Today, there are a lot of modern solutions for heating premises for various purposes. 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 make the choice of the unit for any room.
Why power is so important
Among the main features of a gas boiler, one should single out its power. For a correct definition, many factors should be considered. The life of the device, profitability, as well as the climate in the house will depend on how correctly you choose this parameter.
Why is power calculation necessary?
When choosing a gas boiler, you should be guided by measurements that allow you to understand what is the source of heat loss in the building. If you purchase a unit with excess power, this can cause unnecessary fuel consumption, therefore, unnecessary expenses. If the power is not large enough, this can damage the equipment, as he 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. She points out that for every 10 m 2 of housing, a kilowatt of power is needed. About 15% should be added to this value. From a simple formula it follows that if you have a house with an area of ββ100 m 2 , you will need a 12 kW boiler.
What is important to pay attention to
However, this approach is crude, and it 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. Practice shows that not all private houses are suitable for these criteria.
Power determination
Calculation of the power of a gas boiler can be carried out on 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 area of ββconstruction and the specific power of the boiler, which will be denoted by the abbreviation UMK. This value will vary and depends 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 suburbs, 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 = S x UMK: 10. It is true for a typical one-story or two-story house.
Calculation by example
As an example, consider a house with an area of ββ80 m 2 . If it is built in the northern region, then you can get the following calculations: 80 x 2: 10, which is 16. The figure determines the capacity of the boiler that you should purchase. If you choose a double-circuit boiler, which performs the function of not only heating the housing, but also heating the water, 20% should be added to the resulting formula.
What heat losses should be considered when calculating power
A complete picture cannot be obtained even if we take into account the climatic zone in which the house is built. Someone had double glazed plastic windows, and someone did not change the old wooden frames. Other homeowners have insulated exterior walls, while other homeowners have housing where a single layer of brick separates the street and the room.
If you use the averaged data, which are based on the calculations of specialists, the most impressive heat loss occurs on insulated walls. About 35 percent of the heat goes through them. Somewhat less (25%) is lost due to a poorly insulated roof. Ideally, there should be a warm attic above the house. But if the floor is poorly insulated, then heat loss will be about 15%. The same amount of heat goes through old wooden windows. We should not forget about the ventilation system, as well as about open windows, which account for about 15% of heat loss. As a result, the calculation of the power of the gas boiler, which is presented above, is not suitable for every residential building. For such cases, you should use your own counting system.
Power calculation based on dissipation factor
One of the important factors of heat transfer between the environment and the apartment building is the dispersion coefficient. Depending on how well the building is insulated, indicators should be used 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 dispersion coefficient will vary from 3 to 4. Most often these are temporary shelters made of wood or corrugated iron.
When calculating the power of a gas boiler for heating, a coefficient of 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 that are built in one brick. Instead of windows, usually wooden frames, and on top 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, facade thermal insulation or double masonry, as well as an insulated roof or attic.
The dispersion 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, and good windows are installed. Typically, such buildings have a good ventilation system. In this case, the dispersion coefficient will be the lowest - from 0.6 to 0.9.
When calculating the power of a gas boiler for a house using a formula in which there is a value of the dispersion coefficient, you will get the most accurate numbers for a particular structure. The formula is: QT = V x Pt x k: 860. Here, the value of QT 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 temperature in the room, subtract the minimum temperature that may be outside the window. The dispersion 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. In the example, a house with a volume of 300 m 3 will be considered. The level of heat loss here will be average, and the desired indoor air temperature is +20 Λ. The minimum winter temperature is -20 Λ. The calculation of the level of heat loss will look like this: 300 x 48 x 1.9: 860 β 31.81. If you know this figure, you can calculate how much power the boiler will perform its task. For this, the heat loss value must be multiplied by the safety factor, which usually varies from 1.15 to 1.2. These are the same 15-20 percent. The result is: 31.81 x 1.2 = 38.172. The number can be rounded down, which allows you to get the desired number.
Conclusion on the calculations
If we use the conditions specified above, we can conclude that for heating the house you need a boiler with a capacity of 38 kW. By calculating the power of a gas boiler in an individual house according to 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 syst. The calculation must be carried out using a ratio of 15 l / 1 kW. The formula will be as follows: V syst = W cat x 15.
Calculation of power can be carried out by example. If the house is built in the middle zone of Russia, and the room area is 100 m 2 , then you will need to try to get the exact value of the boiler power. For this region, the specific power ranges from 1.2 to 1.5 kW. It is better to take the maximum value. This will allow calculating the power of the gas boiler relative to the volume of the coolant: W cat = 100 x 1.5: 10 = 15 kW; V sist can be calculated by multiplying 15 and 15, which will produce 225 liters.
The value from this example, which is 15 kW, will be the power of the boiler with a system volume of 225 liters. This suggests that in a room with an area of ββ100 m 2 you will get a comfortable temperature even in the most severe frosts outside the window, which is only true if the house is in the middle lane 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 especially suitable if there is no access to a centralized heating system. Demand for this equipment is explained by the type of fuel consumed. Natural gas is the most affordable resource. It is already known how to calculate the capacity 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 by way of execution. Models can be floor or wall. The former are distinguished by a wide range of power regulation. Such devices are suitable for buildings up to 200 m 2 . Wall-mounted boilers are more compact, which saves installation space. Such units have devices that ensure safe operation.
How to calculate the capacity of a gas boiler by area is already known. But in addition to this, it is important to understand the types of boilers. They can also be divided into devices by the number of circuits. Single-circuit are intended only for heating the building, while installations with two circuits will provide heating of the premises and supply warm water to the house.
On sale you can see boilers that differ from each other in the way they discharge combustion products. Boilers may have a product outlet carried out by natural draft. Such equipment is installed in small houses and non-residential premises. There are also forced draft models that have a closed combustion chamber. They take in air through a coaxial chimney.
Finally
Calculation of the power of a heating gas boiler must be done before purchasing such equipment. If this is not done, you risk acquiring a device that will run for wear 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, it will be necessary to turn on the equipment at full capacity.