What power should the gas boiler be

Floor gas gas consumption: daily normative consumption example of calculations with formulas

When choosing a boiler equipment for the heating system, a very restless thought is persistently drilled. And how voracious the unit will be? Surely the answer will appear when the heating will work, and the counter will begin to count the gas consumption of the floor boiler, regularly wrapping speeds. However, it will be too late to be lamented if the amounts for payment for gas are not pleased.

Competent sales consultants, of course, answer most of the questions that arise, you can always seek help and to a competent engineer, but at least basic knowledge yourself have at least basic.

Find out from this article as much as possible about the methods of calculating energy consumption and factors that must be taken into account in the calculations. Below you are waiting not only boring formulas, but also examples. At the end. About what can be done to reduce gas consumption.

Gas, solid fuel, liquid fuel or electric

For household operation, 4 sources of thermal energy (4 types of fuel) are used:

• Gas. Gas boilers have earned the most widespread, they account for more than 60% of demand. The use of natural gas as a fuel is one of the most profitable options. Gas has a high heat transfer, when combustible, it forms a minimum amount of toxic combustion products, and large areas and tanks are not required to store it. At the same time, gas boilers differ in affordable (the best models of the average price segment within 19-28 thousand. ), have a high efficiency (on average 88-94%), the most developed and functional automation, work for weeks without human intervention. In general, the industry of gas boilers is most developed and competitive: for the buyer, this means the presence of increasingly affordable economical models of high quality, as well as a developed service structure (both in MSC and St. Petersburg, and in the regions).
• Solid fuel (firewood, coal, pellets). Solid fuel boilers occupy about 7-15% of the market and are still widely used in places of absence of a gas line or regions with the possibility of access to solid fuel for a symbolic price. Disadvantages of solid fuel boilers are known to everyone. This is an unstable release of thermal energy, the need for fuel harvesting, organizing a place for its storage, constant trampling and cleaning the boiler unit. To maintain combustion of boilers on wood, it is necessary to intervent a person on average every 2-4 hours, for coal boilers-5-10 hours, depending on the type of coal. Nevertheless, there are more autonomous and more comfortable in operation of a long.Term burning model. There are also pellet boilers with a fully automated fuel supply.
• Liquid fuel (diesel, waste oil, fuel oil, kerosene). Diesel boilers and boiler units operating in working out about 10% of the market and are universal. Liquid fuel boilers are installed exclusively in a separate room for a boiler room, require a tank for storing fuel (in a boiler room or outside the house), but they have a high efficiency, are able to work absolutely autonomously, when burned, they form a minimum of toxic exhausts, and the cost of fuel is often much lower than gas. The most affordable and profitable models are diesel navien and kiturami, which differ from gas counterparts only by the device of the burner.
• Electricity. Electrchots are almost ideal in terms of comfort of operation and functionality, however, the cost of electricity is the highest and for full heating of a house with an area of ​​100 kV. M. Can leave from 7 to 10 thousand. Per month. It is most rational to use an electric boiler with temporary residence in the house, then the low cost of the boiler and heating system for a long time will pay for operating costs for a long time. Also, use options for a pair with a buffer container, accumulating heat developed by a boiler at a reduced night tariff, or use as a reserve boiler unit.

Summarizing if a gas line is held near the house, we recommend, without hesitation, choosing a gas boiler. If the gas line is absent, it is worth choosing based on personal preferences to the method of maintaining combustion, the availability of fuel in the region, the requirements for autonomy, the cost of the boiler and its installation.

The main nuances of choosing a gas boiler

The absence or constant interruptions in central heating and hot water supply force the owners of cottages and city apartments to create their own autonomous systems.

Their main element is the boiler, which, due to the burning of the fuel, heats the coolant for the heating system and water for household needs.

The choice in favor of gas equipment is due to the efficiency of use as a gas fuel. All other options for the burned fuel are more expensive or give less heat at times.

Plus modern heaters of this species do not require constant supervision. I connected the installation to the trunk or cylinder, and it works uninterruptedly while there is something to burn.

The use of natural gas is the optimal for fuel costs and operational maintenance costs for heating a private house

However, in order for the gas boiler to function properly and in optimal mode, it is necessary to correctly select it when buying and regularly service after connecting.

There are a lot of differing in the functionality and special modules inside the models of this equipment. The acquisition of a heating unit on gas should be approached thoughtfully.

There are a lot of criteria for choosing a gas boiler, but the main ones are:

• Power issued by the device.
• Layout solution (number of contours, type of body and heat exchanger material).
• Place for installation.
• Automation for safe operation.

All these issues are closely related. Lack of space for a large unit or a desire to mount a device with aesthetic appearance in the kitchen forces you to choose a wall model of lower power than the floor version. And the need to heat hot water for the washbasin and the soul makes you look for a boiler with two contours.

