Thermal calculation of a heating system: how to correctly calculate the load on the system. Calculation of heating by room area Design heating load formula

When equipping a building with a heating system, you need to take into account a lot of points, starting from quality Supplies and functional equipment and ending with calculations of the required node power. So, for example, you will need to calculate the heat load for heating a building, a calculator for which will be very useful. It is carried out using several methods, which take into account a huge number of nuances. Therefore, we invite you to take a closer look at this issue.

Average indicators as the basis for calculating the heat load

In order to correctly calculate the heating of a room based on the volume of coolant, the following data must be determined:

the amount of fuel required;
heating unit performance;
efficiency of the specified type of fuel resource.

In order to eliminate cumbersome calculation formulas, specialists from housing and communal services enterprises have developed a unique methodology and program with which you can literally calculate the thermal load for heating and other data required when designing a heating unit in just a matter of minutes. Moreover, using this technique, you can correctly determine the cubic capacity of the coolant for heating a particular room, regardless of the type of fuel resource.

Basics and features of the technique

A technique of this kind, which can be used using a calculator for calculating heat energy for heating a building, is very often used by employees of cadastral companies to determine the economic and technological efficiency of various programs aimed at energy saving. In addition, with the help of similar computational techniques, new functional equipment is introduced into projects and energy-efficient processes are launched.

So, to calculate the heat load for heating a building, experts use the following formula:

a - coefficient that shows difference adjustments temperature regime external air when determining the efficiency of the heating system;
t i,t 0 - temperature difference indoors and outdoors;
q 0 - specific exponent, which is determined by additional calculations;
K u.p - infiltration coefficient, taking into account all kinds of heat loss, ranging from weather conditions to the absence of a heat-insulating layer;
V is the volume of the structure that needs heating.

How to calculate the volume of a room in cubic meters (m3)

The formula is very primitive: you just need to multiply the length, width and height of the room. However, this option is only suitable for determining the cubic capacity of a structure that has a square or rectangular shape. In other cases, this value is determined in a slightly different way.

If the premises is a room irregular shape, then the task becomes somewhat more complicated. In this case, you need to divide the area of the rooms into simple figures and determine the cubic capacity of each of them, having made all measurements in advance. All that remains is to add up the resulting numbers. Calculations should be carried out in the same units of measurement, for example, in meters.

If the structure for which a large-scale calculation of the building’s thermal load is being made is equipped with an attic, then the cubic capacity is determined by multiplying the indicator of the horizontal section of the house (we are talking about an indicator that is taken from the level of the floor surface of the first floor) by its full height, taking into account the highest point of the attic insulation layer.

Before calculating the volume of the room, it is necessary to take into account the fact of the presence ground floors or basements. They also need heating and, if any, then another 40% of the area of these rooms should be added to the cubic capacity of the house.

To determine the infiltration coefficient, K u.p, you can use the following formula as a basis:

where is the root of the total cubic capacity of the premises in the building, and n is the number of rooms in the building.

Possible energy losses

To make the calculation as accurate as possible, you need to take into account absolutely all types of energy losses. So, the main ones include:

through the attic and roof, if they are not properly insulated, the heating unit loses up to 30% of heat energy;
if available in the house natural ventilation(chimney, regular ventilation etc.) up to 25% of heat energy is consumed;
If the wall ceilings and floor surfaces are not insulated, then up to 15% of energy can be lost through them, the same amount goes through the windows.

How more windows And doorways in housing, the greater the heat loss. If the thermal insulation of a house is of poor quality, on average, up to 60% of the heat escapes through the floor, ceiling and facade. The largest heat-transfer surface is the window and facade. The first step is to replace the windows in the house, after which they begin to insulate it.

Considering possible energy losses, you need to either eliminate them by resorting to thermal insulation material, or add their value when determining the volume of heat for heating the room.

As for the arrangement of stone houses, the construction of which has already been completed, it is necessary to take into account higher heat losses at the beginning of the heating period. In this case, it is necessary to take into account the completion date of construction:

from May to June - 14%;
September - 25%;
from October to April - 30%.

