The calculation formula for the heating system

Having an effective heating system is essential for keeping our homes warm during the winter. However, how can we determine which kind or size of heating system is best for our home? That is why it is so important to understand the heating system calculation formula. Homeowners can ensure comfort and energy efficiency by making educated decisions about their heating needs by understanding the fundamentals of this formula.

Numerous variables, including the house’s size, insulation, climate, and even individual preferences, affect heating systems. But underlying all these systems is a simple idea: the quantity of heat required to keep an interior temperature comfortable. This is where the formula for calculation comes into play, acting as a guide to ascertain a home’s appropriate heating capacity.

The heating system calculation formula essentially considers a number of important variables. These include the building’s insulation quality, the intended indoor and outdoor temperatures, and the house’s square footage. Homeowners can calculate the number of British Thermal Units (BTUs) needed to properly heat their space by entering these variables into the formula.

Comprehending the computation formula enables homeowners to maximize the efficiency and economy of their heating systems. Homeowners can customize their heating solutions to fit the unique requirements of their home, as opposed to merely speculating or depending on antiquated technology. This helps save energy and reduce utility costs in addition to guaranteeing a comfortable living environment.

Examining the calculation formula is a useful step whether you’re thinking about replacing your old heating system or installing a new one. It enables you to collaborate closely with heating specialists, giving them the knowledge they need to create a system that satisfies your needs. Ultimately, homeowners can take charge of their indoor comfort and energy use by demystifying the intricacies of heating calculations.

Formula	Description
Heat Loss Calculation	Determine the rate at which heat is lost from the house, usually based on factors like insulation, outdoor temperature, and house size.
Heat Load Calculation	Calculate the amount of heat needed to maintain a comfortable temperature inside the house, considering factors like outdoor temperature, indoor temperature settings, and house size.

What is the calculations for

Centrifugal pumps are a common feature of modern autonomous heating systems that are used to regulate temperature in residential buildings. They allow the liquid in the heating circuit to circulate continuously.

The temperature of the water at the heating boiler’s output can be lowered by raising system pressure, which will lower the amount of gas the boiler uses on a daily basis.

When the circulation pump model is chosen carefully, it becomes possible to raise the equipment’s efficiency during the heating season and maintain a comfortable temperature throughout the building.

What you need to know to calculate power

In order to comprehend the algorithm used to calculate the circular pump itself, one must remove doubt from any parameter. In order to accomplish this, you must first locate the area of the property where the autonomous heating system is to be installed by opening its technical passport. For illustration, consider a 300 m² private home that is separate from other structures.

The identification of the values required for calculation will be the following stage.

You must ascertain the following three key parameters:

• QN – heat source power (kW);
• Qpu – productivity of the circulation pump, an indicator of the volumetric supply of the coolant for the type of premises we have chosen (m³/hour);
• HPU – the pressure of the pressure necessary to overcome the hydraulic resistance of the system (m).

Calculation of the power of the heat source (AOGV)

There are specific technical standards for the power of the heating source for each room, based on its size or volume.

Using the following formula, we will determine this parameter:

Sn × qud ÷ 1000 = Qn

The heat source’s power

Unique thermal requirements for the space

We are aware of the heated room’s area, which is 300 m². The second indicator is dependent on the kind of structure; in our case, which is a separate building, its value is 100 W/m²; if it is an apartment building, it is 70 W/m².

We’ll try our hand at the following values substitutions in the formula to see what works:

Thirty kW is 300 × 100 ÷ 1000.

Therefore, the heating system for our building had a power of 30 kW. There’s another way to figure this one out.

The following table shows the heated room’s volume and the heating unit’s power.

The property has a new house’s volume (m³).

Perforce me to remind you that the room’s volume is equal to the product of its area times its height.

• V is the volume of the room;
• S – heated area;
• h – room height.

In our instance, at the 2.5 m ceiling height, it will be:

The same 30 kW is what we get when we search for this indicator in the table’s second column.

The calculation of the performance of the pump

By accurately calculating the pump’s power, you can always supply a heating system with the necessary amount of coolant. Once the heating boiler’s technical specs have been established, you can compute how well the circulation system will function in our room.

