Calculation of the power of the heating boiler

Selecting the ideal heating boiler for your house is an important choice that will have a big impact on both your comfort level and energy costs. A warm and comfortable home is largely dependent on the power of your heating boiler, particularly in the winter. To guarantee effective heating and top performance, it is crucial to know how to calculate the heating boiler’s power.

There are a number of factors that affect how powerful your heating boiler is. The size of your house is one of the most important factors. Larger homes typically need stronger boilers in order to heat every room to a suitable temperature. But the computation is also affected by variables like the quantity of windows and doors, ceiling height, and the caliber of the insulation.

The climate where you live is another crucial thing to think about. Houses in colder climates will use more energy for heating than those in milder climates. When determining the boiler’s power, it is imperative to consider both the average outdoor temperature and the length of the heating season.

Furthermore, the kind of fuel your boiler burns will affect how much power it produces. Every fuel type, whether it be electric, biomass, gas, or oil, has a varying heating capacity and efficiency level. Accurately estimating the power needs of your heating system requires an understanding of the energy output of the fuel source you have chosen.

Precise measurements, mathematical formulas, and careful consideration of numerous variables are all used to calculate your heating boiler’s power. You can make sure that your heating system is the right size to meet your comfort needs while maximizing energy efficiency and minimizing operating costs by taking into account factors like home size, climate, insulation, and fuel type.

Calculation of the power of the heating boiler by area

The area of the premises is sufficient for an approximative evaluation of the necessary performance of the thermal unit. In its most basic form, 1kW of power is thought to be able to heat 10m 2 areas in central Russia. A house measuring 160 square meters will require a 16 kW boiler to heat it.

Because the climate and ceiling heights are not taken into consideration, these calculations are approximations. In order to achieve this, experimentally displayed coefficients are used, and the necessary adjustments are made.

For 10m2, the recommended standard is 1 kW, which is appropriate for 2.5–2.7 m ceilings. You must compute the coefficients and recount if the room above has ceilings. In order to do this, we calculate the correction factor by dividing the height of your property by the standard 2.7 meters.

The simplest method is to calculate the heating boiler power by area.

For instance, the ceiling height is 3.2 meters. We calculate the coefficient and round to 1.2 (3.2 m/2.7 m = 1.18). It turns out that a heating boiler with a capacity of 16 kW*1.2 = 19.2 kW is needed to heat a room that is 160 m³ and has a ceiling height of 3.2 m. Typically, they go in a bigger direction, or 20 kW.

Prefabricated coefficients are used to account for climate characteristics. Regarding Russia, they are:

• 1.5-2.0 for the northern regions;
• 1.2-1.5 for the regions near Moscow;
• 1.0-1.2 for the middle strip;
• 0.7-0.9 for the southern regions.

If the house is in the middle lane, a little south of Moscow, a coefficient of 1.2 (20 kW*1.2 = 24kW) is used, if in the south of Russia in the Krasnodar Territory, for example, a coefficient of 0.8, that is, the power is required (20 kW*0 , 8 = 16 kW).

The calculation of heating and boiler selection are crucial steps. You may obtain such a result if you locate power incorrectly.

These are the primary considerations that must be made. However, if the boiler is used primarily for heating, the results are reasonable. Add 20–25% to the estimated amount if heating water is also required. Then, to reach the highest winter temperatures, you must add a "stock." This represents an additional 10%. Total amount received:

• For heating a house and DHW in a middle lane 24kW+20%= 28.8 kW. Then the supply for the cold – 28.8 kW+10%= 31.68kW. Round and get 32kW. When compared with the initial figure of 16 kW, the difference is twice.
• House in the Krasnodar Territory. Add power for heating hot water: 16 kW+20%= 19.2 kW. Now the "reserve" in the cold is 19.2+10%= 21.12kW. Jacket: 22kW. The difference is not so striking, but also quite decent.

The examples demonstrate that these values at the very least need to be considered. However, it is evident that there should be a difference when calculating the boiler’s power for the house and the apartment. Using the coefficients for every factor, you can proceed in the same manner. However, there’s a more straightforward method that lets you adjust one thing at a time.

A coefficient of 1.5 is used to determine the house’s heating boiler. He considers the possibility of heat loss via the foundation, floor, and roof. Fair with the typical (average) level of wall insulation; two bricks or comparable in terms of the properties of the building materials.