When choosing a heater, you should remember the need to repair it, if there is no workshop for servicing the selected model nearby, then it is worth looking for a different option

An example of calculating thermal losses

As an example, we calculate the heat loss of the house with specified characteristics.

The figure shows the plan of the house for which we will calculate heat loss. When compiling an individual plan, it is important to correctly determine the orientation of the walls relative to the side of the world, calculate the height, width and length of the structure, as well as note the location of the window and doorways, their dimensions

Based on the plan, the width of the structure is 10 m, the length is 12 m, the height of the ceilings is 2.7 m, walls are oriented to the north, south, east and west. 3 windows are built in the western wall, two of them have dimensions 1.5×1.7 m. One. 0.6×0.3m.

When calculating the roof, a layer of insulation is taken into account, finishing and roofing material. Steam and waterproofing films that do not affect thermal insulation are not taken into account

Doors with dimensions 1 are built in the southern wall.3 × 2 m, there is also a small window 0.5 × 0.3m. Two windows 2 are located on the east side.1 × 1.5 m and one 1.5 × 1.7 m.

• Walls of the walls of the wood.Fiber plate (isopylet) from the outside and from the inside. 1.2 cm each, coefficient. 0.05.
• Glass wool located between the walls, its thickness 10 cm and coefficient. 0.043.

The thermal resistance of each of the walls is calculated separately, t.To. The location of the structure relative to the cardinal points, the number and area of ​​the openings are taken into account. The results of the calculations on the walls are summarized.

The floor is multi.Layer, throughout the area is made according to one technology, includes:

• Cut boiled board, its thickness 3.2 cm, thermal conductivity. 0.Fifteen.
• A layer of dry alignment of a wood-bruise plate 10 cm thick and a coefficient of 0.Fifteen.
• Insulation. Mineral wool 5 cm thick, coefficient 0.039.

Suppose that the floor worsening the heating equipment and the floor does not have such holes. Therefore, the calculation is made for the area of ​​all rooms according to a single formula.

Suppose that the ceiling ceiling also does not have an exit to the attic over a living or household premises.

The house is located in the Bryansk region, in the city of Bryansk, where the critical negative temperature is.26 degrees. Experimentally established that the temperature of the Earth is 8 degrees. Desired temperature in the room 22 degrees.

Calculation of thermal losses of walls

To find the total thermal resistance of the wall, first it is necessary to calculate the thermal resistance of each of its layer.

The glass wool layer has a thickness of 10 cm. This value must be translated into meters, that is:

Got a value in = 0.One. Thermal conductivity of thermal insulation. 0.043. We substitute the data into the thermal resistance formula and get:

By a similar example, we calculate the resistance to the heat of the isopylet:

The total thermal resistance of the wall will be equal to the sum of the thermal resistance of each layer, given that the layer of the wood.Fiber plate we have two.

Having determined the total thermal resistance of the wall, you can find thermal losses. For each wall, they are calculated separately. Calculate Q for the North Wall.

Additional coefficients allow you to take into account the features of the heat loss of the walls located in different aspects of the world in the calculations

Based on the plan, the northern wall has no window holes, its length is 10 m, height is 2.7 m. Then the area of ​​the wall S is calculated by the formula:

We calculate the DT parameter. It is known that the critical temperature of the environment for Bryansk26 degrees, and the desired temperature in the room is 22 degrees. Then

For the north side, the additional coefficient l = 1 is taken into account.One.

The table shows the thermal conductivity coefficients of some materials that are used in the construction of the walls. As you can see, mineral wool passes through itself the minimum amount of heat, reinforced concrete. Maximum

Having made preliminary calculations, you can use the formula for calculating heat loss:

We calculate the heat loss for the western wall. Based on the data, 3 windows are built into it, two of them have dimensions 1.5×1.7 m and one. 0.6×0.3m. We calculate the area.

From the total area of ​​the western wall it is necessary to exclude the area of ​​the windows, because their heat loss will be different. To do this, you need to calculate the area.

For calculations, heat loss will use the area of ​​the wall without taking into account the area of ​​the windows, that is:

For the western side, the additional coefficient is 1.05. The resulting data is set in the main formula for calculation of heat loss.

We make similar calculations for the eastern side. There are 3 windows here, one has dimensions 1.5×1.7 m, two others. 2.1×1.5 m. We calculate their area.

From the total area of ​​the wall we subtract the values ​​of the window area:

Additional coefficient for the eastern wall.One.05. Based on the data, we calculate the thermal losses of the eastern wall.

On the southern wall is a door with parameters 1.3×2 m and window 0.5×0.3m. We calculate their area.

We determine the area of ​​the wall excluding windows and doors.

We calculate the heat loss of the southern wall, taking into account the coefficient L = 1.

Having determined the heat loss of each of the walls, you can find their common thermal losses according to the formula:

As a result, the loss of the heat of the walls was 1810 watts per hour.

Calculation of thermal losses of windows

There are 7 windows in total, three of them have dimensions 1.5 × 1.7 m, two. 2.1 × 1.5 m, one. 0.6 × 0.3 m and one more. 0.5 × 0.3m.

