How to calculate the power of a gas boiler for the house
The power of the gas boiler is an important parameter on which the comfort of living in the premises heated by it depends. To choose the best option for a home or apartment, you need to consider their size. The necessary performance of heating equipment depends on the area of heated premises and some other, less significant factors.
The boiler should not only replenish all thermal losses of a particular building or premises, but also have a certain powerful supply. Why it is necessary to take the value more than the calculated:
- The equipment should not work at the limit of capabilities. this leads to premature wear;
- It is necessary to take into account the probability of abnormal temperatures;
- For a private house, it is useful to take into account the possibility of expanding the area.
Some buyers do not know in which units the main parameter of gas equipment is calculated that determines its performance. Thermal power of the devices is measured in kilowatts (kW). This value is always indicated in the technical passport of each model.
What affects heat loss
To find out what equipment productivity is needed, in addition to the area, other factors need to be taken into account:
When using turbocharged devices, it is also necessary to take into account the amount of energy spent on air heating.
To determine the performance of the boiler, you must first calculate the heat loss. Thermal calculation is characterized by increased complexity, as it takes into account a huge number of components:
- the materials from which the walls, ceilings, roofs, etc.D.;
- type of heating system;
- the presence of the “warm floor” system;
- household appliances releasing heat.
Professionals use thermal imagers, and then perform calculations according to complex formulas. It is clear that ordinary user will not have to understand the nuances of heating equipment. for them there are affordable methods that allow them to quickly and accurately calculate the optimal heat production of equipment.
Methods of calculating power
There are several ways of an approximate (evaluative) calculation of boilers for heating the house. And the accuracy of the results will depend on the complexity of the algorithm. The more factors taken into account, the less the probability of error.
Calculation by area
One of the most popular ways to calculate the power of the heating boiler is the area of the house. They are often used by sellers in heating equipment stores when advising customers. To calculate the power (in kW), the total area of the premises (in m 2) is divided by 10.
The disadvantages of this simple formula are that it “works” only for the middle strip does not take into account the heights of the ceiling of the premises, the quality of insulation of the facade walls and many other factors. It can only be used to assess power, since the error of the result can reach 40 %.
In some sources, the authors propose to use correction factors to adjust the result.
How it works, it is difficult to understand, since “bad” and “good” are only subjective assessments, and not specific data showing the resistance to heat transfer. A similar story is with correctional coefficients for glazing. It changes depending on the number of glasses in the package, but does not take into account the window area.
Pay attention to the work of the online filter in the Catalog of Teplodar: if you set the area of 100 m 2. then in the results of the issue will be Kupper boilers with a capacity of 10 to 15 kW.
On the sites of many manufacturers of boiler equipment-mainly foreign-you can find the so-called online calculators, with which you can choose the power of the boiler for heating your own house. The algorithms of most of them are built on the calculation of heat loss. the most accurate methodology today, which gives unmistakable results.
To calculate the power of the boiler, the “correct” online calculator will require an impressive list of source data:
The difference in external and internal temperatures. In order not to get a lack of power, it is recommended to take the minimum values on the coldest days. Heat loss grow with an increase in temperature difference linear. Area, thickness and material of all facade walls. The calculators laid the heat transfer coefficients for most known structural and thermal insulation materials. If the facade walls have a multilayer structure (complex insulation pie), you need to indicate the material and thickness of each layer, including vapor barrier and windproof films. In some houses, living rooms are adjacent not to the street, but with unheated rooms. Heat goes through partitions separating them, but the calculation formula is slightly different from the algorithm for facade walls. Foundation and roof data. The proximity with unheated basement and attics is also taken into account. If you are calculating the power of a gas boiler for a city apartment in a multi.storey building, which is located on the middle floors, the floor and ceiling are “thrown away” from the list of sources of heat loss. Glazing area and data on the number of cameras in double.glazed windows. The calculation algorithm is designed for houses and apartments built on standard projects and having radiator heating. For rooms with panoramic glazing “from floor to ceiling” and channel radiators with forced convection, you need a completely different calculation principle. Thermal devices of this type create an effective air curtain, which is not only source of heating, but also an additional layer of thermal insulation. Forced and natural ventilation performance. You can insulate the walls endlessly, but ventilation will remain the source of heat loss. The house should not be thermos and the frequency of air exchange should comply with sanitary requirements.