For apartments, different coefficients are employed. In the event that an unheated attic has a coefficient of 1.0 and a heated room (or other apartment) has a coefficient of 0.7 on top. To obtain a reasonably accurate figure, you must multiply the boiler’s capacity using one of these coefficients in accordance with the above methodology.

To illustrate the calculation process, we will compute the gas boiler power for a 65-square-meter apartment with 3-meter ceilings situated in the center of the Russian Federation.

1. Determine the required power by area: 65m 2 /10m 2 = 6.5 kW.
2. We make an amendment to the region: 6.5 kW*1.2 = 7.8 kW.
3. The boiler will warm the water, therefore add 25% (we love the hotter) 7.8 kW*1.25 = 9.75kW.
4. Add 10% to the cold: 7.95kW*1.1 = 10.725KW.

We now round the result to obtain 11kW.

For the selection of heating boilers on any fuel type, the given algorithm is equitable. The formula for calculating the power of an electric heating boiler is the same as the formula for a solid fuel, gas, or liquid fuel boiler. The boiler’s output and efficiency are what matter most, and the type of boiler has no bearing on heat loss. The question at hand is how to use fewer energy carriers. And here’s where insulation comes in.

Power of the boiler for apartments

You can use SNiP norms to calculate heating equipment for apartments. Utilizing these guidelines is also known as calculating the boiler’s power by volume. In typical buildings, SNiP determines the necessary amount of heat to heat one cubic meter of air:

• The heating of 1m 3 in the panel house requires 41W;
• In a brick house on M 3, 34W is 34W.

With the apartment’s size and ceiling height known, you can calculate the volume. Next, multiply the volume by the norm to determine the boiler’s power.

The kind of fuel used has no bearing on how much power the boiler can produce.

For instance, we figure out how much power the boiler needs for 74 m^2 of rooms in a brick home with 2.7 m ceilings.

1. We calculate the volume: 74m 2 *2.7m = 199.8m 3
2. We think by the norm how much heat will be needed: 199.8*34W = 6793W. We round and transfer to kilowatts, we get 7kW. This will be the necessary power, which the heat unit must issue.

The power for the same room in the panel house can be easily calculated: 199.8*41W = 8191W. Although, in theory, they always round up more in heat engineering, you can consider your windows’ glazing. You can round the smaller windows if they have energy-efficient double-glazed windows. We think the double-glazed windows are good, and the 8 kW is enough.

The type of building determines the boiler power to use; less heat is needed for brick heating than for panel heating.

Next, you must account for the area and the requirement to heat the water when making calculations for the house. The modification of unusually low temperatures. However, the arrangement of the rooms and the number of stories are crucial factors in apartments. You must consider the walls that lead outside:

• One outer wall – 1.1
• Two – 1.2
• Three – 1.3

When selecting a heating method, you can rely on a reasonably accurate value that you will obtain after accounting for all the coefficients. It needs to be ordered in a profile organization if you want an accurate heat engineering calculation.

There is another method: to determine the real losses using a thermal imager – a modern device, which will show the places through which heat leaks go more intensively. At the same time, you can eliminate these problems and improve thermal insulation. And the third option is to use the calculator program that will consider everything instead of you. You just need to choose and/or put down the required data. At the output, get the calculated power of the boiler. True, there is a certain share of risk: it is not clear how true algorithms are the basis of such a program. So after all, you still have to at least approximately calculate to compare the results.

This is how the thermal imager appears in an image.

We hope that you now know how to figure out the boiler’s power. And you are not perplexed by the fact that this is a gas boiler. not dense fuel, or the opposite.

You can stop heat leaks based on the examination’s findings.

Articles about choosing pipes for the heating system and calculating radiator power might be of interest to you. Watch a video to get a general idea of common mistakes that are made when designing a heating system.

How to calculate the power of the boiler in the water heating system

One of the most important and costly features of any private home is autonomous heating. It depends on the type of heating system that the calculations determine, how well it will function, how much heat it will produce, and how much money will be needed for maintenance while the system is in use.

Diagram for installing an electric boiler.

Private homes are heated by boilers in heating systems that run on different fuels.

But regardless of the type of boiler, the power of the heating system is determined using a standard formula that applies to all systems:

• WKOT – the power of the boiler in kilowatts;
• S is the total area of all heated premises of the house in square meters;
• Wood – the specific power of the boiler necessary for heating ten square meters of the area of the room. The calculation is made taking into account the climatic zone in which the region is located.