The following formula will be applied:

Qpu = Qn ÷ kτ × δt

Power from heat source (AOGV)

The fluid’s heat capacity

The difference in temperature between the system’s input and output

Water has a specific heat capacity of 1.164 when used as a coolant. The value of this parameter needs to be found in the pertinent tables if a different liquid is being used.

The method of elementary subtraction of indicators removed from the measuring devices installed at the system’s input and output can be used to calculate the value of the temperature difference (δt) in a functioning heating system (δt = t1 – t2, where T1 is the temperature at the heating contour’s input and T2 is its output).

You’ll have to use standard indicators otherwise. The temperature differential (δt) between the system’s input and output varies between 10 and 20 °C.

Use the average value of -15 °C and enter the obtained values into the formula:

30 ÷ 1.163 × 15 = 1.72 m³/hour is Qpu.

Currently, one of the circulation pump’s technical characteristics is understood.

Calculation of the required power (height) pressure

After determining the coolant pressure needed to overcome the internal hydraulic resistance of the heating system’s pipes and components, which is dependent on the heating boiler’s power and the pump’s performance, comes the next step.

In order to achieve this, thermal losses are considered along the circuit’s longest cut, which runs from the heat source to the distant radiator. The pressure of the supplied fluid must be greater than the total hydraulic resistance of all heating devices in order to provide heat to any of its points.

The following formula is utilized to determine the heating pump’s pressure:

R × l × zf ÷ 10000 is Hpu.

Pressure and power (height)

Drops in the feed pipe and "Refunctions"

The heating circuit’s duration

Coefficient of Hydravel. resistance to the system’s shaped and locking reinforcement

The value of the parameter R ranges from 50 to 150 PA/m depending on the pipe diameter (the minimum indicator is applicable for water systems with a pipe diameter of 2 inches and above; losses are 150 PA/m for modern plastic and metal pipes). We have to use the maximum value for our room.

In cases where precisely determining the circuit length (l) proves to be challenging, the heated room’s dimensions are utilized to compute this parameter. The house’s length, width, and height indicators are folded, and then they are doubled. Assuming a 300 m² total area, the house’s dimensions are 30 m in length, 10 m in width, and 2.5 m in height. Here, l equals (30 + 10 + 2.5) × 2, or 85 meters.

The simplest way to find the ZF value is to use the following formula: 1.3 if there isn’t a thermostatic valve in the system, and 2.2 if one is.

To calculate, find this coefficient’s maximum value and enter all of the values you find into the following formula:

150 × 85 × 2.2 ÷ 10000 = 2.8 meters.

The computation method that is suggested is not the only one. There are formulas that account for the loss coefficient in order to determine the pump pressure more precisely, but the actual values of these indicators remain unchanged.

Hydraulic resistance

This phrase describes the system’s complete loss of pressure. Each component that makes up the heating circuit has a unique value for this attribute.

Among them are:

• valves;
• valves;
• filters;
• measuring and regulatory devices;
• radiators;
• convectors, etc. D.

The values listed in the technical documentation for each heating circuit component are used to precisely calculate the losses in the system.

In the event that this is not feasible, the data is listed in the following table:

In this instance, figuring out the pressure height using a marginally different formula is more practical.

Here, H is equal to 1.3 × (r1l1 + r2l2 + z1 + z2 +… + Zn) ÷ 10,000.

• R1, R2 – losses in the pipe of the feed and “return” (pa/m);
• L1, l2 – the length of the lines of the pipeline of the feed and “return” (m);
• Z1, z2 … zn – pressure losses on individual elements of the system (PA).

The coefficient of recalculation of the Pascal into meters is the number found in the denominator of the formula (10,000).

Choose a pump

Once all the requirements for purchasing the circulation pump have been established, you can begin selecting a particular model. The pressure height affixed to the device’s passport and the productivity schedules show the technical specifications of these kinds of devices. It’s easy to find this information online.

One, two, or three graphs are constructed in the coordinate system to show the point of the ideal ratio of these values, depending on the number of speeds. We defer the pump performance value along the X axis and the pressure height along the Y axis. The optimal combination of these parameters will occur when their intersection point is as close to the graph’s point as possible.

