What are heat pumps?

Heat pumps are innovative heating and cooling systems that transfer heat from one environment to another using a minimal amount of electricity. These devices work on the principle of energy transfer rather than energy production, making them a highly efficient and environmentally friendly solution for ensuring comfortable indoor temperatures. The main function of heat pumps is to extract heat from the external environment (air, water or ground) and transfer it to the building’s heating or hot water system. In summer, the heat pump can operate in cooling mode, removing excess heat from the room to the outside.

What are heat pumps?

The history of heat pump development dates back to the 19th century when the foundations of thermodynamics were laid and the first principles of heat transfer were studied. However, these devices were widely used only in the middle of the 20th century, when interest in energy-saving technologies increased. Since then, heat pump technology has evolved considerably, becoming more efficient, reliable and accessible to a wide range of consumers. Modern heat pumps can operate efficiently even at low ambient temperatures, providing stable and economical heating and cooling of buildings for various purposes.

Heat pumps are thus a key element of modern energy-saving systems, enabling significant reductions in heating and cooling costs, while reducing harmful emissions and contributing to the preservation of the environment.

Principle of operation of heat pumps

The operation process of a heat pump starts by extracting low-potential heat energy from the environment using an evaporator. This energy is transferred to a working fluid (most often environmentally friendly Freon), which is converted to a gaseous state at low pressure. The compressor then increases the pressure and temperature of the gas before it enters the condenser. In the condenser, the gas gives up heat to the heating or hot water system of the building, condenses and changes back to a liquid state. After that, through the thermostatic control valve, the working body returns to the evaporator and the cycle repeats.

Heat pumps can operate in different modes, providing not only heating in the cold season, but also cooling in the summer. In addition, they are able to prepare hot water for domestic needs. This is achieved through a reversible mechanism that allows changing the direction of the working body flow in the system, adapting the device to the current needs for heat or cold.

The use of heat pumps can significantly reduce energy consumption and ecological footprint, making them an ideal solution for today’s energy-efficient and sustainable homes and buildings.

Types of heat pumps and their applications

Heat pumps are high-tech devices that can provide both heating and cooling of rooms using energy from the environment. They are divided into several types depending on the source of energy and the way it is transmitted.

Air-to-water heat pumps

Air-to-water heat pumps are one of the most common because they do not require complex excavation work for installation. They extract heat from the outside air and transfer it to the building’s heating and hot water system. These pumps are efficient even at low air temperatures, but their efficiency may decrease at extremely low temperatures. These pumps are easy to install and have a wide range of applications, being suitable for both new and modernized buildings.

Ground-to-water heat pumps

Earth-to-water heat pumps utilize heat stored in the ground. Their installation requires drilling or laying horizontal circuits in the ground. These pumps provide high efficiency all year round because the ground temperature remains relatively stable at a certain depth.

Water-to-water heat pumps

Water-to-water heat pumps operate by utilizing the heat of groundwater. This type of pump requires a body of water or drilling capability. Despite high initial costs and permit complexities, water-to-water pumps offer one of the highest efficiencies of any heat pump type.

Each of these types has its application depending on local conditions, resource availability and specific heating and cooling system requirements. Selecting the best type of heat pump requires careful analysis and professional judgment, taking into account both the initial investment and the long-term savings in heating and cooling costs.

Comparative analysis and suitable application conditions. The choice of heat pump type depends on many factors, including climatic conditions, availability of natural resources (air, ground, water) and site specifics. Air-to-water heat pumps are suitable for most conditions and provide a versatile solution. Ground-to-water and water-to-water heat pumps require a larger initial investment but offer higher efficiency and may be the preferred choice in the long term, especially in colder climate regions.

Advantages and disadvantages of using heat pumps


  1. Energy savings and cost reduction. Heat pumps use natural resources (air, water, ground) as a source of energy, which reduces the consumption of traditional energy carriers and, consequently, reduces operating costs. According to studies, the payback period for such systems is between 2.5 and 5 years, which makes them a profitable investment in the long term.
  2. Environmentally friendly and durable. Heat pumps significantly reduce carbon dioxide emissions compared to conventional heating systems, contributing to the fight against global warming. In addition, they are highly durable and reliable, ensuring stable operation for many years.


  1. Possible limitations and efficiency conditions. Despite the wide range of benefits, heat pumps may not be as efficient in extremely cold climates where temperatures fall below -20°C. In such cases, additional heating sources may need to be installed, increasing the overall cost of the system.
  2. Initial investment. Although the operating costs of heat pumps are lower compared to traditional systems, the initial cost of purchasing and installing them can be significant. This can be a barrier for some consumers, especially those on a tight budget.

