, the temperature is 21-23 ° C. For non-residential premises of industrial type, the temperature ranges vary greatly depending on the intended use of the premises and the established occupational safety standards.

Comfortable room temperature for each person "own". Someone likes to be very warm in the room, someone is comfortable when the room is cool - it's all quite individual

As for living quarters: apartments, private houses, estates, etc., there are certain temperature ranges that can be adjusted depending on the wishes of the tenants. And yet for specific premises of an apartment and a house we have:

residential, including children's room, room 20-22 ° С, tolerance ± 2 ° С
kitchen, toilet 19-21 ° С, tolerance ± 2 ° С
bathroom, shower room, swimming pool 24-26 ° С, tolerance ± 1 ° С
corridors, hallways, staircases, storerooms 16-18 ° С, tolerance + 3 ° С

It is important to note that there are several basic parameters that influence the temperature in the room and which need to be oriented when calculating the heating system: humidity (40-60%), oxygen and carbon dioxide concentration in the air (250: 1), air movement speed masses (0.13-0.25 m / s), and so on.

Calculation of heat loss in the house

According to the second law of thermodynamics (school physics) there is no spontaneous transfer of energy from less heated to more heated mini- or macro-objects. A particular case of this law is the "striving" to create a temperature equilibrium between two thermodynamic systems.

For example, the first system is an environment with a temperature of -20 ° C, the second system is a building with an internal temperature of + 20 ° C. According to the law, these two systems will seek to balance themselves through the exchange of energy. This will occur with the help of heat losses from the second system and cooling in the first.

It can be unequivocally said that the ambient temperature depends on the latitude on which the a private house. And the temperature difference affects the amount of heat leakage from the building

By heat loss means the involuntary release of heat (energy) from some object (home, apartment). For an ordinary apartment, this process is not so "noticeable" in comparison with a private house, since the apartment is located inside the building and "neighbors" with other apartments. In a private house, through the external walls, the floor, the roof, the windows and the doors, heat "goes away" to some extent.

Knowing the amount of heat losses for the most unfavorable weather conditions and the characteristics of these conditions, it is possible to calculate the power of the heating system with high accuracy.

So, the amount of heat leakage from the building is calculated by the following formula:

Q = Q Floor + Q Wall + Q Window + Q Roof + Q Door + ... + Q i

where Qi is the volume of heat loss from a homogeneous shell shell. Each component of the formula is calculated by the formula:

Q = S * ΔT / R

where Q is the thermal leakage (Watts), S is the area of a particular type of construction (m 2), ΔT is the difference between ambient air temperature and indoor temperature (° C), R is the thermal resistance of a certain type of construction (m 2 * ° C / W).

The very value of thermal resistance for real materials is recommended to be taken from auxiliary tables. In addition, the thermal resistance can be obtained by the following relationship:

R = d / k

where R is the thermal resistance ((m 2 * K) / W), k is the thermal conductivity of the material (W / (m 2 * K)), d is the thickness of this material (m).

In old houses with a damp roof construction, heat leakage occurs through the upper part of the building, namely through the roof and attic. If you insulate the attic space and the roof, then the total heat loss from the house can be significantly reduced

In the house there are several more types of heat losses through the cracks in the structures, ventilation system, kitchen hood, opening windows and doors. But to take into account their volume does not make sense, since they make up no more than 5% of the total number of major heat losses.

Determination of boiler output

To maintain the temperature difference between the environment and the temperature inside the house, an autonomous heating system is needed, which maintains the desired temperature in each room of the private house.

The basis of the heating system is a boiler: liquid or solid fuel, electric or gas - at this stage it does not matter. The boiler is the central node of the heating system, which generates heat. The main characteristic of the boiler is its power, namely the rate of conversion of the amount of heat per unit of time.

After calculating the heat load for the heating, we obtain the required rated output of the boiler. For a typical multi-room apartment, the boiler output is calculated through the area and specific power:

Р boiler = (S rooms * Р specific) / 10

where S rooms - the total area of the heated room, R - specific power relative to climatic conditions. But this formula does not take into account the heat losses that are sufficient in a private house. There is another relation that takes into account this parameter:

P boiler = (Q losses * S) / 100

where P boiler - boiler power (W), Q losses - heat loss, S - heated area (m 2).