The main problem of choosing the power of the heating boiler using an online calculator is that it “knows” far from all wall building materials. In this case, you have to look for data on them on your own, and you manually perform calculations. This is a more time.consuming process, and the probability of error here depends on attentiveness.
There are several points that need to be taken into account when adding power to preparation of sanitary hot water. The calculation principle depends on the method of its heating. There are boilers with the priority of the hot water and without it. The former is a painting wall models with a secondary heat exchanger, which performs the functions of a flow water heater. The second. single.circuit with an indirect heating boiler (accumulative capacity). If you select a wall gas boiler for a small house or apartment, its calculated power without taking into account the DHW rarely exceeds 10. 12 kW. However, for heating water in blank mode, it is necessary at least 20 kW. Accordingly, you will receive an excess of heating power. Pay attention to the parameters of the main burner: it should have a stepped or smooth power modulation.
If an indirect heating boiler is used, its passport power and the daily flow of hot water are needed. According to these data, you can calculate the heat loss at the hot water.
Power of the Kupper boilers
Our company produces solid fuel boilers Kupper in a wide range of capacities. You can choose a model for heating the garage, cottage, large private house or cottage. We offer boilers with a capacity of 10 to 42 kW, characterized by high operational reliability. Our equipment can be operated in heating systems with forced and natural circulation.
In the online store of the Teplodar company you will also find hydraulic separators with the heat accumulator function. These devices allow us to operate the heating system with an excess capacity boiler.
Gas Boilers or Electric Heating. Which is Cheaper UK 2022
To get advice on choosing heating boilers and hydraulic dividers, as well as order equipment, contact the Consultants of the Teplodar by contact phone.
Nast and high power boilers
Wall gas boilers of low power, for example, in 8-20 kW it is advisable to use a small area for heating of country houses or premises of a small area. Typically, such units have one outline and work only on heating. Most wall models have a capacity of 10 to 40 kW, but some manufacturers produce units up to 55 kW. They are able to warm the house up to 600 m². These include the following models: Baxi Luna Duo-Tec MP 1.60, Nova Florida Pictor Condensing Line Tech KR 55, Beretta Novella 55 RAI and others.
Boilers that have a capacity of 40 kW, for the most part are condensation. Their efficiency is about 108-110%. For example, wall-mounted gas condensation boilers with a capacity of 40 kW will be able to heed an area of up to 300 m² and provide 4-5 people with water.
note! If you want to heat the rooms up to 600 m², then you can purchase models of units that are connected to the cascade. This method makes it possible to connect up to 16 units.
When choosing a condensation boiler, it should be borne in mind that the effectiveness of its work largely depends on the characteristics of the heating system. The low.temperature system will be optimal, in which the coolant in the reverse circuit does not heat up more than 60 ° C.
About how to choose the right power of a gas boiler, see the video.
Gas boiler for houses of standard configuration
Calculating the power of a gas boiler for houses created according to a standard project is not too difficult. In such buildings, the height of the ceiling does not exceed three meters. To do this, use the formula: MK = SUMK/10, where
- MK is the estimated power of the boiler in kW;
- S is the total area of the room in KV.m;
- UMK. the specific power of the boiler, which should be for every 10 square meters. m.
The last indicator is set depending on the climatic zone and is:
- 0.7-0.9 kW for the southern regions;
- 1.0-1.2 kW for the middle strip;
- 1.2-1.5 kW for sub-regions;
- 1.5-2.0 for the northern regions.