Heat pump applications

Home heating and cooling

Heat pumps are widely used in residential buildings to provide heating in the cold season and cooling in the summer. Due to their ability to transfer heat from the outside environment to the room and vice versa, they can significantly reduce energy costs. Heat pumps can be integrated with water heating systems, thus providing a full range of services for comfortable living.

Use of heat pumps for floor heating, water heating and air conditioning

Industrial and commercial use

In industry and commerce, heat pumps are used to heat and cool production and office spaces, as well as to heat process water. This not only helps to create optimal working conditions but also helps to reduce the operating costs of businesses. In addition, the use of heat pumps in commercial facilities such as shopping centers and hotels improves the environmental profile of the business and its appeal to consumers.

Innovative solutions and cases

Heat pumps are also used in innovative projects, for example in systems for utilizing waste heat from industrial plants for heating residential areas. Such solutions not only increase energy efficiency but also help to reduce harmful emissions into the atmosphere. In addition, the development and introduction of new heat pump models capable of operating at extremely low temperatures opens up additional opportunities for their use in regions with harsh climates.

Installation and maintenance of heat pumps

The installation and maintenance of heat pumps are key aspects to ensure their efficient and long-term performance. Proper equipment selection, quality installation, and regular maintenance can significantly increase system efficiency and extend the life of the system.

Basic installation steps

Installing a heat pump starts with careful planning and preparation. The first step is to analyze the terrain and determine the best location for the installation of the outdoor and indoor units. For ground source and water source heat pumps, additional soil or water body investigation will be required. Once the type of heat pump has been selected and its location has been determined, the installation of the system should begin, which includes installing the outdoor unit, laying the piping, and connecting the indoor unit to the house heating system.

Recommendations for equipment selection

The selection of a heat pump should be based on several key factors, including the climate conditions of the region, the size and insulation of the home, and individual heating and cooling needs. It is also important to consider the energy efficiency of the equipment and its compatibility with the existing heating system. It is recommended to choose equipment from trusted manufacturers with a good reputation and warranty service.

Choose your heat pump

Maintenance and operation requirements

Regular maintenance of the heat pump is an essential part of its operation. This includes checking and cleaning filters, monitoring refrigerant levels, and inspecting the outdoor and indoor units for damage or leaks. It is recommended that professional maintenance is carried out at least once a year, which will help to prevent possible malfunctions and extend the life of the system.

Indicative prices for different types of heat pumps

Heat pump prices vary depending on the type of system and its capacity. Air-to-water systems are usually the most affordable, with a starting price of around 3,500 to 4,800 EUR for an 8 kW installation, which is well suited for insulated houses. Water-to-water and earth-to-water systems, which require more complex installation, including drilling wells or laying horizontal collectors, can cost between 2,000 and 5,000 EUR, not including the cost of wiring and installation of heating systems.

Calculation of the payback period for heat pumps for heating and cooling the house

The payback period for heat pumps depends on many factors, including climate conditions, current heating and cooling costs, and energy costs. On average, heat pumps pay for themselves within 5 to 10 years due to energy savings. The efficiency of heat pumps, as measured by the coefficient of energy conversion (COP), can be as high as 5.3, which means that for every kilowatt of electricity consumed, up to 5.3 kilowatts of heat energy are generated.

Examples of successful implementation and operation

Many homeowners and businesses have already appreciated the benefits of using heat pumps. For example, in Serbia, where the cost of traditional solid fuel heating can reach 1,500-3,000 EUR per heating season, switching to heat pumps can cut costs by about half. In addition, government subsidies and support programs make investments in heat pumps even more attractive, accelerating the payback period.

Frequently Asked Questions

What is a heat pump and how does it work?

A heat pump is a device that transfers heat from the outside environment (air, water, ground) into your home for heating or, conversely, pumps heat out of your home for cooling. It works on the principle of circulation of Freon, which absorbs and releases heat by changing pressure and temperature.

Can heat pumps work in very cold weather?”

Yes, modern heat pumps can work efficiently even in extreme cold weather. Technology is constantly improving, allowing heat pumps to provide a comfortable temperature in the house all year round.

Can a heat pump be used to heat water?

Yes, there are heat pump models designed to prepare domestic hot water. This is an economical and efficient way of providing hot water to the home.

Which heating systems are suitable for heat pump operation?

Heat pumps can work effectively with both radiator heating systems and underfloor heating systems. It is important that the heating system is properly designed and installed to work optimally with the heat pump.

Can a heat pump be installed in an already-built home?

Yes, heat pumps can be installed either during the construction phase or in completed buildings. It is important to carefully analyze the heat losses of the building to determine the most suitable type of heat pump and its capacity.

How economical are heat pumps in operation?

Heat pumps are considered one of the most economical ways to heat and cool buildings. Their efficiency depends largely on the quality of installation, building insulation and climatic conditions, but in general they can significantly reduce energy costs.

Are there government subsidies for heat pump installation?