In most private house heating systems, it is recommended to use an expansion tank in which the coolant supply will be stored. Each private house needs hot water supply

In order to provide the reserve capacity of the boiler, taking into account the heating of the water for the kitchen and the bathroom, it is necessary to add the safety factor K to the last formula:

P of the boiler = (Q losses * S * K) / 100

where K - will be equal to 1.25, that is, the design capacity of the boiler will be increased by 25%. Thus, the boiler's capacity makes it possible to maintain the standard air temperature in the building's rooms, as well as to have an initial and additional volume hot water in home.

Features of selection of radiators

The standard components for providing heat in the room are radiators, panels, "warm" floor systems, convectors, etc. The most common parts of the heating system are radiators.

The heat radiator is a special hollow construction of a modular type made of an alloy with a high heat output. It is made of steel, aluminum, cast iron, ceramics and other alloys. The principle of the radiator is reduced to the emission of energy from the coolant into the space of the room through the "petals".

Aluminum and bimetallic radiator has replaced massive cast-iron batteries. The simplicity of production, high heat dissipation, successful design and design have made this product a popular and widespread tool for radiating heat in a room

There are several methods for calculating the number of radiator sections in the room. The following list of methods is sorted in order of increasing the accuracy of the calculation.

By area. N = (S * 100) / C, where N is the number of sections, S is the area of the room (m 2), C is the heat transfer of one section of the radiator (W, taken from those passports or the product certificate), 100 W is the amount of heat flow , which is necessary for heating 1 m 2 (empirical value). The question arises: how to take into account the height of the ceiling of the room?
By volume. N = (S * H * 41) / C, where N, S, C are similar. H - room height, 41 W - the amount of heat flow, which is necessary for heating 1 m 3 (empirical value).
By the coefficients. N = (100 * S * k1 * k2 * k3 * k4 * k5 * k6 * k7) / C, where N, S, C and 100 are similar. k1 - the number of cells in the double-glazed windows of the room window, k2 - the thermal insulation of the walls, k3 - the ratio of the area of windows to the area of the room, k4 - the average minus temperature in the coldest week of winter, k5 - the number of exterior walls of the room (which "go" to the street) k6 - type of premise on top, k7 - ceiling height.

This is the most accurate version of the calculation of the number of sections. Naturally, rounding of fractional results of calculations is always made to the next integer.

Hydraulic calculation of water supply

Of course, the "picture" of calculating heat for heating can not be complete without calculating characteristics such as volume and velocity of the coolant. In most cases, ordinary water in a liquid or gaseous state is the coolant.

The actual volume of the coolant is recommended to be calculated by summing all the cavities in the heating system. When using a single-circuit boiler - this the best option. When using double-circuit boilers in a heating system, it is necessary to take into account the costs of hot water for hygienic and other household purposes

Calculation of the volume of water heated by a double-circuit boiler to provide occupants hot water and heating of the coolant, is made by summing the internal volume of the heating circuit and the actual needs of users in heated water.

The volume of hot water in the heating system is calculated by the formula:

W = k * P

where W is the volume of the heat carrier, P is the capacity of the heating boiler, k is the power factor (the number of liters per unit of power is 13.5, the range is from 10 to 15 liters). As a result, the final formula looks like this:

W = 13.5 * P

The velocity of the heat carrier is the final dynamic evaluation of the heating system, which characterizes the rate of circulation of the liquid in the system. This value helps to evaluate the type and diameter of the pipeline:

V = (0.86 * P * μ) / ΔT

where P is the boiler output, μ is the boiler efficiency, ΔT is the temperature difference between the water supplied and the water return circuit.

Summarizing the above methods of calculating the characteristics, in the end, real results of calculations will be available, which are the "foundation" of the future heating system.

Example of heat calculation

As an example of heat calculation, there is a usual one-storey house with four living rooms, a kitchen, a bathroom, a "winter garden" and utility rooms.

The foundation is made of a monolithic reinforced concrete slab (20 cm), the outer walls are concrete (25 cm) with plaster, the roof is covered with wooden beams, the roof is made of metal and mineral wool (10 cm)

Dimensions of the building. The height of the floor is 3 meters. Small window of the front and rear part of the building 1470 * 1420 mm, large facade window 2080 * 1420 mm, entrance doors 2000 * 900 mm, rear door (exit to the terrace) 2000 * 1400 (700 + 700) mm.

