Modern solutions for space heating for various purposes today are huge. Despite this, most consumers still choose a gas boiler, which has been tested for years and is a traditional solution. Such equipment is reliable and durable, does not require complex and frequent maintenance, and the range allows you to choose the unit perfectly for any room.
Why is power so important
Among the main features of a gas boiler, its power should be highlighted. For a correct determination, many factors must be taken into account. The service life of the device, economy, as well as the climate in the house will depend on how correctly you choose this parameter.
Why is it necessary to calculate power
When choosing a gas boiler, you should be guided by measurements to understand what the source ofbuilding heat loss. If you purchase a unit with excess capacity, this can lead to unjustified fuel consumption, and therefore unnecessary expenses. If the power is not large enough, it can damage the equipment, as it will have to work to heat the house at high speeds.
Calculation of the power of a gas boiler is usually carried out according to the simplest scheme. It indicates that for every 10 m2 of a dwelling, a kilowatt of power is needed. Add about 15% to this value. From a simple formula it follows that if you have a house with an area of 100 m2, you will need a boiler with a capacity of 12 kW.
What is important to pay attention to
However, this approach is crude, and can only be used for buildings with effective thermal insulation and modern windows. In addition, there should be a mild climate outside, and the ceilings in the building should be low. As practice shows, not all private houses are suitable for these criteria.
Power detection
The calculation of the power of a gas boiler can be carried out using the example of a private house built according to a standard project. It provides for a ceiling height of 3 m. In this case, the formula will be universal. It will be important to take into account the construction area and the specific power of the boiler, which will be abbreviated UMK. This value will vary and depend on the climate zone.
If the house is built in the southern region of the country, then the specific power of the unit will range from 0.7 to 0.9 kW. Specific power ranging from 1 to 1.2 kW is used for the middle band. If the house is built in the Moscow region, the power of the device should correspond to 1.2-1.5 kW. For the north of the country, the specific power will be 1.5-2 kW. To calculate the power of a gas boiler, you should use a formula that looks like this: M \u003d S x UMK: 10. It is correct for a typical one-story or two-story house.
Calculation by example
As an example, consider a house with an area of 80 m22. If it is built in the northern region, then you can get the following calculations: 80 x 2: 10, which is equal to 16. The figure determines the power of the boiler that you should purchase. If you choose a double-circuit boiler, which performs the function of not only heating your home, but also heating water, add 20% to the resulting formula.
What heat loss should be taken into account when calculating power
The complete picture cannot be obtained, even taking into account the climatic zone in which the house is built. Some have plastic windows with double glazing, while others have not changed the old wooden frames. Other homeowners have insulated exterior walls, while other homeowners have homes where a single layer of brick separates the street from the room.
If you use averaged data, which are based on the calculations of experts, the most impressive heat loss occurs on non-insulated walls. About 35 percent of the heat escapes through them. Somewhat less (25%) is lost due to poorinsulated roof. Above the house, ideally, there should be a warm attic. But if the floor is poorly insulated, then heat loss will be about 15%. The same amount of heat escapes through old wooden windows. We should not forget about the ventilation system, as well as open windows, which account for about 15% of heat loss. As a result, the calculation of the power of a gas boiler, which is presented above, is not suitable for every residential building. For such cases, you should use your own scoring systems.
Calculation of power taking into account the dissipation factor
One of the important factors of heat exchange between the environment and a residential building is the dissipation coefficient. Depending on how well the building is insulated, you should use indicators that allow you to get the most accurate figure when applying the formula. If we are talking about a house where there is no thermal insulation at all, the dissipation factor will vary from 3 to 4. Most often these are temporary houses made of wood or corrugated iron.
When calculating the power of a gas boiler for heating, a coefficient from 2.9 to 2 should be used, which is suitable for buildings with insufficient thermal insulation. We are talking about houses without insulation and with thin walls, which are built in one brick. Instead of windows, there are usually wooden frames, and on top there is a simple roof. The coefficient will vary from 1.9 to 1 if the house has an average level of thermal insulation. This coefficient is assigned to buildings with double plastic double-glazed windows, thermal insulation of the facade or double masonry, as well asinsulated roof or attic.