Gas boiler on the wall.

The following power values are used in the calculation for the Russian regions:

• for areas of the northern part of the country and Siberia WUD = 1.5-2 kW for every 10 m²;
• For the middle strip, 1.2-1.5 kW is required;
• For the southern areas, the boiler power is sufficient at 0.7-0.9 kW.

The volume of fluid in the heating system is a crucial factor to consider when determining the boiler’s power. Traditionally, it is referred to as follows: System volume, or Vsist. The ratio used in the calculation is 15l/1kW. The formula’s perspective is as follows:

WKOT X 15 = Vsist The area of the room is 100 m², and the region is the middle strip of Russia when calculating the boiler power in the example.

It is well known that the specific power for this area should be between 1.2 and 1.5 kW. Consider 1.5 kW as the maximum value.

This gives us the precise value of the boiler’s power and the system’s volume:

• WKOT = 100 x 1.5. 10 = 15 kW;
• Vsist = 15 x 15 = 225 l.

If the room is in the middle lane of the country, the boiler’s power of 15 kW, obtained in this example, with its 225-liter system volume, ensures a comfortable temperature in a 100-square-meter space even during the harshest frosts.

Varieties of heating systems If the coolant is water, then it belongs to water heating systems, which is what the calculation was done for, regardless of the type of boiler used for heating. They are further separated into systems that have both forced and natural water circulation.

Heating system that uses the flow of water naturally

Diagram of a liquid fuel boiler.

The fundamental working principle of the system is predicated on the physical distinctions between hot and cold water. By utilizing these variations, heat is transferred from the boiler to the radiators by means of the movement of water within the pipes.

A vertical pipe known as the main riser carries hot water rising from the boiler. The pipe wiring splits off from it and travels through the highways. Additionally through fallers (risers), but the motion is downward. Heat is produced when water from falling risers flows through radiators. It gets heavier as a result of cooling, and because the pipes are wired backwards, it enters the boiler once more, heats up, and the cycle is repeated.

Water flows through the system continuously when the boiler is operating. The process of water expanding when heated lowers its mass and density, creating hydrostatic pressure within the system. When water is heated to 95°C, it becomes much lighter; one cubic meter will weigh 962 kg.At 40°C, the mass of water in one cubic meter is 992.24 kg. The water circulates as a result of the density difference.

A centrifugal pump is produced by the increased circulation pressure found in forced water circulation heating systems. Pumps are usually installed on the line that returns the cooled, worked-out coolant to the heating boiler. A functioning pump creates a lot more pressure in the pipes than does a system with natural circulation. As a result, the system’s water can flow in both horizontal and vertical directions.

The expansion tank has a unique connection. It is connected to the primary riser in systems that have natural circulation. The connection point for forced circulation is in front of the pump. An expansion tank that is carried above the heating system’s highest point is connected to this point via a unique riser.

A comparative evaluation of water heating systems’ boilers

Fuel boiler circuit.

Boilers that run on different fuel types and produce different amounts of heat are used in water heating systems. The most typical fuel kinds used in boilers are:

• electricity;
• gas;
• liquid: fuel oil, diesel fuel (diesel fuel);
• solid fuel: coal, firewood, pressed briquettes, granules from woodworking waste, other combustible materials.

Certain boilers are multipurpose and can operate on a variety of energy sources. Fuel, for instance, both liquid and solid.

Electric boilers are very convenient, but they are rarely used for complete heating. They are employed as backup or room-specific heaters. The power of electric boards that are sold does not exceed 15 kW. Using electricity to heat a home is too costly. According to the heating boiler’s power calculation, which was provided above, this is sufficient to heat a home with a maximum total area of 100 m².

Installing boilers of this type in large-living houses with a connected gas supply trunk pipeline is made possible by the relatively low cost of gas fuel. They are very convenient to use.

Regarding liquid fuel Even though the cost of liquid fuel is always rising, it is still roughly twice as expensive as electricity. Types of liquid fuel produce heat well. A 300 m³ residential building will require about 3 tons of fuel to heat each season. While using such boilers is advised, extra caution must be taken when using them.

Solid fuel needs to be constantly supervised. Boilers that automatically supply granular fuel from a bunker and have sophisticated systems in place to monitor temperature, combustion speed, and power parameters are an exception. It is profitable to use in the nation’s coal-producing regions where solid fuel is readily available at low cost.