Hot water supply

The next step is to calculate the average hot water load in heating season. For this, the following formula is used:

a - average daily use rate hot water(this value is standardized and can be found in the SNiP table, Appendix 3);
N is the number of residents, employees, students or children (if we are talking about preschool institution) under construction;
t_c is the value of water temperature (measured in fact or taken from average reference data);
T - time period during which hot water is supplied (if we are talking about hourly water supply);
Q_(t.n) - heat loss coefficient in the hot water supply system.

Is it possible to regulate the loads in the heating unit?

Just a few decades ago this was an unrealistic task. Today, almost all modern heating boilers of industrial and household use are equipped with thermal load regulators (RTN). Thanks to such devices, the power of heating units is maintained at a given level, and surges and passes during their operation are eliminated.

Heat load regulators make it possible to reduce financial costs for paying for the consumption of energy resources for heating a structure.

This is due to a fixed power limit of the equipment, which, regardless of its operation, does not change. This is especially true for industrial enterprises.

Making a project on your own and calculating the load of heating units that provide heating, ventilation and air conditioning in a building is not so difficult, the main thing is to be patient and have the necessary knowledge.

VIDEO: Calculation of heating batteries. Rules and errors

In houses that were commissioned in last years, usually these rules are met, so the calculation heating power equipment is based on standard coefficients. Individual calculations can be carried out at the initiative of the homeowner or the utility structure involved in the supply of heat. This happens when spontaneous replacement of heating radiators, windows and other parameters occurs.

In an apartment served by a utility company, the calculation of the heat load can only be carried out upon transfer of the house in order to track the SNIP parameters in the premises accepted for balance. Otherwise, the apartment owner does this in order to calculate his heat loss in the cold season and eliminate the shortcomings of insulation - use heat-insulating plaster, glue the insulation, install penofol on the ceilings and install metal-plastic windows with a five-chamber profile.

Calculating heat leaks for a utility for the purpose of opening a dispute, as a rule, does not yield results. The reason is that there are heat loss standards. If the house is put into operation, then the requirements are met. At the same time, heating devices comply with the requirements of SNIP. Battery replacement and selection more heat is prohibited, as radiators are installed according to approved building standards.

Private houses are heated autonomous systems, that in this case the load calculation is carried out to comply with SNIP requirements, and heating power adjustments are carried out in conjunction with work to reduce heat loss.

Calculations can be done manually using a simple formula or a calculator on the website. The program helps to calculate required power heating systems and heat leaks characteristic of the winter period. Calculations are carried out for a specific thermal zone.

Basic principles

The methodology includes a number of indicators that together make it possible to assess the level of insulation of a house, compliance with SNIP standards, as well as the power of the heating boiler. How it works:

An individual or average calculation is carried out for the object. The main point of conducting such a survey is that when good insulation and small heat leaks in winter, you can use 3 kW. In a building of the same area, but without insulation, at low winter temperatures the power consumption will be up to 12 kW. Thus, thermal power and load are assessed not only by area, but also by heat loss.

The main heat losses of a private house:

windows – 10-55%;
walls – 20-25%;
chimney – up to 25%;
roof and ceiling – up to 30%;
low floors – 7-10%;
temperature bridge in the corners – up to 10%

These indicators can vary for better and worse. They are evaluated depending on the types installed windows, thickness of walls and materials, degree of ceiling insulation. For example, in poorly insulated buildings, heat loss through the walls can reach 45% percent; in this case, the expression “we are drowning the street” is applicable to the heating system. Methodology and
The calculator will help you estimate nominal and calculated values.

Specifics of calculations

This technique can also be found under the name “thermal engineering calculation”. The simplified formula is as follows:

Qt = V × ∆T × K / 860, where

V – room volume, m³;

∆T – maximum difference indoors and outdoors, °C;

K – estimated heat loss coefficient;

860 – conversion factor in kW/hour.

The heat loss coefficient K depends on building structure, thickness and thermal conductivity of walls. For simplified calculations, you can use the following parameters:

K = 3.0-4.0 – without thermal insulation (non-insulated frame or metal structure);
K = 2.0-2.9 – low thermal insulation (masonry in one brick);
K = 1.0-1.9 – average thermal insulation ( brickwork two bricks);
K = 0.6-0.9 – good thermal insulation according to the standard.