Dissipation coefficient will be the lowest in the case of houses that are built using modern technologies and materials. Such buildings include those in which the floor, roof and walls are well insulated, as well as good windows are installed. Usually such buildings have a good ventilation system. The dispersion coefficient will be the lowest - from 0.6 to 0.9.
By calculating the power of a gas boiler for a house using a formula that contains the value of the dispersion coefficient, you will get the most accurate numbers for a particular building. The formula is: QT \u003d V x Pt x k: 860. Here, the QT value is the level of heat loss. The volume of the room is indicated by the letter V, and it can be determined by multiplying the height by the width and length of the room. The temperature difference is Pt. To calculate from the desired room temperature, subtract the minimum temperature that can be outside the window. The scattering coefficient in the formula is denoted by the letter k.
If you want to calculate the power of a double-circuit gas boiler, you can substitute the numbers in the above formula to find out the heat loss. The example will consider a house with a volume of 300 m33. The level of heat loss here will be average, and the desired indoor air temperature will be +20 ˚С. The minimum winter temperature is -20 ˚С. The calculation of the level of heat loss will look like this: 300 x 48 x 1.9: 860 ≈ 31.81. If you know this figure, you can calculate how much power the boiler will perform its task. For this, the value of heat lossyou need to multiply by the safety factor, which usually varies from 1.15 to 1.2. These are the same 15-20 percent. The result will be: 31.81 x 1.2=38.172. The figure can be rounded down, which will allow you to get the desired number.
Conclusion of calculations
If we use the above conditions, we can conclude that a 38 kW boiler will be required to heat the house. By calculating the power of a gas boiler in an individual house using this formula, you can get the exact figure.
Calculation of power depending on the volume of coolant
An important parameter in determining the power of the boiler is the volume of liquid that is in the heating system. It is designated as follows: V system. The calculation must be carried out using a ratio of 15 l / 1 kW. The formula will look like this: V syst=W cat x 15.
Calculation of power can be done by example. If the house is built in central Russia, and the area of \u200b\u200bthe room is 100 m22, then you will need to try to get the exact value of the boiler power. For this region, the specific power is from 1.2 to 1.5 kW. It is better to take the maximum value. This will allow you to calculate the power of the gas boiler relative to the volume of the coolant: W cat \u003d 100 x 1.5: 10 \u003d 15 kW; V syst can be calculated by multiplying 15 and 15, which will give 225 l.
The value from this example, which is 15 kW, will be the boiler output with a system volume of 225 liters. This suggests that inIn a room with an area of 100 m2 you will get a comfortable temperature even in the most severe frosts outside the window, which is true only if the house is located in the middle zone of the country. For other regions, the calculation will look different.
Types of boilers
The most optimal solution for efficient heating is a gas boiler. It is particularly suitable if there is no access to the central heating system. The demand for this equipment is explained by the type of fuel consumed. Natural gas is the most accessible resource. It is already known how to calculate the power of a gas heating boiler from the area. But when choosing such a device, it is also important to understand the types of boilers.
Classification can be made according to the method of execution. Models can be floor or wall. The first are distinguished by a wide range of power control. Such devices are suitable for buildings up to 200 m22. Wall-mounted boilers are more compact, which saves installation space. Such units have devices that ensure safe operation.
How to calculate the power of a gas boiler by area is already known. But besides this, it is also important to understand the types of boilers. They can also be divided into devices according to the number of circuits. Single-circuit units are intended only for heating the building, while installations with two circuits will provide space heating and supply warm water to the house.
On sale you can see boilers that differamong themselves also according to the method of discharge of combustion products. Boilers can have products removed by natural draft. Such equipment is installed in small houses and non-residential premises. There are also models with forced draft, which have a closed combustion chamber. They take in air through a coaxial chimney.
In conclusion
Calculation of the power of a heating gas boiler must be carried out before purchasing such equipment. If you don't, you run the risk of purchasing a device that will wear itself out or become a source of unforeseen expenses. Indeed, in the first case, insufficient power will not satisfy the needs of the residents of the house in the cold, therefore, you will have to turn on the equipment at full capacity.