According to this formula, the estimated power of the boiler for a house with an area of 200 kV. m., which is located in the middle lane, will be: 200×1.1/10 = 22 kW. Please note that this formula shows how to calculate the power of the boiler, which is used only for heating the house. If the use of a double.circuit system providing for water heating for household needs is supposed to increase the capacity of the equipment by another 25%.
How to take into account the height of the ceilings during calculations?
Since many private houses are built according to individual projects, the methods of calculating the capacity of the boiler given above are not suitable. To make a sufficiently accurate calculation of the gas heating boiler, you must use the formula: MK = Q.CCPAZ, where:
- MK. estimated power of the boiler, kW;
- Qt. predicted heat loss, kW;
- KAZ. stock coefficient, which is 1.15 to 1.2, t. E15-20%, for which experts recommend increasing the calculated capacity of the boiler.
The main indicator in this formula is the predicted heat loss of the structure. To find out their value, you need to use another formula: Qt = VRTK/860, where:
- V. volume of room, cube.m.;
- PT. the difference in external and internal temperatures in degrees Celsius;
- k is the dispersion coefficient, which depends on the thermal insulation of the building.
The dispersion coefficient varies depending on the type of building:
- For buildings without thermal insulation, which are simple structures made of wood or corrugated iron, the dispersion coefficient is 3.0-4.0.
- For structures with low thermal insulation, characteristic of buildings with single masonry of brick with conventional windows and roof, the dispersion coefficient is taken equal to 2.0-2.9.
- For houses with an average level of thermal insulation, for example, buildings with double brickwork, a standard roof and a small number of windows take a dispersion coefficient of 1.0-1.9.
- For buildings with high thermal insulation, well-insulated floor, roof, walls and windows with double-glazed windows, the dispersion coefficient is used in the range of 0.6-0.9.
For small buildings with good thermal insulation, the estimated capacity of heating equipment can be very small. It may happen that the market simply does not have a suitable gas boiler with the necessary characteristics. In this case, equipment should be purchased, the power of which will be slightly higher than the calculated. Automatic heating control systems will help smooth out the difference.
Some manufacturers took care of the convenience of customers and posted on their Internet resources special services that allow without any problems to calculate the necessary capacity of the boiler. To do this, you need to enter data such as:
- the temperature that should be maintained in the room;
- the average temperature in the coldest week of the year;
- need for DHW;
- the presence or absence of forced ventilation;
- the number of floors in the house;
- ceiling height;
- information about the ceilings;
- information about the thickness of the external walls and the materials from which they are made;
- information about the length of each wall;
- information about the number of windows;
- Description of the type of windows: number of cameras, glass thickness, etc.P;
- The dimensions of each window.
After all the fields are filled, it will be possible to find out the calculated power of the boiler. Details of detailed calculations of boilers of various types are clearly presented in the table:
In this table, some options are already calculated, you can use them as correct in advance (click on the picture to increase)
The documentation necessary for installing a double.circuit boiler in the apartment
Obtaining a permit from a gas supply company is only the first step towards installing gas heating in the apartment. The next sequence of actions is this:
- After receiving the permission, it is necessary to order a project for installing a gas unit. This should be done only in a company that specializes in such documentation.
- A fire supervision worker must check the performance of ventilation and chimneys. If everything is in order, you will be given permission to install the boiler. If there are problems, then an act is issued, which indicates the required work to eliminate problems.
- If you are connected to the central water and heat supply, then you need to apply for a refusal of these services. Pay debts and specify when the shutdown work will be carried out.
- Now you need to purchase a gas meter, its data, together with the technical passport to the boiler, is attributed to the design organization. According to this information, a finished project is drawn up.
- A contract for servicing the unit in Gorgaz is concluded, in this organization you should also receive a signature for the project of gasification of the apartment.
- Having received the signed project, you can cut off the heat network.
- After that, the installation of a gas boiler is carried out.
- Gorgaz employees come and connect your unit to a centralized gas supply, adjust the equipment, seal the gas meter.