These coefficients are averaged and do not allow one to estimate heat loss and heat load on the room, so we recommend using an online calculator.

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Whether it is an industrial building or a residential building, you need to carry out competent calculations and draw up a diagram of the heating system circuit. At this stage, experts recommend paying special attention to calculating the possible thermal load on the heating circuit, as well as the volume of fuel consumed and heat generated.

Thermal load: what is it?

This term refers to the amount of heat given off. A preliminary calculation of the thermal load will allow you to avoid unnecessary costs for the purchase of heating system components and their installation. Also, this calculation will help to correctly distribute the amount of heat generated economically and evenly throughout the building.

There are many nuances involved in these calculations. For example, the material from which the building is built, thermal insulation, region, etc. Experts try to take into account as many factors and characteristics as possible to obtain a more accurate result.

Calculation of heat load with errors and inaccuracies leads to inefficient operation of the heating system. It even happens that you have to redo sections of an already working structure, which inevitably leads to unplanned expenses. And housing and communal services organizations calculate the cost of services based on data on heat load.

Main Factors

An ideally calculated and designed heating system should maintain the set temperature in the room and compensate for the resulting heat losses. When calculating the heat load on the heating system in a building, you need to take into account:

Purpose of the building: residential or industrial.

Characteristics of the structural elements of the building. These are windows, walls, doors, roof and ventilation system.

Dimensions of the home. The larger it is, the more powerful the heating system should be. It is imperative to take into account the area of window openings, doors, external walls and the volume of each internal room.

Availability of rooms special purpose(bath, sauna, etc.).

Degree of equipment with technical devices. That is, the availability of hot water supply, ventilation system, air conditioning and type of heating system.

For a separate room. For example, in rooms intended for storage, it is not necessary to maintain a temperature that is comfortable for humans.

Number of hot water supply points. The more there are, the more the system is loaded.

Area of glazed surfaces. Rooms with French windows lose a significant amount of heat.

Additional terms and conditions. In residential buildings this may be the number of rooms, balconies and loggias and bathrooms. In industrial - the number of working days in a calendar year, shifts, technological chain production process etc.

Climatic conditions of the region. When calculating heat loss, street temperatures are taken into account. If the differences are insignificant, then a small amount of energy will be spent on compensation. While at -40 o C outside the window it will require significant expenses.

Features of existing methods

The parameters included in the calculation of the thermal load are found in SNiPs and GOSTs. They also have special heat transfer coefficients. From the passports of the equipment included in the heating system, digital characteristics relating to a specific heating radiator, boiler, etc. are taken. And also traditionally:

Heat consumption, taken to the maximum per hour of operation of the heating system,

The maximum heat flow emanating from one radiator is

Total heat consumption in a certain period (most often a season); if hourly load calculation is required heating network, then the calculation must be carried out taking into account the temperature difference during the day.

The calculations made are compared with the heat transfer area of the entire system. The indicator turns out to be quite accurate. Some deviations do happen. For example, for industrial buildings it will be necessary to take into account the reduction in thermal energy consumption on weekends and holidays, and in residential premises - at night.

Methods for calculating heating systems have several degrees of accuracy. To reduce the error to a minimum, it is necessary to use rather complex calculations. Less accurate schemes are used if the goal is not to optimize the costs of heating system.

Basic calculation methods

Today, the calculation of the heat load for heating a building can be carried out using one of the following methods.

Three main

For calculations, aggregated indicators are taken.
The indicators of the structural elements of the building are taken as the basis. Here, the calculation of the internal volume of air used for heating will also be important.
All objects included in the heating system are calculated and summed up.

One example

There is also a fourth option. It has a fairly large error, because the indicators taken are very average, or there are not enough of them. This formula is Q from = q 0 * a * V H * (t EN - t NRO), where:

q 0 - specific thermal performance buildings (most often determined by the coldest period),
a - correction factor (depends on the region and is taken from ready-made tables),
V H is the volume calculated along the external planes.

Example of a simple calculation

For a building with standard parameters (ceiling heights, room sizes and good thermal insulation characteristics) you can apply a simple ratio of parameters adjusted for a coefficient depending on the region.

