Simplified methodology for calculating the heating system

Making sure your house is adequately heated as winter draws near is essential for both comfort and security. Because the process of optimizing or installing a new heating system often involves complex calculations, many homeowners find it intimidating. Even people without technical backgrounds can, however, make educated decisions about their home heating solutions with a simplified understanding of heating requirements and system sizing.

Making up for heat loss is the fundamental idea behind heating any given space. Every house loses heat at a different rate due to its distinct insulation and design. You can estimate how big the heating unit needs to be in order to keep the interior temperature comfortable using a simplified method for calculating the requirements for the heating system. This straightforward approach focuses on the essential elements such as the size of the area to be heated, the local climate, and the effectiveness of your home"s insulation.

We can divide the work into doable steps that most homeowners can accomplish by simplifying the calculation process. With the help of this guide, you can easily assess your heating requirements without becoming bogged down in the complex details of thermal dynamics. The intention is to give you the information you need to upgrade or select your heating system in an economical and efficient manner, so that your house is always a cozy and friendly retreat during the winter.

It’s crucial to use a simplified approach when designing a heating system for your house so that you can gauge your heating requirements without becoming bogged down in technical details. Using this method, you can determine how much heat escapes your home overall depending on its size, the quality of its insulation, and the climate where you live. You can calculate the heating system capacity needed to keep comfortable temperatures throughout the winter months by knowing these important factors. Homeowners can make more informed decisions about their heating systems thanks to this simplified computation, which improves energy efficiency and lowers costs.

We calculate the diameter of the pipe for heating, the diameter of the pipeline

Nuances

Pipe selection will vary between forced and natural circulation systems. The diameter of the pipes for the central system is determined based on the apartment heating systems. Additionally, when using autonomous, the diameter and volume of the pipe can be calculated; a different diameter may be possible depending on:

• pipe manufacturing material;
• type of circulation (carried out using a pump or natural circulation);
• water flow rate;
• water pressure;
• heating system wiring;
• Type of coolant.

Heat-transfer plastic pipes

The material selection is important in the first place when figuring out the diameter. Based on this standard, they differentiate:

• plastic pipes (differ in cheapness and ease of installation);
• steel or copper (high price, complex in installation);
• metal -plastic (internal wall of food polyethylene).

Heating steel pipes

Steel pipes are disappearing farther and farther into the distance.

Which size is better, the calculation of the pipe area

The recommended practice is to use the diameter of pipes that are commonly accepted in sizes; however, keep in mind that the thickness of the material may cause differences in the values provided by different manufacturers. The use of pipes with a large diameter is advised if the heating system is lengthy and has numerous branches and transitions because the larger the diameter, the more expensive the product.

The riser’s dimensions must also be considered. If you choose the pipe’s diameter incorrectly, you could accidentally turn off the heating system when it first starts up.

Heating pipes made of plastic and metal

The following guidelines should be followed when determining the diameter of heating pipes to use:

1. A very large diameter leads to low water pressure. If you use in a small house, then the circulation failure will entail a violation of the temperature regime.
2. Too small – contributes to the formation of high pressure and the appearance of noise.
3. In different situations, the deliberate use of a particular diameter of the pipes is necessary.

Calculation calculator of the pressure of the circulation pump

Poop calculation algorithm

The circulation device’s primary function is to move fluid along the contour. Nevertheless, different models may not be able to pass through the various volumes of the workplace, so special programs are frequently required for calculations.

The device needs to overcome the resistance offered by the pipelines’ surface in order to fulfill its intended function. Its parameters can vary greatly depending on the diameter and material of the elements. The parts of the valves that adjust and lock have a big influence on the pressure drop in addition to the pipelines themselves. When thermostatic devices are used to control the temperature regime, the strongest resistance is evident.

A pump is offered to guarantee circulation in the prescribed format.

It can be difficult to understand the hydraulic pressure loss calculation formulas. As a result, the program that is being presented offers a streamlined calculation algorithm. Ultimately, I am able to obtain the outcome, albeit with minor mistakes. There is an operational reserve for leveling them. Therefore, using these computations in practically any circumstance is quite real.

The source data can be entered into the calculator using just two fields. The first one ought to show how long the heating system’s pipelines are. It is required that the entire length of the vertical and horizontal sections be reflected. Because the reinforcement used provides a significant resistance, you must select the type of locking and adjusting devices in the second field. You must specify the point that works best for your heating system.