Three speeds are available in the most popular models. Should you halt at any of them, the characteristic selection process must be executed in accordance with the schedule that corresponds to the second speed—that is, the average. In other situations, any of them can use the combination of parameters.

The cost of various models of heating system pumps

Pump heating

How to calculate the pump if the power of the boiler is known

There are frequently instances where the pump is added to an existing heating system or where the boiler is purchased in advance. Since the heating unit’s power is known in this instance, the value of this indicator is used to select the other components of the circuit.

The following formula is used to determine the circulation pump’s performance given the heating source’s power.

N ÷ (t2 – t1) = Q, where

• Q is the performance of the pump (m³/hour);
• N – power of the heating device (W);
• T2 – the temperature of the coolant at the input of the system (⁰S);
• T1 – fluid temperature at the output of the contour (⁰S).

Use the average temperature difference of 15 °C if it is impossible to precisely ascertain the specified parameters of the presentation and "return".

The number of speeds in pumps

A circulating type pump is essentially an electric motor with an impeller shaft that is mechanically connected to it. From the working chamber, the pump’s blades expel heated liquid into the heating contour highway.

The pumps are separated into parts with a dry and wet rotor based on the level of contact with the coolant. While the latter pass the entire stream through themselves, the former only submerge the lower portion of the impeller in the water.

Although models with a dry rotor have higher efficiency, their noise level during operation causes several inconveniences. Although they operate more comfortably, their wet rotor equivalents are less effective.

In order to maintain different pressure levels in the heating system, modern circulation pumps can be run in two or three speed modes. By using this feature, the room can be quickly heated to its maximum speed, the ideal operating mode can be selected, and the device’s power consumption can be lowered to 50%.

The pump body is equipped with a unique lever that is used to change the speed. Certain models are equipped with an automated control system that modifies the engine rotation speed based on the temperature of the surrounding air in the heated room.

Useful recommendations

Structures with a "wet" rotor should be given preference when selecting a pump for a heating system because they operate more quietly and can support heavier loads than the hydraulic components of other modifications.

In light of this, consider the case material carefully; choose products made of brass, bronze, or stainless steel. Additionally, models with ceramic shafts and bearings should be preferred. These devices have a lifespan of more than 20 years.

Make sure the impeller shaft is positioned horizontally, or parallel to the pipe, when you install the device in the system. When a suspicious noise is heard while the pump is operating, it does not necessarily indicate that there is a malfunction or manufacturing defect. The amount of air in the system after starting should be reduced.

Maintaining efficiency and comfort in your home requires that you understand the formula used by your heating system. Understanding the basics of heat generation, distribution, and retention in your home will help you make well-informed decisions to maximize the efficiency of your heating system.

Finding out how much heat escapes your house is a crucial component of the calculation formula. This entails taking into account elements like building materials, windows, doors, and insulation levels. You can properly size your heating system to ensure that it is neither too small, which would result in insufficient heating, nor too large, which would result in energy waste, by accurately assessing the amount of heat loss.

Knowing the heat output of your heating system is another crucial element. This covers elements such as the fuel source, efficiency ratings, and kind of heating equipment utilized. You can maximize comfort and reduce energy use by adjusting the heat output of your system to the estimated heat loss of your house.

In addition, the calculation formula accounts for variables like occupancy patterns, thermostat settings, and variations in the outside temperature. By adjusting the heating system’s performance to your home’s unique requirements, these factors help maximize comfort and efficiency all year long.

To sum up, knowing how to calculate your heating system will enable you to make well-informed decisions that maximize comfort, minimize energy use, and protect the environment. No matter the outside weather, you can optimize your heating system to create a warm and comfortable home environment by knowing the principles behind heat generation, distribution, and retention.

Knowing your heating system’s calculation formula is crucial when it comes to insulation and heating for your house. The foundation of this formula helps homeowners choose the appropriate size and capacity for their heating system. Through the consideration of various factors like the area’s dimensions, insulation caliber, regional weather patterns, and preferred temperature, the formula offers a customized method for guaranteeing maximum comfort and effectiveness while reducing energy loss and expenses. Gaining knowledge of this formula enables homeowners to choose their heating systems wisely, creating a warm, inviting, and energy-efficient home.

Video on the topic

How to calculate the circulation pump for the heating system