Let's assume that a residential building is located in the Arkhangelsk region, and its area is 170 square meters. m. The heat load will be equal to 17 * 1.6 = 27.2 kW/h.

This definition of thermal loads does not take into account many important factors. For example, design features buildings, temperatures, number of walls, ratio of wall areas to window openings, etc. Therefore, such calculations are not suitable for serious heating system projects.

It depends on the material from which they are made. The most commonly used today are bimetallic, aluminum, steel, much less often cast iron radiators. Each of them has its own heat transfer (thermal power) indicator. Bimetallic radiators with a distance between the axes of 500 mm, on average they have 180 - 190 W. Aluminum radiators have almost the same performance.

The heat transfer of the described radiators is calculated per section. Steel plate radiators are non-separable. Therefore, their heat transfer is determined based on the size of the entire device. For example, thermal power a double-row radiator with a width of 1,100 mm and a height of 200 mm will be 1,010 W, and panel radiator made of steel with a width of 500 mm and a height of 220 mm will amount to 1,644 W.

The calculation of a heating radiator by area includes the following basic parameters:

Ceiling height (standard - 2.7 m),

Thermal power (per sq. m - 100 W),

One external wall.

These calculations show that for every 10 sq. m requires 1,000 W of thermal power. This result is divided by the thermal output of one section. The answer is required amount radiator sections.

For the southern regions of our country, as well as for the northern ones, decreasing and increasing coefficients have been developed.

Average calculation and accurate

Taking into account the described factors, the average calculation is carried out according to the following scheme. If per 1 sq. m requires 100 W of heat flow, then a room of 20 sq. m should receive 2,000 watts. A radiator (popular bimetallic or aluminum) of eight sections produces about Divide 2,000 by 150, we get 13 sections. But this is a rather enlarged calculation of the thermal load.

The exact one looks a little scary. Nothing complicated really. Here's the formula:

Q t = 100 W/m 2 × S(room)m 2 × q 1 × q 2 × q 3 × q 4 × q 5 × q 6 × q 7, Where:

q 1 - type of glazing (regular = 1.27, double = 1.0, triple = 0.85);
q 2 - wall insulation (weak or absent = 1.27, wall laid with 2 bricks = 1.0, modern, high = 0.85);
q 3 - the ratio of the total area of window openings to the floor area (40% = 1.2, 30% = 1.1, 20% - 0.9, 10% = 0.8);
q 4 - outside temperature(the minimum value is taken: -35 o C = 1.5, -25 o C = 1.3, -20 o C = 1.1, -15 o C = 0.9, -10 o C = 0.7);
q 5 - number of external walls in the room (all four = 1.4, three = 1.3, corner room= 1.2, one = 1.2);
q 6 - type of calculation room above the calculation room (cold attic = 1.0, warm attic = 0.9, heated residential room = 0.8);
q 7 - ceiling height (4.5 m = 1.2, 4.0 m = 1.15, 3.5 m = 1.1, 3.0 m = 1.05, 2.5 m = 1.3).

Using any of the described methods, you can calculate the heat load of an apartment building.

Approximate calculation

The conditions are as follows. Minimum temperature in the cold season - -20 o C. Room 25 sq. m with triple glazing, double-glazed windows, ceiling height of 3.0 m, two-brick walls and an unheated attic. The calculation will be as follows:

Q = 100 W/m 2 × 25 m 2 × 0.85 × 1 × 0.8(12%) × 1.1 × 1.2 × 1 × 1.05.

The result, 2,356.20, is divided by 150. As a result, it turns out that 16 sections need to be installed in a room with the specified parameters.

If calculation in gigacalories is required

In the absence of a thermal energy meter on an open heating circuit, the calculation of the heat load for heating the building is calculated using the formula Q = V * (T 1 - T 2) / 1000, where:

V - the amount of water consumed by the heating system, calculated in tons or m 3,
T 1 - a number indicating the temperature of hot water, measured in o C and for calculations the temperature corresponding to a certain pressure in the system is taken. This indicator has its own name - enthalpy. If in practical terms we remove temperature indicators It is not possible, they resort to the average indicator. It is within 60-65 o C.
T 2 - temperature cold water. It is quite difficult to measure it in the system, so constant indicators have been developed that depend on the temperature outside. For example, in one of the regions, in the cold season this indicator is taken equal to 5, in the summer - 15.
1,000 is the coefficient for obtaining the result immediately in gigacalories.