- In order for a guarantee from the manufacturer to the gas boiler, a mark of the master from the company’s service center is needed. He must come, check the device, make certain settings and put the stamp in the product passport.
The entire procedure for organizing gas heating in the apartment can take up to 3 months. Therefore, it is better to start it long before the start of the heating period. in late spring or early summer.
Judging by the reviews, a double.circuit gas boiler for the apartment is a rather economical and convenient option for obtaining heating and hot water supply. Although you can’t call the procedure for issuing a permit for the installation of the boiler, but it’s worth it.
What power supply is needed?
Under standard conditions and optimal insulation of the building, a power supply is required only for gas boilers of floor heating systems. In the case of a conventional wall boiler, the error in the consumption of heat is insignificant, so the power supply of power is completely optional. This will reduce your expenses for connecting and maintaining the entire heating system and protect you from buying an expensive boiler of greater power, which you never use in full.
Subscribe to our YouTube,. Yandex Zen. There is a lot of useful and interesting content there!
Which is important to take into account?
The indicator of boiler power is calculated by various calculation methods. It is important to take into account the configuration of heating equipment and other key parameters:
All boilers work on the basis of two sign principles:
Single.circuit wall.mounted gas boiler
One circuit involves a rather primitive and understandable device of boiler equipment. Structurally this:
The format version of the 2nd circuit puts in priority, heating the water carrier. Instant auto shutdown occurs if you use hot water. This is important not to encounter unpleasant problems due to the fact that the system was unjustifiably overloaded.
Systems in two circuits are pleasantly compact. They will require much less space for comfortable accommodation than in the case of two separate systems for heating and providing hot water to your home.
Also, the nuances of models can lurk in how boilers are placed in them.
You can install equipment of this category in different ways. Just to the surface of the floor or attach to one of the walls. Here everything is interconnected and takes into account such moments as:
Models involving the floor option of installation can be much more powerful than their wall analogues.
Management methods are also very diverse:
For electronic filling, round.the.clock access to electricity is required.
Why Gas Boilers Are Still The Most Popular Choice
Double.circuit gas boiler with an indirect heating boiler
How to calculate the power using engineering calculation formulas?
There is no single algorithm for calculations. Depending on whether you need a system with one contour or whether with two, the nature of the selection will differ significantly.
Formula for calculations for a specific standard project
If the house is built according to the developed typical project. The height of the rooms is not more than 3 m. Therefore, the total volume of premises is not taken into account. The power indicator is considered as follows:
First, calculated the specific indicator of thermal power: mind = 1 kW/10 m 2;
Then take the required value: RM = mind p kr. where
P. the sum of all areas to be heating,
KR –C. It is taken on the basis of the climate in which the building is placed.
For the southern regions, the amendment is 0.9. For the middle strip. 1.2. For the northern. 2. For and region. 1.5.
The calculation methodology is bad in that it does not take into account the internal factors of the house. They have a leading importance on the microclimate of housing. These values are very close to the perfect value.
Some manufacturers produce memo-recommendations, but for accurate calculations, they still recommend contacting specialists
Most companies, along with the equipment, produce special memos, but in order to accurately calculate the power, it is better to contact professionals
Calculation for a single.circuit version of the device in a room with an area of 100 m 2. If it is located within the boundaries of the region:
Calculations for double.circuit boilers
Double.circuit options for boiler equipment on gas mixtures work on other principles than their single.circuit colleagues:
- At first, water is heated, it is the heat carrier in this system;
- It goes into radiators that heat up and heat the surrounding air;
- The cooled heat carrier returns to the starting point for a new heating.
A closed circuit is created. The work is of the nature of the cycles of a certain length. Когда температура носителя тепла и окружающего воздуха становятся одинаковыми, активируется режим ожидания. There is a temporary pause in the heating of the water carrier of heat.
Also, the boiler conscientiously supplies hot water to the taps, and not to the heating system.