The total width of the building is 9.5 m 2, the length is 16 m 2. Only residential rooms (4 pcs.), A bathroom and a kitchen will be heated. To accurately calculate heat losses on walls from the area of external walls, you need to subtract the area of all windows and doors - this is a completely different type of material with its thermal resistance

We start with the calculation of areas of homogeneous materials:

floor area 152 m 2
roof area 180 m 2 (considering the height of the attic of 1.3 meters and the width of the run - 4 meters)
the area of windows 3 * 1.47 * 1.42 + 2.08 * 1.42 = 9.22 m 2
the area of the doors will be 2 * 0.9 + 2 * 2 * 1.4 = 7.4 m 2

The area of the outer walls will be 51 * 3-9.22-7.4 = 136.38 m 2. Let's proceed to the calculation of heat loss on each material:

Q floor = S * ΔT * k / d = 152 * 20 * 0.2 / 1.7 = 357.65 W
Q roof = 180 * 40 * 0.1 / 0.05 = 14400 W
Q window = 9.22 * 40 * 0.36 / 0.5 = 265.54 W
Q doors = 7.4 * 40 * 0.15 / 0.75 = 59.2 W

And also Q wall is equivalent to 136.38 * 40 * 0.25 / 0.3 = 4546. The sum of all heat losses will be 19628.4 W. As a result, we calculate the boiler output:

P boiler = Q loss * S heating room * K / 100 =
19628.4 * (10.4 + 10.4 + 13.5 + 27.9 + 14.1 + 7.4) * 1.25 / 100 = 19628.4 * 83.7 * 1.25 / 100 = 20536.2 = 21 kW

Calculate the number of radiator sections for one of the rooms. For all others, the calculations are similar. For example, the corner room (on the left, the bottom corner of the scheme) is 10.4 m2.

N = (100 * k1 * k2 * k3 * k4 * k5 * k6 * k7) / C = (100 * 10.4 * 1.0 * 1.0 * 0.9 * 1.3 * 1.2 * 1.0 * 1.05) /180=8.5176=9

For this room you need 9 sections of a radiator with 180 W heat dissipation. Let's pass to the calculation of the amount of coolant in the system:

W = 13.5 * P = 13.5 * 21 = 283.5 liters

The velocity of the coolant will be:

V = (0.86 * P * μ) / ΔT = (0.86 * 21000 * 0.9) /20 = 812.7 liters

As a result, the total turnover of the entire volume of the coolant in the system will be equivalent to 2.87 times in one hour.

Video materials for the calculation of heating

A simple calculation of the heating system for a private house is presented in the following overview:

All the subtleties and common methods for calculating the heat loss of the building are shown below:

Another option for calculating heat leakage in a typical private house:

This video tells about the features of the energy carrier circulation for heating the home:

Thermal calculation of the heating system is individual, it must be done correctly and accurately. The more accurately the calculations are made, the less the overpayers will have to the owners a country house in the process of operation.

It is clear that in the peak of winter frosts I do not want to face a lack of heat; it is equally unpleasant to throw out money, having overpaid for the equipment unnecessary to you. So, let's start counting.

Our goal is to provide the house with warmth. If possible, with minimal costs.

What to expect

We decompose the big problem into components. We have to choose:

The thermal power of the heat source is an autonomous heating boiler. It should with a minimum reserve provide the house with warmth in the coldest weeks of winter.
Number and size of heating appliances. As a rule - the number of sections of radiators, although, of course, along with them, convectors or registers can be used.
Diameter of pipes to be transported.

In this order and proceed to the calculations.

Boiler

general information

In the beginning - a little general information about the types of fuel.

In terms of current operating costs, the cheapest type of fuel is the main gas. In terms of economy the best choice - condensing boilers using higher heat of combustion by condensation of gas combustion products. However, it is easy to predict that in the coming years natural gas will rise in price: its reserves are limited, and demand is growing.
The next most economical energy sources are firewood and coal. The general problem of solid fuel boilers is the need for maintenance: at least twice a day the boiler needs to be heated. However, the heat accumulator will make ignition more rare.

Attention: for coal and firewood thermal power varies by about 10 percent in favor of coal. Calculation of house heating should be based on power when using the type of fuel that is relevant for you.