What are the requirements for the premises to be observed when installing the system

The best course of action during installation will be to install the pipeline at the beginning of the ceiling construction. This approach is 30–40% more cost-effective than using a radiator.

Although it is feasible to install a water heating structure in a finished room, it is important to consider the following requirements in order to save money for the family:

1. The height of the ceilings should allow mounting warm floors with a thickness of 8 to 20 centimeters.
2. The height of the doorways should not be less than 210 centimeters.
3. For installation of cement – sandy screed, the floor should be more durable.
4. In order to avoid the disgrace of contours and high hydraulic resistance, the surface for the base of the structure should be even and clean. The permissible uneven rate is not more than 5 millimeters.

Plastering and window installation should also be done in the building itself or in separate rooms where the heating system will be installed.

Calculation of the quantity and power of batteries

The efficiency of heating a given room is dependent on a number of factors, including the number of radiator sections, their design, the material from which they are made, their surface area, and the method by which they are connected to the main pipeline. Other factors include the insulation of the walls, the material of the walls, heat loss through windows, and other factors.

We’ll make use of the suggested information from specialized literature. For a brick house, 1 m3 needs about 0.034 kW of heat to keep it at a comfortable temperature; SIP panels provide 0.041 kW of heat in the house; insulated brick houses with overlapping, attic, loading walls, and foundation require 0.02 kW of heat.

Think about choosing batteries, for instance, for an 18 m2 room with a 2.5 m ceiling height. within a brick home. (0.0534 kW).

1. We find out the volume of the room: 18 x 2.5 = 45 m3.
2. We calculate how much thermal energy is needed for a given room: 45 x 0.034 = 1.53 kW

It is now necessary for you to use the table with the battery characteristics.

The primary features of the most popular radiators are depicted in the figure. The best balance between aluminum battery characteristics and cost, as indicated by the data presented. One section, whose lower boundary is 0.175 kW, needs data on its power.

1. Divide the result by the power of the section of the selected type of radiators and we get the number of sections: 1.53/ 0.175 = 8.74

In summary, we require an aluminum radiator with nine sections to heat a 45 m³ room. Make comparable estimates for every room in the house.

Hydraulic linking

Regulating and shut-off valves are used in the heating system to balance pressure drops.

The system’s hydraulic linking is predicated on:

• design load (mass flow rate of the coolant);
• data of pipes manufacturers by dynamic resistance;
• the number of local resistances in the area under consideration;
• technical characteristics of the reinforcement.

Each valve has its own installation characteristics, such as pressure drop, mount, and throughput. They calculate the coolant flow coefficients into each riser and subsequently into each device.

Measured in kilograms per hour, pressure losses are directly correlated with the coolant flow rate squared, where

S is the dynamic specific pressure work, expressed in PA/(kg/h), and the given coefficient is the site’s (hole’s) local resistance.

The total of all local system resistance is represented by the coefficient hole above.

Determination of the flow rate of the coolant and pipes diameters

Each heating branch must first be segmented into sections, beginning at the very end. The breakdown occurs in accordance with the water flow, which shifts from one radiator to another. Thus, a new section starts after every battery, as seen in the above-mentioned example. Starting at the first site, we focus on the power of the last heating device and discover there that the coolant is flowing at a massive rate:

• G – the flow rate of the coolant, kg/h;
• Q – thermal power of the radiator in the area, kW;
• Δt – temperature difference in the supply and reverse pipeline, usually take 20 ºС.

The coolant calculation for the first section looks like this:

86 kg/h = 860 x 2/20.

The outcome should be incorporated into the plan right away, but we will require it in liters per second for additional computations. You must apply the following formula to create a translation:

G /3600ρ = GV, where:

• GV – volumetric water consumption, l/sec;
• ρ – water density at a temperature of 60 ºС is 0.983 kg / liter.

These tables list the diameter values for both steel and plastic pipes based on the coolant’s flow rate and speed. The costs of l/s are shown in table 1 for steel pipes in the first column if you open page 31. To avoid doing a complete pipe calculation for a frequently used home’s heating system, simply select the diameter based on consumption, as illustrated in the figure below:

So, for our example, the internal size of the passage should be 10 mm. But since such pipes are not used in heating, we boldly accept the DN15 (15 mm) pipeline. We put it in the diagram and go to the second section. Since the next radiator has the same power, you do not need to use formulas, we take the previous water consumption and multiply it by 2 and we get 0.048 l/s. Again we turn to the table and find in it the nearest suitable value. At the same time, we do not forget to monitor the speed of the water flow V (m/s) so that it does not exceed the indicated limits (in the drawings it is marked in the left column with a red circle):

The DN15 pipe is also used to lay section No. 2, as shown in the figure. Next, we determine expense in section No. 3 using the first formula:

Transfer 860 x 1.5 / 20 = 65 kg / h to alternative units:

0.018 l/s = 65 /3600 x 0.983.