Boilers that are combined and capable of using different fuels. Certain models run on solid, liquid, or gaseous fuel. A minor reconfiguration is typically necessary when moving from gas fuel to liquid fuel: changing the burner.

Power of the heating boiler: meaning and calculation

Calculation parameters. What needs to be taken into account

To begin with, though, let’s explore the significance of this value in general as well as, crucially, the reasons behind it.

The performance of a thermal generator, which can run on any kind of fuel, is essentially indicated by the characteristic that is described; that is, the heating contour and the area of the room that the generator can heat.

For instance, a heating system with a power of 3 to 5 kW can typically "cover" a house up to 50 kV m in area as well as a one- or two-room apartment with heat. Seven to ten kW of installation will "pull" for three-room homes with up to 100 kV of space.

Stated differently, their typical power consumption is one-tenth of the total heat area (measured in kW). However, this is limited to the broadest scenario. It takes computation to get a particular value. Various factors ought to be considered in the computations. Let’s enumerate them:

• Total heated area.
• The region where the calculated heating is valid.
• Walls of the house, their thermal insulation.
• Heat loss of the roof.
• The type of fuel of the boiler.

We will now discuss how power is calculated for the various types of boilers, including gas, electric, and solid fuel.

Gas boilers

Based on the aforementioned, a single, fairly straightforward formula is used to determine the power of boiler equipment used for heating:

S x n u. / 10 = N boiler.

Values in this case interpreted as follows:

• N boiler – the power of this particular unit;
• S is the full amount of the areas of all premises heated by the system;
• N u. – the specific value of the thermal generator, required for warming up 10 kV. m. The area of the room.

The climate zone—the area in which this equipment is used—is one of the primary determining factors for calculations. In other words, a solid-fuel boiler’s power is determined by taking into account certain weather conditions.

It is noteworthy that, although 1 kW was formerly thought to be equivalent to 10 kV meters during the time of the still-in-use Soviet heating unit power rates, it is now vitally important to accurately calculate for actual conditions.

You must take the following values, n u, in this situation.

• N u. = 1.7 – 1.8 kW per 10 kV. meters of square – for areas of the north and Siberia.
• N u. = 1.3 – 1.5 kW per 10 kV. meters of area – for areas of the middle lane.
• N u. = 0.7 – 0.8 kW per 10 kV. meters of square – for southern areas.

We will, for instance, compute a solid-fuel heating boiler’s power in relation to the Siberian region, where winter frosts can occasionally drop as low as -35 degrees Celsius. Let n u = 1.8 kW. Next, for heating a 100 kV-m-square-foot house. An installation containing a feature of the following computed value is required:

1.8 / 10 x 100 kV m. x N boiler = 18 kW.

As you can see, there is no force associated with the roughly one to ten kilowatt-to-area ratio.

It’s critical to understand! It is possible to determine the coolant volume, or the volume of water required to fill the system, if the number of kilowatts at a specific solid fuel installation is known. It only takes multiplying the received N heat generator by 15 to accomplish this.

The amount of water in the heating system in our instance is 18 x 15 = 270 liters.

However, there are situations in which accounting for the climate factor alone is insufficient to determine the heat generator’s power characteristic. It is important to keep in mind that certain aspects of the building’s design may contribute to heat loss. You must first take into account what the dwelling’s walls are. The degree of insulation in the home is a crucial consideration. It’s crucial to take the roof’s structure into account.

A wooden home with a gas boiler

Generally speaking, you can multiply the power that our formula yields by a unique coefficient.

The values of this coefficient are quite close:

• K = 1, if the house is more than 15 years, and the walls are made of brick, foam blocks or wood, and the walls are insulated;
• K = 1.5, if the walls are not insulated;
• K = 1.8, if, in addition to unleven walls, the house has a bad roof that passes heat;
• K = 0.6 with a modern house with insulation.

Assume that the house in our scenario is 20 years old, made of brick, and has adequate insulation. The power determined in our example then stays the same:

18×1 – N boiler = 18 kW.

Here, a coefficient of this kind needs to be considered if the boiler is installed in the apartment. However, if the apartment is not on the first or last floor, it will be 0.7 for a regular apartment. You should accept K = 1.1 if the apartment is on the first or upper floor.

Proceed to the analysis of the case involving an alternative fuel type.

