Application note: Heat & pumps
Heat Pumps at the Heart of the Energy Transition
As part of global efforts to reduce CO₂ emissions and combat climate change, the HVAC industry has become a key area of focus. Across Europe, heating and cooling account for nearly half of total energy consumption, and a significant portion of this energy is still generated using fossil fuels.
For this reason, governments, manufacturers, and system designers are accelerating the adoption of heat pump technology, which is widely recognized as one of the most effective solutions for improving energy efficiency and reducing dependence on conventional fuel-based heating systems.
Over the past few years, the heat pump market has experienced rapid growth, driven by government incentives, stricter environmental regulations, and increasing demand for sustainable building technologies.
How Heat Pumps Work
A heat pump transfers thermal energy from a low-temperature source to a higher-temperature environment through a refrigeration cycle.
The operating principle relies on controlling the pressure of a refrigerant:
- The compressor increases the refrigerant pressure.
- The refrigerant absorbs heat from the external environment.
- The captured heat is transferred to the building or domestic hot water system.
- An expansion valve reduces the refrigerant pressure and temperature.
- The cycle then repeats continuously.
By incorporating a reversing valve, the process can be reversed, allowing the same system to provide both heating and cooling functions throughout the year.
Modern heat pumps are available in several configurations, including:
- Monoblock systems
- Split systems
- Hybrid systems
- Air-to-water heat pumps
- Water-to-water heat pumps
- Geothermal heat pumps
The Growing Adoption of R290 Refrigerant
One of the most significant trends in the heat pump industry is the increasing use of R290 (propane) refrigerant.
R290 offers several advantages:
- Extremely low Global Warming Potential (GWP)
- Reduced environmental impact
- Excellent thermodynamic performance
- High energy efficiency
As a result, many European manufacturers are developing new generations of heat pumps based on R290 technology.
However, propane is classified as a flammable refrigerant, requiring additional safety measures to ensure compliance with international standards such as IEC 60335-2-40 and UL 60335-2-40.
New Design Challenges
Designing modern heat pumps involves much more than managing the refrigeration cycle.
Manufacturers must simultaneously address three key challenges:
Refrigerant Safety
The use of flammable refrigerants requires reliable monitoring and leak detection systems capable of identifying hazardous conditions before they become safety risks.
Maximum Energy Efficiency
Achieving high Coefficient of Performance (COP) values requires continuous monitoring of operating conditions and optimization of compressor and refrigeration circuit performance.
Overall System Safety
Beyond the refrigerant loop, manufacturers must also monitor the hydronic circuit, heat exchangers, and pressure and temperature conditions throughout the system.
The Role of Sensors in Heat Pump Systems
To meet these demanding requirements, modern heat pumps rely on a combination of advanced sensing technologies.
Pressure Sensors
Pressure sensors continuously monitor operating conditions within both the refrigerant and hydronic circuits.
Typical applications include:
- Compressor discharge pressure monitoring
- Suction pressure monitoring
- Compressor control
- High-pressure protection
- Low-pressure protection
- Hydronic circuit monitoring
Both ceramic pressure sensors and hermetically sealed pressure sensors are commonly used depending on application requirements.
Temperature Sensors and Thermostats
Accurate temperature control is essential for maximizing efficiency and ensuring safe operation.
Key applications include:
- Defrost thermostats
- Temperature limit switches
- Heat exchanger monitoring
- Domestic hot water temperature control
- Auxiliary electric heater protection
Refrigerant Leak Detection
Leak detection has become increasingly important, particularly in systems using R290 refrigerant.
To address this need, Sensata Technologies has developed the SGD sensor, an advanced Non-Dispersive Infrared (NDIR) solution designed to detect propane leaks within heat pump systems. By providing early leak detection, the SGD sensor helps manufacturers improve safety and comply with applicable standards.
Achieving Higher COP Through Intelligent Monitoring
The integration of pressure sensors, temperature sensors, thermostats, and refrigerant leak detection technologies enables manufacturers to optimize heat pump performance and achieve outstanding efficiency levels.
The Coefficient of Performance (COP) is defined as the ratio between the thermal energy delivered by the system and the electrical energy consumed.
The latest heat pump designs can achieve heating COP values of 4 to 4.5, meaning they generate more than four times the amount of thermal energy compared to the electrical energy required to operate the system.
This exceptional efficiency makes heat pumps one of the most attractive technologies available for reducing energy consumption and carbon emissions in residential, commercial, and industrial applications.
Sensata Technologies Solutions Available Through GVZ Components
GVZ Components supports heat pump manufacturers with a comprehensive portfolio of Sensata Technologies products for HVAC applications, including:
- Pressure sensors for refrigerant and hydronic circuits
- Safety pressure switches
- Temperature sensors
- Thermostats
- R290 refrigerant leak detection sensors
- Monitoring and protection components for advanced HVAC systems
With extensive HVAC application expertise and fast product availability, GVZ Components helps designers and manufacturers develop safer, more efficient, and fully compliant heat pump systems.