We turn back to the table and see that, after adding it to the total of the costs from the two previous sections, we get: 0.048 + 0.018 = 0.066 l/second. The DN15 pipe is appropriate for the coolant speed this time because our example only computes the pressure, not the gravitational system:

Following this path, we compute every area and utilize every piece of information on our axonometric scheme:

Calculation of the circulation pump

The goal of the coolant flow network’s pump selection and calculation is to determine the coolant’s pressure loss. The outcome will be a figure that illustrates the proper pressure that the circulation pump should produce in order to "push" water through the system. The following formula determines this pressure:

• P – pressure losses in the network of pipelines, PA;
• R – specific resistance to friction, pa/m;
• l is the length of the pipe in one section, m;
• Z – loss of pressure in local resistances, PA.

The Shevelev tables make it simple to find the RL value for each site, but this calculation is quite large and intricate. The values of 1000i are indicated in each section of the example by a blue circle; the pipe’s length is all that is needed to be counted. Consider the first section in the example; it is five meters long. The frictional resistance will then be:

13.1 bar is equal to 26.6 /1000 x 5.

Additionally, we miscalculate every component of a heating system that is passing, and we will then summarize the outcomes. The value of Z, the pressure differential in local resistance, needs to be determined. These numbers are listed in the product passport for the boiler and radiators. We recommend that you make all of these indicators and take 20% of the total friction loss (RL) for all other resistances. After multiplying the resultant value by the stock coefficient of 1.3, the required pump pressure is found.

You should be aware that the pump’s performance is determined by the total amount of water used by all of the risers and branches, not by the heating system’s capacity. A calculation example is given in the previous section; however, when choosing a pumping unit, a supply of at least 20% must also be provided.

The purpose and progress of the calculation

Naturally, you can use an online calculator—there are plenty available on the Internet—or speak with experts for the answers. However, the first is more expensive, and the second may yield an inaccurate result that still requires verification.

Therefore, it is best to exercise patience and focus on your own work. It is important to realize that, in order to select a circulation pump appropriately, the practical aim of hydraulic calculation is to select the passing sections of the pipes and calculate the pressure difference throughout the entire system.

This is how the general calculation scheme appears:

• Preparation of the axonometric scheme: when the calculation of heating devices has already been completed, their power is known, it must be applied to the drawing near each radiator;
• determination of the flow rate of the coolant and diameters of pipelines;
• calculation of the resistance of the system and the selection of the circulation pump;
• calculation of the volume of water in the system and the capacity of the expansion tank.

Any hydraulic calculation for the heating system starts with a three-dimensional scheme (axonometry) for clarity’s sake. It is applied to all known data. For illustration, consider a portion of the system depicted in the drawing:

Calculation of hydraulics of the water heating system

The coolant circulates based on the system’s pressure, which varies from time to time. Water friction forces against pipe walls and resistance on fittings and pipe fittings cause it to be reduced. The homeowner is also responsible for some of the heat distribution in each room.

When the coolant temperature rises, the pressure rises along with it, and when it falls, the pressure falls.

To prevent the heating system from being undermined, the environment must be such that each radiator receives the amount of coolant required to maintain a specific temperature and replace the heat that will inevitably escape.

Hydraulic calculation’s primary objective is to align estimated costs across the network with actual or operational costs.

As of this design phase,

• pipes diameter and their throughput;
• local pressure losses in certain sections of the heating system;
• hydraulic linking requirements;
• pressure losses throughout the system (general);
• The optimal flow rate of the coolant.

The following preparations must be completed in order to produce the hydraulic calculation:

1. Collect the initial data and systematize its.
2. Choose a calculation method.

The designer does the heat engineering calculation and looks at the object’s thermotechnical parameters first. This gives him knowledge of the required temperature in each room. The next step is to choose the heat source and heating appliances.

An illustration of a private home’s heating system schematic

The type of heating system and the features of its balancing, pipes, and reinforcement are chosen during the development stage. Finally, an axonometric wiring scheme is created, and the following premises are developed:

• capacity of radiators;
• coolant flow;
• arrangements of thermal equipment and pr.