Many countries have programs to support and subsidize the installation of heat pumps as part of a strategy to improve energy efficiency and reduce carbon dioxide emissions. It is advisable to check with local authorities or heat pump suppliers for this information.

What is a heat pump COP?

The COP (Coefficient of Performance) of a heat pump is an index that describes the efficiency of converting the energy input into heat energy. It is equal to the ratio of the heating power the heat pump can provide to the power input. For example, if COP is 4, it means that the heat pump needs to consume 1 kilowatt of electrical energy to produce 4 kilowatts of heat energy. Thus, three-quarters of the energy for heating comes from the outside environment, making the heat pump an efficient means of heating. A high COP indicates a higher efficiency of the heat pump and therefore lower running costs for the user. However, it is worth remembering that the actual COP can vary depending on the operating conditions, such as outdoor temperature and room temperature.

What is the EER of a heat pump?

The EER (Energy Efficiency Ratio) of a heat pump is an index used to evaluate the efficiency of a cooling system. It is defined as the ratio of the unit’s cooling capacity (expressed in Btu/hour) to the power consumption in watts under standard operating conditions. This ratio measures how efficiently a heat pump uses electricity to cool a space. A high EER indicates that the heat pump is operating more efficiently, using less electricity to achieve the desired level of cooling. This makes it more economical to operate and a greener choice than units with a low EER. It is important to note that EER is commonly used to evaluate the efficiency of cooling systems, while another metric, COP (Coefficient of Performance), is more commonly used for heating systems. Both of these metrics are important when selecting a heat pump because they help determine how efficiently the unit will operate in both cooling and heating modes.

Энергоэффективность тепловых насосов в зависимости от SEER и SCOP
Energy efficiency of heat pumps depending on SEER and SCOP
What is the cooling capacity of a heat pump?

The cooling capacity of a device is a parameter that indicates the ability of a cooling system (e.g. heat pump, air conditioner or refrigerator) to reduce the temperature and maintain it at a given level in a room or system. This metric is usually measured in kilowatts (kW) or British thermal units per hour (Btu/hr). It indicates the amount of heat energy that a unit can effectively remove from a room in a given time. In the context of cooling efficiency, cooling capacity is used to determine how well a unit performs at cooling. Selecting a unit with adequate cooling capacity is critical to ensuring a comfortable indoor climate, especially in hot weather or in environments where a specific temperature level must be maintained for process or product storage. Cooling capacity is directly related to the energy efficiency of the unit: the higher the efficiency, the less energy is required to achieve the desired cooling effect. Metrics such as EER (Energy Efficiency Ratio for cooling) and SEER (Seasonal Energy Efficiency Ratio for cooling) help to assess how efficiently a device utilizes the electricity consumed to create the cooling effect.

What is the difference between the SEER of a heat pump and the EER?

SEER (Seasonal Energy Efficiency Ratio) and EER (Energy Efficiency Ratio) are both metrics used to evaluate the efficiency of cooling systems such as air conditioners and heat pumps in cooling mode. However, there are key differences between the two ratios related to how and when they are measured:

  • SEER measures the seasonal efficiency of the cooling system. It accounts for temperature fluctuations during the cooling season and provides the average efficiency over that period. This means that SEER better reflects the actual energy efficiency of the system under different operating conditions.
  • EER measures the efficiency of the cooling system under certain standard conditions (typically 35°C outside temperature and 27°C inside temperature with 50% relative humidity). This provides a snapshot of system efficiency under these conditions, without considering variations in temperature or operating conditions.

Calculation and application:

  • SEER is more useful for assessing overall energy efficiency and energy savings over the entire cooling season. This makes it an important indicator for regions with long cooling seasons and significant temperature fluctuations.
  • EER is useful for comparing the efficiency of different cooling systems under standard conditions. This can be useful for consumers who live in areas with high peak summer temperatures.

In general, SEER provides a broader overview of cooling system efficiency throughout the season, while EER provides a point-by-point view of efficiency under specific, tightly controlled conditions. The choice between SEER and EER depends on the specific needs and operating conditions of the cooling system.

What is the difference between SCOP and COP?.

SCOP (Seasonal Coefficient of Performance) and COP (Coefficient of Performance) are metrics used to assess the efficiency of heat pumps, but they measure this efficiency in different contexts:

COP (Coefficient of Performance):

  • COP describes the instantaneous efficiency of a heat pump. It is the ratio of the amount of heat energy produced to the amount of electricity consumed at a certain point in time.
  • For example, if COP is 4, it means that the heat pump needs to consume 1 kilowatt of electricity to produce 4 kilowatts of thermal energy. This shows the instantaneous efficiency of the device under specific conditions.