Windows with dimensions 1.5 × 1.7 m is a PVC profile two-chamber C and-glass. From the technical documentation, you can find out that its R = 0.53. Windows with dimensions 2.1 × 1.5 m two-chamber with argon and I-glass, have thermal resistance R = 0.75, windows 0.6×0.3 m and 0.5 × 0.3. R = 0.53.

It is also important to take into account the orientation of the windows relative to the parties to the world.

Our calculator for quick calculation

To calculate the thermal power of the heating boiler in this calculator, just enter the area of ​​the heated room, select the necessary parameters and press the “Calculation” button.

Above, fairly simple options were given how to calculate the power of the heating boiler. It should be remembered that for buildings of a more complex design, these methods can be unsuitable if:

• The building has rooms with different heights of ceilings;
• A warm floor is planned;
• The construction of objects is designed that will require additional heat consumption (pool, greenhouse, sauna, etc. P.).

These points should be taken into account at the design stage. The most accurate calculation of the capacity of heating equipment can be calculated by the engineers-vehicle. All the necessary calculations can be carried out at the stage of designing the premises.

What is the power of the boiler and how to find it out

The thermal power of the boiler is the maximum amount of thermal energy transmitted by the coolant during the combustion of the fuel (measured in kilowatts/hour or just kW). This means that a boiler with a capacity of 20 kW with continuous operation at maximum power per hour will develop and transfer the coolant 20 kW of thermal energy.

You can determine the power of the boiler in several ways:

• Look for a list of technical characteristics on the housing of the boiler unit;
• Find the value in the Passport of Models. If the documentation is not preserved, you can look for an electronic version or study the offers of online stores that necessarily indicate in the description of the model its rated power;
• If we are talking about a gas boiler, you can find out the approximate heat production of gas consumption, for which it is necessary to check and fix how many cubic meters the boiler consumes with continuous operation at maximum power. The specific heat of gas combustion is constant and equal to 9.3 kW. It is also important to consider the boiler efficiency (it can also be found in the list of technical characteristics), for old Soviet models these are values ​​in the region of 70-85%, in new efficiency models within 86-94%. Total, maximum power = 9.3 kW (specific heat of combustion of natural gas) 0.8 (if the efficiency is 80%) 2.5 cubic meters. M/h (the resulting gas consumption per hour) = 18.6 kW. In a similar way, you can calculate approximate values ​​for a solid fuel, liquid.Fuel or electric boiler.

It is impossible to increase the heat production of a household boiler without serious unsafe changes in its design, therefore, it is necessary to approach the choice of the minimum necessary power responsibly. If it is not enough, you will have to install an additional boiler unit or insulate walls, floor and ceiling, replacement of windows and doors in order to reduce heat loss.

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 Moscow and the Moscow 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 Moscow 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 Moscow region:

Advantages of natural gas boilers

Small costs for heating private households using a gas boiler is not the only advantage of equipment of this type. Of the other advantages and advantages of heating equipment on natural gas, we note the following:

• Developed automation systems allow with a high degree of accuracy to withstand specified climatic parameters in heated rooms, which is another effective factor in savings;
• Multi.Stage gas safety systems completely eliminate the leakage of natural gas, which eliminates the main drawback of natural gas. Its explosion hazard;
• Small dimensions and the relatively low cost of boiler equipment on natural gas increase the total economic effect of the low cost of fuel;
• High reliability of the equipment and its high efficiency reduce the operational costs of maintenance, checking and repair of gas boilers with natural gas;
• Built.In heat exchangers for the preparation of hot water of double.Circuit models of heating equipment reduce the cost of a comprehensive heating system;
• Relatively small dimensions and all boiler equipment can significantly save space for the boiler room, which qualitatively improves the consumer properties of a country house;
• Small power consumption from the AC network allows you to install relatively inexpensive sources of uninterrupted power, which qualitatively improves the operating conditions of boiler equipment and the entire heating system as a whole;
• Automation of the heating system on natural gas makes it possible to easily install remote devices for managing the operation of heating equipment. Such a feature has proven itself for suburban possessions, the tenants of which are often absent at home.

Conclusion: The general course of the government to simplify the process of gasification of households gradually eliminates the main drawback of natural gas. The high cost of local gas distribution networks.Conclusion

Analysis of all factors of calculating the power of a gas boiler for heating a private house convincingly shows that the indicative calculation of the power characteristics of heating equipment gives adequate values ​​for most new and already built country houses. The small amount of reserve serves as a reliable insurance from unforeseen situations, and also guarantees the operation of equipment with the maximum utility coefficient.

This material also shows that for houses of complex configuration with a large glazing area, the simplest calculation methods are not a guarantee of obtaining the correct result, and for competent calculation of heating equipment parameters, it is better to contact qualified specialists or use professional online calculators with the necessary set of architectural characteristics of the house.