Every system section and its nodal points are identified, computed, and applied to the ring drawing length.

Calculation of the diameter of the pipes

Based on the findings of the thermal calculation and supported by economic considerations, the cross section of the pipes should be calculated.

• for a two -pipe system – the difference between TR (hot coolant) and to (chilled – return);
• for one -pipe – the flow rate of the coolant G, kg/h.

Furthermore, consideration should be given to the working fluid’s (coolant’s) velocity, or v. Its ideal speed falls between 0.3 and 0.7 m/s. The relationship between the speed and the pipe’s internal diameter is inverse.

When the water’s speed reaches 0.6 m/s, a distinctive noise enters the system; if it falls below 0.2 m/s, air traffic jams could occur.

The rate of heat flow is an additional speed characteristic that will be needed for computations. It is represented by the letter Q, is expressed in terms of the quantity of heat transmitted per unit of time, and is measured in watts.

The parameters of the heating system, which include the length of each section and the devices connected to it, are needed in addition to the above initial data for calculation. For ease of use, this data can be condensed into a table, like the one below.

Table of the plots’ parameters

The designation of the site	Plot length in meters	The number of devices a section, pcs.
1-2	1.8	1
2-3	3.0	1
3-4	2.8	2
4-5	2.9	2

Utilizing the reference tables is simpler because calculating the pipe diameters is a complex process. They are available in SNiP, special literature, and the websites of pipe manufacturers.

When choosing pipe diameter, installers apply the rule that was developed through an extensive analysis of numerous heating systems. It’s true that only modest homes and apartments fall under this. The majority of heating boilers come with ¾ and ½ inch pipe and return pipe installed. This type of pipe and wiring is completed prior to the initial branching. The pipe size is further reduced by one step on each section.

If the house has two stories or more, this method is not justified. In this instance, it must contact the tables and perform a thorough calculation.

Scope of use of circulation pumps

The primary function of the circulation pump is to enhance coolant circulation in accordance with the heating system’s components. The issue of water that has already cooled entering heating radiators is a well-known concern for apartment building occupants on higher floors. The fact that the coolant in these systems flows very slowly and cools down until it reaches portions of the heating circuit at a considerable distance is related to similar situations.

The radiators located at the farthest points of the circuit may not heat at all, which can also be an issue when operating autonomous heating systems in suburban homes with naturally occurring water circulation. It is also a result of the coolant’s low pressure and sluggish passage through the pipeline. Avert similar circumstances when installing circulation pumping equipment in private homes as well as multi-unit buildings. These pumps force the necessary pressure to be created in the pipeline, delivering hot water at a high speed to even the heating system’s furthest points.

The pump makes the current heating more efficient and enables you to upgrade the system by adding more radiators or automation components.

When used to heat small-area houses, their efficacy as a heating system with naturally occurring fluid circulation that tolerates thermal energy is demonstrated. However, by adding a circulation pump to such systems, you can not only make them more efficient to use but also save money on heating since the boiler will use less energy.

By its constructive execution, the circulation pump is a motor whose shaft transfers rotation to the rotor. A wheel with shoulder blades is installed on the rotor – the impeller. Rotating the pumping chamber of the pump, the impeller pushes out the heated fluid in the injection line entering it, forming the flow of the coolant with the required pressure. Modern models of circulation pumps can work in several modes, creating various pressure of the coolant moving along them in heating systems. Such an option allows you to quickly warm up the house when the cold weather occurs, starting the pump to maximum power, and then, when a comfortable air temperature forms in the entire building, switch the device to an economical mode of operation.

Heating pump in a circular configuration

There are two main types of circulation pumps used in heating systems: those with "wet" and "dry" rotors. Only a portion of the rotor’s elements are in contact with the pumped environment in devices with a "dry" rotor, whereas all of the elements in first-type pumps are continuously in the coolant environment. While devices with a "wet" rotor produce the least amount of noise when in operation, pumps with a "dry" rotor are more efficient overall but also noise-producing when in operation.

Types of circulation pumps

A typical circulation pump’s design includes a ceramic rotor, a stainless steel case, and a shaft with a bladed wheel. An electric motor is used to drive the rotor. A comparable design allows water to be stamped on one side of the apparatus and then injected into pipelines via the exit. Water flows through the system as a result of centrifugal force. As a result, the resistance that develops in some heating pipe areas is removed.