The only reasonable way to use electricity for heating is heat pumps of different types. At them electric and effective thermal capacity differ in 3-6 times. The efficiency of air-to-air pumps falls as the street temperature decreases, which also needs to be taken into account in the calculations.

The photo shows an air-to-air heat pump. These devices are cheaper working on other schemes; but at negative temperatures, their effectiveness decreases.

Calculation of heat output

The first and simplest way is laid in SNiP: for heating the house requires one kilowatt of heat for every 10 m2 of area. For a house with an area of 100 m2, a ten-kilowatt boiler is needed.

The instruction is extremely simple, accessible and ... gives huge errors.

The volume of air at a ceiling height of 2.4 and 4.5 meters will be, to put it mildly, different. And warm air will inevitably be collected under the ceiling.
The heat leakage through the walls and the ceiling is the higher, the more delta temperatures with the street. In Oymyakon the house will be cooled much more intensively than in Gelendzhik.
Windows and doors for heat permeability are very different from walls.
In addition, the calculation is strongly influenced by whether it is a private house or apartment. SNiP piles all the calculations into one pile; Meanwhile, heat leakage in a private house will be much greater than in a multi-apartment building. After all, from below and from above he does not have warm neighbors' rooms, but a street.

For one cubic meter of the volume of the heated room, 40 watts of thermal power is taken.
Each window adds to the heat demand of 100 watts. Each door is 200.
For a private house, a coefficient of 1.5 is used - precisely because in his case all the walls along the perimeter are common with the street. AT apartment house for corner and end apartments a coefficient of 1.2-1.3 is taken, depending on the thickness and material of the walls.
The correction for the region with its climate varies from 0.7 for the southern regions of Russia to 2.0 for Yakutia and Chukotka. The Moscow and Leningrad regions use a regional coefficient of 1.2.

Let's take as an example the need to heat one floor of a private house measuring 12x6.5 meters, with ceilings of 3.2 meters high, four windows and two doors, located on the Black Sea coast.

The area is 12 * 6.5 = 78 m2. The volume is 78 * 3.2 = 249.6 m3. The basic value of the thermal power is 249.6 * 40 = 9984 watts.

4 windows will add 400 watts, two doors - the same number. 9984 + 400 + 400 = 10784.

A private house. The coefficient of 1.5 will give us 16,176 watts.

The extremely warm climate of the sea coast with the positive temperature of the coldest month will force us to multiply the obtained value by 0.7. 16176 * 0.7 = 11323 watts. Therefore, we have a small enough supply of a boiler with an effective heat output of 12 kilowatts.

Curiously, in practice, for heating this floor, there are enough two air conditioners with half the total heat output, most of the time one of them works. Affect good insulation and adjacent to the neighboring houses walls. As you can see, even this formula gives very approximate data.

Heating devices

So, we are going to create a heating system with our own hands, and we select radiators for it. How many sections do we need for each room?

It will be necessary to start from the heat capacity necessary for each room. The same calculation technique is used as for the whole house. After we find out the need for a room in the warmth - it will only be necessary to select the appropriate heating device for it.

Where can you get data on how much heat radiates a radiator, convector or fan coil?

The technical passport of the product from a fairly decent manufacturer contains this information.

Nuance: manufacturers indicate the heat flow for the delta of temperatures between the room and the heating device at 70 degrees. That is, for example, at 20 ° C in a room, the battery should be heated to 90 ° C. You understand that the real values can be very different.

For sectional radiators of all types, the power of the section can be found on the developer's website. Next - a simple arithmetic calculation.

We present the averaged data for sections of different types with a standard (500 millimeters) interaxial distance between the connections.

Cast iron section gives about 140 watts of heat. Recall, in the delta of temperatures with a room of 70 degrees.
The heat transfer of the bimetallic section is about 180 watts.
A fully aluminum battery is capable of delivering about 190-210 watts per section. Given that the price of the aluminum section rarely exceeds 300 rubles, and the strength is more than sufficient for an autonomous heating system, the popularity of this type of heating devices among private house owners is understandable.

Pipes

Practice

For the gravity system, the filling is mounted with a pipe of a highly overstated section - not less than DN32. The goal is to minimize the hydraulic resistance with a minimal difference in the circuit. More often used pipes DU40 - DU50. Radiators do not break the contour, but are mounted parallel to it; The piping is made by a pipe DN20 mm.