SCOP (Seasonal Coefficient of Performance):

  • SCOP represents the average efficiency of the heat pump over the heating season. It takes into account changes in climatic conditions, building characteristics and energy requirements, settings and operating conditions.
  • SCOP is calculated as the ratio of the annual heating demand (expressed in heat watt-hours) to the annual electricity consumption (expressed in electricity watt-hours). This indicator is an index of the operating costs of the heat pump.

Main Differences:

  • Momentary efficiency vs. seasonal efficiency: COP measures efficiency at a specific moment in time and under specific conditions, while SCOP gives an average efficiency rating over the entire heating season, taking into account weather fluctuations and different operating conditions.
  • Application: COP is useful for evaluating and comparing the instantaneous efficiency of different heat pumps under standard conditions, while SCOP provides a more extensive view of how a heat pump will perform under real-world conditions throughout the season, which is important for understanding overall operating costs.
What is EVI (Enhanced Vapor Injection) technology?”

EVI (Enhanced Vapor Injection) technology is an advanced vapor injection system used in heat pumps to increase their efficiency, especially in low outdoor temperatures. This technology allows heat pumps to operate efficiently even at extremely low air temperatures, thereby expanding their use in colder climates. In traditional heat pumps, efficiency decreases as the outdoor temperature drops, as it becomes more difficult for the system to extract heat from the environment. EVI technology solves this problem by introducing an additional vapor injection cycle into the compressor, which increases system pressure and temperature, improving heat transfer and increasing the overall performance of the heat pump by 12%.

EVI heat pump system efficiency comparison chart.

The use of EVI technology allows:

  • Increase the coefficient of performance (COP) of the heat pump, thereby reducing energy consumption and operating costs. Extend the operating temperature range at which the heat pump can operate efficiently, providing comfortable heating even in very cold weather.Reduce the defrosting time of the heat pump outdoor unit, which also contributes to the overall efficiency of the system.
Graphs comparing COP in HVAC systems with inverters.

EVI technology thus makes heat pumps more versatile and cost-effective for use in different climates, especially in regions with cold winters.

What is R32?

R32, also known as difluoromethane, is the refrigerant in modern heat pumps. The R32 heat pump has gained popularity as an alternative to older refrigerants such as R22 and R410A due to its lower environmental impact and high energy efficiency.

Myths and misconceptions about heat pumps

1. Heat pumps are inefficient in cold climates

This is one of the most common misconceptions. Modern heat pumps are designed in such a way that they can work efficiently even at very low air temperatures. Technology is constantly improving, allowing them to provide adequate heating for homes during the cold winter months.

2. Installing a heat pump is too expensive

While the initial cost of installing a heat pump may be higher than traditional heating systems, it pays for itself in the long run by significantly reducing energy costs. As cited in sources, heat pumps can reduce heating energy consumption by up to 75%, making them a cost-effective option.

3. Heat pumps are difficult to maintain

Heat pumps require much less maintenance than systems based on fuel combustion. It is sufficient to carry out an annual inspection, which can be carried out by yourself or by a specialist. This makes them much easier to operate than traditional heating systems.

4. Heat pumps can only heat

This is another common misconception. Heat pumps can not only heat rooms in winter but also cool them in summer, working on the principle of an air conditioner. This makes them extremely versatile and allows you to use one system to provide comfort in your home all year round.

5. Heat pumps are not environmentally friendly

On the contrary, heat pumps are one of the most environmentally friendly options for heating and cooling. They utilize renewable energy sources (air, water, ground) and reduce carbon emissions compared to fossil fuel systems. This makes them an excellent choice for those seeking a more sustainable and eco-friendly lifestyle.

Results and perspectives of heat pump technology development

Why consider heat pumps as an alternative to traditional heating and cooling systems

In conclusion, heat pump technology represents a promising and environmentally friendly solution for heating and cooling systems. With the global trends to reduce carbon emissions and improve energy efficiency, heat pumps act as an important element in the strategy to achieve these goals. Their ability to utilize renewable energy sources such as air, water, and ground makes them an ideal choice for modern heating and cooling systems.

Heat pumps not only reduce dependence on fossil fuels and associated carbon emissions but also provide significant savings in the long term due to their high energy efficiency. With energy prices constantly rising, an investment in heat pumps can pay for itself in a relatively short period, while providing comfort and user-friendliness.

In addition, the ease of installation and maintenance makes heat pumps an affordable solution for a wide range of consumers, including private homes, multi-family buildings, and commercial facilities. As technology advances and heat pumps become more efficient, their use will only increase, offering increasingly sustainable and cost-effective options for heating and cooling.

In light of these facts, heat pumps deserve attention as a reliable and environmentally friendly alternative to conventional heating and cooling systems. Their role in meeting global targets for reducing environmental impact and improving energy efficiency will only increase, making them a key element in a sustainable development strategy.

Additional resources for studying the topic

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