In the case of a closed circuit, the heat load (gcal/hour) is calculated differently:

Q from = α * q o * V * (t in - t n.r.) * (1 + K n.r.) * 0.000001, Where

The calculation of the heat load turns out to be somewhat enlarged, but this is the formula given in the technical literature.

Increasingly, in order to increase the efficiency of the heating system, they are resorting to buildings.

This work is carried out in the dark. For a more accurate result, you need to observe the temperature difference between indoors and outdoors: it should be at least 15 o. Lamps daylighting and the incandescent lamps turn off. It is advisable to remove carpets and furniture as much as possible; they knock down the device, causing some error.

The survey is carried out slowly and data is recorded carefully. The scheme is simple.

The first stage of work takes place indoors. The device is moved gradually from doors to windows, paying attention Special attention corners and other joints.

The second stage - inspection with a thermal imager external walls buildings. The joints are still carefully examined, especially the connection with the roof.

The third stage is data processing. First, the device does this, then the readings are transferred to the computer, where the corresponding programs complete the processing and produce the result.

If the survey was carried out by a licensed organization, it will issue a report with mandatory recommendations based on the results of the work. If the work was carried out in person, then you need to rely on your knowledge and, possibly, the help of the Internet.

The question of calculating the amount of payment for heating is very important, since consumers often receive quite impressive amounts for this utility service, at the same time having no idea how the calculation was made.

Since 2012, when the Decree of the Government of the Russian Federation of May 6, 2011 No. 354 “On the provision of utility services to owners and users of premises in apartment buildings and residential buildings” came into force, the procedure for calculating the amount of heating fees has undergone a number of changes.

Calculation methods changed several times, heating provided for general house needs appeared, which was calculated separately from heating provided in residential premises (apartments) and non-residential premises, but then, in 2013, heating again began to be calculated as a single utility service without splitting the fee.

The calculation of the heating fee has changed since 2017, and in 2019 the calculation procedure changed again; new formulas for calculating the heating fee have appeared, which are not so easy for an ordinary consumer to understand.

So, let's sort it out in order.

In order to calculate the heating fee for your apartment and choose the necessary calculation formula, you must first know:

1. Does your house have a centralized heating system?

This means whether thermal energy is supplied to your apartment building for heating needs already in finished form using centralized systems or the thermal energy for your home is produced independently using the equipment included in the common property owners of premises in apartment building.

2. Is your apartment building equipped with a common building (collective) metering device and are there any individual devices metering thermal energy in residential and non-residential premises of your home?

The presence or absence of a common house (collective) metering device in the house and individual metering devices in the premises of your home significantly affects the method of calculating the amount of heating fees.

3. How are you charged for heating – during the heating period or evenly throughout the calendar year?

The payment method for heating utilities is accepted by the authorities state power subjects Russian Federation. That is, in different regions of our country, heating fees may be charged differently - throughout the year or only during the heating season, when the service is actually provided.

4. Are there any rooms in your house that do not have heating devices (radiators, radiators), or that have their own sources of thermal energy?

It was from 2019, in connection with court decisions, the trials of which took place in 2018, that the calculation began to include premises in which there are no heating devices (radiators, radiators), which is provided for in the technical documentation for the house, or residential and non-residential premises, the reconstruction of which, providing for the installation of individual sources of thermal energy, was carried out in accordance with the requirements for reconstruction established by the legislation of the Russian Federation in force at the time of such reconstruction. Let us remind you that previously the methods for calculating the amount of heating fees did not provide for a separate calculation for such premises, so the charges were calculated on a general basis.

In order to make the information on calculating the heating fee more understandable, we will consider each method of charging separately, using one or another calculation formula using a specific example.

When choosing a calculation option, you must pay attention to all the components that determine the calculation methodology.

Below are various calculation options, taking into account individual factors that determine the choice of calculating the heating fee:

Calculation No. 1: Amount of heating fee in residential/non-residential premises during the heating season.