Attention: do not confuse the DN of the pipe with its outer diameter. Polypropylene Pipe with a clearance corresponding to 32 millimeters, will have an outer diameter of about 40 mm.

In the case of systems with forced circulation A polypropylene, polyethylene or metal-plastic pipe with an external diameter of 25 millimeters is taken. With a reasonable area of the house this diameter is more than enough.
When beam distribution The feeder feeds only one heater. Take a plastic or cross-linked polyethylene with a diameter of 16 millimeters.

Calculations

If you still want to conduct a technically correct calculation of the heating system at home with the calculation of the minimum cross-section of pipes - it is worth using the table.

The optimum velocity of the coolant flow is about 0.6 m / s. The maximum is 1.5. At higher speed, noise will appear in the circuit.

How to use it?

Suppose that we need to ensure transportation of a heat carrier with a heat flux of 12 kilowatts. The value is quite real at the output of a low-power boiler. The optimal speed of water movement is 0.6 meters per second.

We are looking for the speed in the upper row and go down the table until the upper line shows the value of the heat flux ABOVE necessary to us. Rounding the values here is only in the larger side.

As it is easy to see, we need an INNER diameter of 20 millimeters, which for polypropylene corresponds to an external diameter of 25 mm.

Conclusion

Some additional information on the calculation methods of heating systems can be found in the video attached to the article. Warm winters!

The system of water heating has been increasingly popular recently as the main way for heating a private house. Water heating can be supplemented with devices such as heaters that work on electricity. Some devices and heating systems appeared on the domestic market quite recently, but already managed to gain popularity. These include infrared heaters, oil coolers, a warm floor system and others. To heat a local type, a device such as a fireplace is often used.

However, recently fireplaces perform more decorative function than heating. On how well the design and calculation of private house heating has been carried out, and the water heating system has been installed, its durability and efficiency during operation depend. During the operation of such a heating system, it is necessary to adhere to certain rules so that it works as efficiently and efficiently as possible.

The heating system of a private house is not only components such as a boiler or radiators. A water-type heating system includes such elements as:

Pumps;
Means of automation;
Pipeline;
Heat carrier;
Devices for adjustment.

To calculate the heating of a private house, you need to be guided by such parameters as the capacity of the boiler. For each of the rooms in the house, it is also necessary to calculate the power of the radiators.

Boiler selection

The boiler can be of several types:

A boiler operating on liquid fuel;
A gas boiler;
Solid fuel boiler;
Combined boiler.

The choice of a boiler that will use the heating scheme of a residential house should depend on which type of fuel is the most affordable and inexpensive.

In addition to the cost of fuel, it is required at least once a year to conduct a preventive inspection of the boiler. It is best for these purposes to call a specialist. Also, you need to perform preventive cleaning of filters. The most simple to operate are boilers that operate on gas. They are also quite cheap in maintenance and repair. The gas boiler will only fit in those houses that have access to the gas main.

Gas is a type of fuel that does not require individual transportation or storage space. In addition to this, many gas boilers modern type can boast a fairly high efficiency.

Boilers of this class are distinguished by a high degree of safety. Modern boilers are designed in such a way that they do not need to allocate a special room for the boiler house. Modern boilers are characterized by a beautiful appearance and are able to successfully fit into the interior of any kitchen.

To date, semi-automatic boilers operating on solid fuel are very popular. True, there is one disadvantage of such boilers, which is that once a day you need to load fuel. Many manufacturers produce such boilers that are fully automated. In such boilers solid fuel is loaded in an autonomous mode.

Make a calculation of the heating system of a private house is possible in the case of a boiler operating on electricity.

However, such boilers are a bit more problematic. In addition to the main problem, which is that now electricity is quite expensive, they can still reboot the network. In small settlements, an average of 3 kW per hour is allocated per house, and this is not enough for a boiler, and it should be borne in mind that the network will be loaded not only by the operation of the boiler.

For the organization of the heating system of a private house, it is possible to install a liquid-fuel type boiler. The disadvantage of such boilers is that they can cause criticism in terms of ecology and safety.