Heating system with two contours
To obtain the required level of boiler equipment on the basis of the gas mixture, the calculated value of the indicator by 20% should be increased.
Calculation for the two contour version of the boiler on the gas mixture for rooms with an area of 100m 2. We took the coefficient for the building erected in the region:
Calculation of the boiler power taking into account the insulation of the house
Each house or apartment has its own thermal insulation characteristics. For example, heat loss in brick and cinder block structures are very different. Also, the wall, laid out of one brick, will pass more heat than masonry from two bricks. And wooden walls without insulation lose heat even faster.
In addition to wall material, the presence of cracks in the window and door openings plays an important role. For example, modern plastic windows can save more heat than old wooden frames. Also if the door does not close tightly, heat will go through the cracks. To account for these criteria, there are dispersion factors:
- 0.6-0.9-for houses erected according to modern technologies: walls, roof and floor are insulated, installed hermetically closing windows and doors;
- 1-1.9-for buildings with an average level of thermal insulation: insulated walls, windows and roof;
- 2-2.9-for a low level of thermal insulation: walls from masonry into one brick with wooden frames without insulation;
- 3-4-for structures in which there is no thermal insulation, for example, a template made of wood.
Read here how to choose the optimal power of the boiler?
According to experts, thermal losses through different non.insulated parts of the house make up:
The formula, how to calculate the gas boiler for a private house, which takes into account the dispersion coefficient is the most accurate:
PT is the difference in temperature (it is necessary to subtract a possible minimum air temperature from the desired temperature in the room);
Thus, it turns out that the calculation of the necessary power of a gas boiler for heating a house with an average level of thermal insulation with an area of 100 m² and 2.7 m high is as follows:
Multiples the result by a coefficient of 1.15, which provides on top of another 15% power:
So, for heating this house you will need a gas boiler with a capacity of 27 kW.
What are the differences in the calculation of power for apartments?
Owners of apartments who want to organize gas heating in themselves are also actively interested in the question of how to calculate the gas boiler for the house. When calculating the power of the unit for the apartment, its location plays a significant role. whether it is surrounded by other rooms, is in the corner of the building or on the top floor. Which coefficient should be selected:
- 0.7. if there is another heated room above the apartment;
- 0.9. if a heated attic is located on top;
- 1. if the attic is not heated.
Thus, first you should calculate the power by the home formula, and then multiply by this coefficient.
When calculating the optimal power of a gas boiler for an apartment, SNiP norms are often used. They are based not on the area of the apartment, but on its volume. The norms stipulate how much heat is needed for heating 1 m³ of a certain standard building:
It turns out that for heating an apartment with an area of 65 m² and the height of the ceilings of 2.5 m of a brick house, the necessary power of the gas unit is calculated as follows:
- We find the volume of the apartment: 652.5 = 162.5 m³.
- Multiply by heat rate depending on the material 162.534 = 5525 W = 5.5 kW.
- We take into account that there is another heated apartment on top 5.50.7 = 3.86 kW.
- Now we multiply by the climatic coefficient of the middle lane similar to the calculation for the house 3.861.2 = 4.64. Add a power supply of 15% 4.641.15 = 5.34 kW. Round to 6 kW.
It should also be noted that it significantly affects the loss of heat from the apartment by the presence of walls going out into the street. Depending on their number, the correction factors are taken into account:
If it is assumed that the unit will provide hot water, then a supply is added to the power of 20-25%.
Another option for determining the power is to accurately calculate the heat loss of your house or apartment using a special thermal imager device. Its readings are substituted in power calculation formulas. At the same time, you can improve the situation and insulate some “weaknesses” of your home.
The simplest and fastest way to determine the desired performance of a gas boiler is an online calculator. It is enough to substitute only some characteristics of the house and a heated area in it. However, it is not known what algorithm this program calculates the algorithm. Therefore, it is better to check the result obtained on the calculator, comparing it with its calculations.