In figuring out the power of your home heating boiler, you"re essentially determining how much heat your boiler needs to generate to keep your house warm and cozy. It"s crucial to get this right to ensure your home stays comfortable without wasting energy or money. To calculate the boiler"s power, you"ll need to consider factors like the size of your home, its insulation quality, the climate in your area, and the desired indoor temperature. By taking these factors into account, you can accurately size your boiler to meet your heating needs efficiently. Investing time in this calculation upfront can lead to significant savings in the long run by avoiding over- or under-sizing your boiler, which can result in higher energy bills or inadequate heating.

How to calculate the power for electric boilers

Rarely are electric boilers used for heating. The primary cause is the high cost of electricity in today’s world combined with the low maximum power of these installations. In addition, there’s a chance of network malfunctions and extended power outages.

The same formula can be used to calculate this amount as well:

S x N u = N boiler. / 10,

The resultant indicator should then be multiplied by the required coefficients, which we have already discussed in our writing.

But in this instance, there’s another, more precise approach. We’ll make that clear.

The foundation of this approach is the fact that 40 watts was initially taken. This figure indicates that heating 1 m3 requires a significant amount of power, without accounting for other factors. Additionally, the computation is performed in this manner. You must add 100 watts to each window and 200 watts to the door because windows and doors are sources of heat loss.

The same coefficients that were previously mentioned are considered at the final stage.

For instance, use this method to determine the power of an electric boiler placed in an 80 m³ home with a 3 m ceiling, five windows, and one door.

N boiler is equal to 40 x 80 x 3 + 500 + 200 = 10300 watts, or roughly 10 kW.

If the computation is performed for a third-floor apartment, the resultant value must be multiplied by a reducing coefficient, as previously indicated. Boiler = 10×0.7 = 7 kW in that case.

Let’s now discuss solid fuel boilers.

For solid fuel

As implied by the name, this kind of equipment heats with hard fuel. These units have clear benefits, particularly in rural communities and isolated settlements without gas pipelines. Typically, solid fuel in the form of pressed chips is firewood or pellets.

The methodology used to determine the power of solid-fuel boilers is the same as that of gas heating boilers mentioned above. Stated differently, the computation is performed using the following formula:

S x n u. / 10 = N boiler.

This formula is used to calculate the power indicator, which is then multiplied by the coefficients mentioned above.

But in this instance, it’s important to consider that a solid fuel boiler has a low efficiency. Therefore, a power supply of roughly 20% should be added after computing using the method described. On the other hand, you can leave the calculated value if a heat accumulator—a container meant to hold coolant—is going to be used in the heating system.

Illustration of a calculated-power solid fuel boiler

Factor	Description
House Size	The total area of your house in square feet or square meters.
Insulation Quality	The level of insulation your house has, ranging from poor to excellent.
Climate	The average temperature in your area during the coldest months of the year.
Windows and Doors	The number, size, and quality of windows and doors in your house.

One of the most important steps in making sure your home’s heating system is efficient and comfortable is figuring out how powerful your heating boiler is. You can prevent problems such as insufficient heating during cold spells or excessive energy consumption by precisely calculating the necessary boiler power.

The size and design of your house are important factors to take into account when figuring out boiler power. Greater boiler power is typically needed in larger homes with more floors and rooms in order to properly distribute heat throughout the area. In a similar vein, the quantity of heat required can also be affected by variables like insulation levels and ceiling height.

The climate where your house is located is another crucial factor to take into account. Naturally, colder climates will demand a higher boiler power to keep interior temperatures comfortable, particularly in the winter. When estimating the power needs for your boiler, it is imperative to take these regional climate variations into consideration.

Additionally, boiler power is largely dependent on the kind of heating system you have installed. For example, because radiant heating systems distribute heat more effectively than forced-air systems, they may use less electricity. It is necessary to comprehend the intricacies of your heating system in order to compute boiler power precisely.

Finally, when estimating boiler power, it’s critical to account for any upcoming home additions or remodels. Increased insulation or the addition of more rooms may affect your home’s overall heat needs, requiring changes to the power rating of your boiler.

To sum up, determining your heating boiler’s power accurately is crucial to keeping your house cozy and energy-efficient. You can make sure that your boiler is appropriately sized to meet your heating needs while minimizing energy waste by taking into account factors like home size, climate, type of heating system, and upcoming renovations.

Video on the topic

Choosing the power of the heating boiler. Mistakes and tips.

Calculation of the power of the heating boiler

Calculation of the power of the boiler / dependence on the volume of the room