Calculation of boiler power

Before calculating the heating in the house, it is necessary to do this with the calculation of the boiler output. The efficiency of the entire heating system will depend on the boiler's capacity, first of all. The main thing in this matter is not to overdo it, since a too powerful boiler will consume more fuel than necessary. And if the boiler is too weak, it will not be possible to heat the house properly, and this will negatively affect the comfort in the house. Therefore, the calculation of the heating system of a country house is important. To choose a boiler of the necessary capacity it is possible, if in parallel to calculate the specific heat losses of the building for the entire heating period. Calculation of home heating - specific heat loss can be the following method:

q house = Q year / F h

Qgod is the heat energy consumption for the entire heating period;

Fh is the area of the house that is heated;

In order to calculate the heating of a country house - the energy consumption that will leave the heating of a private house, you need to use the following formula and a tool such as a calculator:

Q year = β h *

In the video, the procedure for calculating heat losses at home through enclosing structures is considered. Knowing the heat loss, it will be possible to accurately calculate the capacity of the heating system:

The choice of capacity of the boiler depends on the condition of the house and the quality of insulation of its enclosing structures. The principle of "kilowatt per 10 squares of area" works in a cottage of average condition of facades, roof and foundation. A detailed video on the principles of selecting the power characteristics of a heating boiler see below:

The production of heat annually becomes more expensive - the prices for fuel are rising. You can not treat the energy costs of the cottage indifferently, it is completely unprofitable. On the one hand, each new heating season costs the homeowner more expensive and more expensive. On the other hand, the warming of the walls, the foundation and the roof of a suburban one costs good money. However, the less heat leaves the building, the cheaper it will be to heat it.

Of all the currently known options for heating your home, the most common type is individual system water heating. Oil radiators, fireplaces, stoves, fan heaters and infrared heaters are often used as auxiliary devices.

The heating system of a private house consists of heating appliances, a pipeline and shut-off and regulating mechanisms, all of this serves to transport heat from the heat generator to the final points of space heating. It is important to understand that the reliability, durability and efficiency of an individual heating system depends on its correct calculation and installation, as well as on the quality of the materials used in this system and its competent operation.

Calculation of the heating system

Let's consider in detail the simplified version of the calculation of the water heating system, in which we will use standard and public components. The figure shows schematically the individual heating system of a private house on the basis of a single-circuit boiler. First of all, we need to determine its power, as it is the basis of all calculations in the future. We will perform this procedure as described below.

Total area of the room: S = 78.5; total volume: V = 220

We have a one-storey house with three rooms, an entrance hall, a corridor, a kitchen, a bathroom and a toilet. Knowing the area of each individual room and the height of the rooms, it is necessary to perform elementary calculations in order to calculate the volume of the whole house:

room 1: 10 m 2 · 2.8 m = 28 m 3
room 2: 10 m 2 · 2.8 m = 28 m 3
room 3: 20 m 2 · 2.8 m = 56 m 3
entrance hall: 8 m 2 · 2.8 m = 22.4 m 3
corridor: 8 m 2 · 2.8 m = 22.4 m 3
kitchen: 15.5 m 2 · 2.8 m = 43.4 m 3
bathroom: 4 m 2 · 2.8 m = 11.2 m 3
wC: 3 m 2 · 2.8 m = 8.4 m 3

Thus, we have calculated the volume of all individual rooms, thanks to which we can now calculate the total volume of the house, it is equal to 220 cubic meters. Notice, we also calculated the volume of the corridor, but in fact there is not indicated a single heater, what is it for? The fact is that the corridor will also be heated, but passively, due to the circulation of heat, so we need to make it into the general list of heating, in order for the calculation to be correct and give the desired result.

The next step in calculating the boiler output will be carried out based on the required quantity energy per one cubic meter. For each region there is an indicator - in our calculations we use 40 W per cubic meter, based on recommendations for the regions of the European part of the CIS:

40 W · 220 m 3 = 8800 W

The resulting figure needs to be raised to a factor of 1.2, which will give us a 20% power reserve to ensure that the boiler does not constantly work at full capacity. Thus, we understand that we need a boiler that is capable of producing 10.6 kW (standard single-circuit boilers are produced with a capacity of 12-14 kW).