Calculation No. 2: Amount of heating fee in residential/non-residential premises, there is no administrative budget for an apartment building, the amount of the fee is calculated during the calendar year(12 months).
Read about the procedure and example of calculation →

Calculation No. 3: Amount of heating fee in residential/non-residential premises, an ODPU is installed on an apartment building, There are no individual metering devices in all residential/non-residential premises.

On initial stage When arranging a heat supply system for any property, the heating structure is designed and the corresponding calculations are carried out. It is imperative to calculate the heat loads in order to find out the volumes of fuel and heat consumption required to heat the building. This data is required to decide on the purchase of modern heating equipment.

Thermal loads of heating systems

The concept of thermal load defines the amount of heat that is given off by heating devices installed in a residential building or at a facility for other purposes. Before installing the equipment, this calculation is performed in order to avoid unnecessary financial costs and other problems that may arise during the operation of the heating system.

Knowing the basic operating parameters of the heat supply design, it is possible to organize the efficient operation of heating devices. The calculation contributes to the implementation of the tasks facing the heating system, and the compliance of its elements with the standards and requirements prescribed in SNiP.

When the heating load is calculated, even the slightest mistake can lead to big problems, since based on the data received, the local housing and communal services department approves limits and other expenditure parameters, which will become the basis for determining the cost of services.

The total thermal load on a modern heating system includes several basic parameters:

load on the heating supply structure;
the load on the floor heating system, if it is planned to be installed in the house;
load on the system natural and/or forced ventilation;
load on the hot water supply system;
load associated with various technological needs.

Characteristics of the object for calculating thermal loads

The correctly calculated heat load for heating can be determined provided that absolutely everything, even the slightest nuances, are taken into account in the calculation process.

The list of parts and parameters is quite extensive:

purpose and type of property. To make the calculation, it is important to know which building will be heated - a residential or non-residential building, an apartment (read also: " "). The type of building determines the load rate determined by the companies supplying heat, and, accordingly, the costs of heat supply;
architectural features . The dimensions of external fences such as walls, roofing, flooring and sizes of window, door and balcony openings. The number of floors of a building, as well as the presence of basements, attics and their inherent characteristics are considered important;
temperature standards for each room in the house. This implies a temperature for the comfortable stay of people in a living room or area of an administrative building (read: " ");
design features of external fences, including the thickness and type of building materials, the presence of a thermal insulation layer and the products used for this;
purpose of premises. This characteristic is especially important for industrial buildings, in which for each workshop or area it is necessary to create certain conditions regarding the provision of temperature conditions;
the presence of special premises and their features. This applies, for example, to swimming pools, greenhouses, baths, etc.;
degree of maintenance. Availability/absence of hot water supply, centralized heating, air conditioning system, etc.;
number of points for collecting heated coolant. The more there are, the greater the thermal load exerted on the entire heating structure;
number of people in the building or living in the house. From given value humidity and temperature, which are taken into account in the formula for calculating the thermal load, directly depend;
other features of the object. If this industrial building, then they can be the number of working days during the calendar year, the number of workers per shift. For a private house, they take into account how many people live in it, how many rooms, bathrooms, etc.

Calculation of heat loads

The calculation of the building's thermal load relative to heating is carried out at the stage when a real estate object of any purpose is being designed. This is required in order to avoid unnecessary spending and choose the right heating equipment.

When carrying out calculations, norms and standards are taken into account, as well as GOSTs, TKP, SNB.

When determining the thermal power value, a number of factors are taken into account:

Calculating the thermal loads of a building with a certain degree of margin is necessary in order to prevent unnecessary financial expenses in the future.

The need for such actions is most important when arranging heat supply country cottage. In such a property, installation additional equipment and other elements of the heating structure will be incredibly expensive.

Features of calculating thermal loads

Calculated values of indoor temperature and humidity and heat transfer coefficients can be found in specialized literature or from technical documentation, supplied by manufacturers to their products, including heating units.

The standard methodology for calculating the thermal load of a building to ensure its effective heating includes the sequential determination of the maximum heat flow from heating devices (heating radiators), the maximum consumption of thermal energy per hour (read: ""). Also required to know total consumption thermal power over a certain period of time, for example, during the heating season.