There are two categories for these devices: dry and wet. The rotor and pumped water do not come into contact in the first instance. The electric motor’s working surface is fully polished, fitted together, and divided by unique protective rings. Although dry type pumps are thought to operate more effectively, they make a fair amount of noise when they’re working. For their installation, distinct, isolated rooms are furnished accordingly.

Consideration should be given to the existence of air turbulence generated during operation when selecting such models. They cause dust to rise into the air, which makes it easy for it to enter the device and cause the sealing rings to break. This will cause the system as a whole to fail. As a result, the thinnest water film serves as a barrier between the rings. It lubricates, preventing rings from wearing out too soon.

One characteristic that sets wet type circulation pumps apart is their rotor, which is always submerged in the liquid they are pumping. A sealed metal glass effectively separates the electric motor’s location. Small heating systems typically use these devices. They don’t need any additional maintenance and are far quieter when operating. These pumps are usually serviced on a regular basis and adjusted to the correct specifications.

These pumps have a low useful action efficiency as a result of the coolant sleeve’s insufficient tightness, which is a major drawback.

You should consider that the pump is a protected stator in addition to a wet rotor when selecting the model that you want.

Circulation pumps from recent generations are virtually entirely automated. By allowing for prompt switching of the windings’ level, smart automation greatly improves the device’s performance. These models are most frequently applied to water consumption that is constant or slightly variable. Step adjustment made it possible to select the best operating modes and save a significant amount of power.

Calculation of the volume of the expansion tank

You need to know how much coolant is in the heating circuit in order to figure out the volume of a membrane-style expansion tank. This is the dependency: 10% of the total amount of coolant should be in the expansion tank.

The following formula determines the amount of water in C: w = π (d2/4) l, where:

• π – 3.14;
• D is the inner diameter of the pipeline;
• L is the length of the pipeline section (if the entire circuit is made of a pipe of the same diameter, then we count the length of the circuit).

For instance, the reinforced polypropylene pipeline has an inner diameter of 21.2 mm, or 0.021 m, and a contour length of 100 m. 34.5 liters, or 3.14 x (0.0212/4) x 100, is equal to 0.0345M3. The conclusion drawn from this is that an expansion tank with a capacity of 3.5 liters is needed for the system, which has a coolant volume of 34.5 liters and operates within temperature and pressure limits of 0 to 80 °C and 1 bar, respectively.

You need information on the boiler’s power and the temperature differential at the boiler room’s input and output in order to calculate the circulation pump’s parameters. Then, you can use the formula Q = n /(t 2- T 1), where t2 is the temperature of the chilled coolant on the contour reverse branch and T1 is the coolant temperature on the supply pipe. Here, n represents the boiler unit’s power.

A word of advice: in addition to the data you have collected, you must compute the hydraulic resistances on equalizable bottoms and account for hydraulic losses at the pipeline’s points of narrowing, mud, and the reverse valve (if applicable) in order to construct a competent one-pipe heating system. The "hydraulic and thermal calculations" and "herz. C. O. WITH" programs are used to perform this calculation independently in a very straightforward manner.

Step	Description
1. Determine Building Size	Measure the total area of your home in square feet or meters. This will help estimate the heating power needed.
2. Assess Insulation Quality	Check the insulation levels in walls, roof, and floors. Better insulation reduces heating requirements.
3. Calculate Heat Loss	Estimate the rate at which heat is lost through doors, windows, and materials. This helps in deciding the capacity of the heating system.
4. Select Heating Method	Choose a heating system type (e.g., furnace, boiler, heat pump) based on efficiency, cost, and fuel type.
5. Estimate Fuel Consumption	Calculate the expected consumption of energy or fuel. This helps in planning operational costs.

Homeowners and contractors can create effective heating solutions with greater practicality thanks to the streamlined methodology for calculating heating systems. Through an emphasis on critical elements like room size, insulation level, and weather, this approach minimizes complexity without sacrificing precision. Simple math is used to quickly assess situations, which speeds up decision-making and the start of projects.

This method lowers the possibility of errors that could result from more intricate computations while also saving time. Homeowners can more easily discuss options with professionals when they have a better understanding of the heating needs of their spaces. In addition, this simplified process promotes the evaluation of economical and energy-efficient heating systems, which is in line with utility savings and environmental concerns.

In the end, using a more straightforward approach empowers people by deconstructing the process of calculating heating systems. In today’s energy-conscious world, it encourages a broader adoption of energy-efficient practices. In order to maintain efficiency and adhere to local standards, it will be crucial for users of this methodology to stay informed about any future changes in technology or laws.

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