Calculation of radiators

In our case, we will use standard aluminum radiators with a height of 0.6 m. The power of each rib of such a radiator at a temperature of 70 ° C is 150 W. Next, we calculate the power of each radiator and the number of conditional edges:

room 1: 28 m 3 · 40 W · 1,2 = 1344 W. We round up to 1500 and get 10 conditional edges, but since we have two radiators, both under the windows, we take one with 6 ribs, the second with 4.
room 2: 28 m 3 · 40 W · 1,2 = 1344 Tues. We round up to 1500 and get one radiator with 10 ribs.
room 3: 56 m 3 · 40 W · 1,2 = 2688 Tues We round up to 2700 and get three radiators: the 1st and the 2nd on the 5 edges, the 3rd (the side) - the 8 edges.
hall: 22.4 m 3 · 40 W · 1.2 = 1075.2 W. We round up to 1200 and get two radiators with 4 ribs.
bathroom: 11,2 m 3 · 45 W · 1,2 = 600 W. Here the temperature should be a little higher, you get 1 radiator with 4 ribs.
wC: 8.4 m 3 · 40 W · 1.2 = 403.2 W. We round up to 450 and get three edges.
kitchen: 43.4 m 3 · 40 W · 1.2 = 2083.2 W. We round up to 2100 and get two radiators of 7 edges.

In the end result, we see that we need 12 radiators with a total capacity:

900 + 600 + 1500 + 750 + 750 + 1200 + 600 + 600 + 600 + 450 + 1050 + 1050 = 10.05 kW

Based on recent calculations, it is clear that our individual heating system will cope with the load imposed on it without problems.

Pipe Selection

Pipeline for the system individual heating is the environment for transportation of thermal energy (in particular, heated water). In the domestic market, pipes for installation of systems are presented in three main types:

metal
copper
plastic

Metal pipes have a number of significant disadvantages. In addition, they have a high weight and require special equipment for installation, as well as experience, they are still prone to corrosion and can accumulate static electricity. A good option - copper pipes, they are able to withstand temperatures of up to 200 degrees and pressures of about 200 atmospheres. But copper pipes are different in the installation (requires special equipment, silver solder and extensive experience), in addition, their cost is very high. The most popular option is plastic pipes. And that's why:

they have an aluminum base, which is covered with plastic on both sides, so that they have great strength;
they absolutely do not pass oxygen, which allows to reduce the process of corrosion formation on internal walls to zero;
thanks to the aluminum reinforcement they have a very low coefficient of linear expansion;
plastic pipes are antistatic;
have low hydraulic resistance;
no special skills are required for installation.

Installation of the system

First of all, we need to install sectional radiators. They should be placed strictly under the windows, warm air from the radiator will prevent the penetration of cold air from the window. For the installation of sectional radiators, no special equipment will be required, only a puncher and a building level. It is necessary to strictly adhere to one rule: all radiators in the house must be mounted strictly at one horizontal level, this depends on the general circulation of water in the system. Also observe the vertical position of the fins of the radiator.

After installing the radiators, you can start laying the pipes. It is necessary to measure in advance the total length of the pipes, and also to calculate the number of all kinds of fittings (elbows, tees, plugs, etc.). For installation of plastic pipes Only three tools are needed - roulette, pipe scissors and a soldering iron. Most of these pipes and fittings have laser perforation in the form of incisions and guide lines, which makes it possible in the place to perform the installation correctly and smoothly. When working with a soldering iron, you should adhere to only one rule - after you have melted and docked the ends of the products, do not scroll them, if at first you can not solder it smoothly, otherwise it is possible to flow in this place. It is better to practice in advance on the pieces that will go to waste.

Additional devices

According to statistics, a system with passive water circulation will function properly if the area of the room does not exceed 100-120 m 2. Otherwise it is necessary to use special pumps. Of course, there are a number of boilers in which pumping systems are already integrated and they themselves ensure the circulation of water through pipes, if you do not have one, you should purchase it separately.

In the domestic market, their choice is very large, besides they meet all the necessary requirements - they consume little electricity, are quiet and small. Mount circulating pumps on the ends of heating branches. Thus, the pump will last longer, as it will not be exposed to direct hot water.

Example single-pipe system heating with forced circulation: 1 - boiler; 2 - security group; 3 - radiators of heating; 4 - needle valve; 5 - expansion tank; 6 - drain; 7 - water supply; 8 - filter coarse cleaning water; 9 - circulation pump; 10 - ball valves

From all of the above, it becomes clear that with the installation of such a system can easily cope with two or three people, it does not need to have special professional skills, most importantly, be able to use basic construction tools. In our article, we examined the system of individual heating, assembled with standard components, their price and accessibility will allow almost everyone at home to mount a similar heating system.