Calculation of thermal loads, which takes into account the surface area of devices involved in heat exchange, is used for different real estate objects. This calculation option allows you to most correctly calculate the parameters of the system, which will provide efficient heating, as well as carry out energy inspections of houses and buildings. This is an ideal way to determine the parameters of standby heating supply industrial facility, implying a decrease in temperature during non-working hours.

Methods for calculating thermal loads

Today, thermal loads are calculated using several main methods, including:

calculation of heat loss using aggregated indicators;
determination of heat transfer from heating and ventilation equipment installed in the building;
calculation of values taking into account various elements enclosing structures, as well as additional losses associated with air heating.

Enlarged calculation of thermal load

An integrated calculation of the thermal load of a building is used in cases where there is insufficient information about the designed object or the required data does not correspond to the actual characteristics.

To carry out such heating calculations, a simple formula is used:

Qmax from.=αхVхq0х(tв-tн.р.) x10-6, where:

α is a correction factor that takes into account the climatic characteristics of the specific region where the building is being built (applied when the design temperature differs from 30 degrees below zero);
q0 is the specific characteristic of heat supply, which is selected based on the temperature of the coldest week during the year (the so-called “five-day week”). Read also: “How the specific heating characteristic of a building is calculated - theory and practice”;
V – external volume of the building.

Based on the above data, a larger calculation of the thermal load is performed.

Types of thermal loads for calculations

When making calculations and choosing equipment, different thermal loads:

Seasonal loads, having the following features:
They are characterized by changes depending on the ambient air temperature outside;
- presence of differences in the amount of thermal energy consumption in accordance with climatic features region of location of the house;
- change in the load on the heating system depending on the time of day. Because the outer fences are heat resistant, this parameter considered insignificant;
- heat consumption ventilation system depending on the time of day.
Constant thermal loads. In most heating and hot water supply systems they are used throughout the year. For example, in warm time year heat energy consumption compared to in winter decrease by about 30-35%.
Dry heat. It represents thermal radiation and convection heat exchange due to other similar devices. This parameter is determined using the temperature of a dry thermometer. It depends on many factors, including windows and doors, ventilation systems, various equipment, and air exchange occurring due to the presence of cracks in the walls and ceilings. The number of people present in the room is also taken into account.
Latent heat. Formed as a result of the process of evaporation and condensation. Temperature is determined using a wet thermometer. In any room for its intended purpose, the humidity level is affected by:
The number of people simultaneously present in the room;
- availability of technological or other equipment;
- flows of air masses penetrating through cracks and cracks in the building envelope.

Thermal load regulators

The set of modern boilers for industrial and domestic use includes RTN (thermal load regulators). These devices (see photo) are designed to maintain the power of the heating unit at a certain level and prevent surges and dips during their operation.

RTN allows you to save on heating bills, since in most cases there are certain limits and they cannot be exceeded. This is especially true for industrial enterprises. The fact is that for exceeding the thermal load limit, penalties are imposed.

It is quite difficult to independently make a project and calculate the load on the systems that provide heating, ventilation and air conditioning in a building, so this stage of work is usually entrusted to specialists. However, if you wish, you can perform the calculations yourself.

Gav - average hot water consumption.

Comprehensive calculation of thermal load

In addition to theoretical solutions to issues related to thermal loads, a number of practical activities are carried out during design. Comprehensive thermal inspections include thermography of all building structures, including floors, walls, doors, and windows. Thanks to this work, it is possible to determine and record various factors, influencing the heat loss of a home or industrial building.

Thermal imaging diagnostics clearly shows what the real temperature difference will be when a specific amount of heat passes through one “square” of the area of the enclosing structures. Thermography also helps determine

Thanks to thermal surveys, the most reliable data regarding thermal loads and heat losses for a specific building over a certain time period is obtained. Practical activities allow us to clearly demonstrate what theoretical calculations cannot show - problem areas future building.

From all of the above we can conclude that calculations of heat loads for hot water supply, heating and ventilation are similar hydraulic calculation heating systems are very important and should definitely be completed before the installation of a heating system in own home or at a facility for another purpose. When the approach to work is carried out competently, trouble-free operation of the heating structure will be ensured, and without extra costs.

Video example of calculating the heat load on a building heating system: