Low GWP Refrigerants: the role of sensors in HVAC safety

The A2L sensor module from TE Connectivity enables the rapid detection of low-GWP refrigerant leaks, contributing to the safety and reliability of next-generation HVAC systems.

The growing focus on environmental sustainability and the evolution of regulations are accelerating the transition towards refrigerants with a low GWP (Global Warming Potential), characterized by a lower potential for global warming.

Among the solutions adopted in the air conditioning and refrigeration sector are: A2L refrigerants, Like R-32 and R-454B, they have low flammability characteristics and require specific safety measures.

In this context, the timely detection of gas leaks becomes a fundamental element in the design of safe, efficient HVAC (Heating, Ventilation and Air Conditioning) systems that comply with applicable standards.

To meet these needs, TE Connectivity has developed a sensor module for A2L refrigerants, Designed to ensure rapid and accurate detection of leaks, while simplifying integration into air conditioning and refrigeration systems.

A2L Refrigerants: why leakage detection is important

The use of refrigerants with reduced environmental impact represents an important step for the HVAC sector. However, the introduction of A2L-classified refrigerants entails new design considerations related to safety.

These refrigerants are characterized by a low flammability, This makes it necessary to adopt appropriate monitoring and management systems for any losses that may occur.

Refrigerant detection sensors therefore play an essential role: they promptly detect the presence of gases and provide the control systems with the information necessary to activate the planned safety measures.

The reliability of the detection, the speed of response and the ability to operate in different environmental conditions therefore become determining parameters in the choice of the sensor.

The TE Connectivity A2L sensor: features and advantages

The form TE Connectivity A2L Refrigerant Sensor It uses a gas detection technology based on thermal conductivity, with compensation for temperature and humidity.

This solution allows for the monitoring of refrigerant losses of R-32 and R-454B, ensuring reliable performance even under the operating conditions typical of HVAC applications.

Among the main advantages of the sensor are:

• Quick and accurate detection: Typical response time of 15 seconds, with a stated maximum of 30 seconds.
• Long-term reliability: Declared operational life up to 15 years.
• No on-site calibration: a feature that simplifies maintenance tasks and helps reduce the total cost of ownership.
• Compact design: Small dimensions and various mounting options facilitate integration into devices.
• Flexibility of communication: RS485 Modbus RTU protocol, with PWM and UART options.
• Compliance with safety standards: ETL certification according to UL and CSA 60335-2-40, Appendix LL.

The sensor therefore represents an interesting solution for manufacturers who wish to integrate leak detection functionality into their systems without unnecessarily increasing the design complexity.

Technical characteristics of the A2L refrigerant sensor

The TE Connectivity module is designed to operate over a wide range of temperatures and humidity levels, offering performance suitable for various air conditioning and refrigeration applications.

The main technical specifications include:

• Detected refrigerants: R-454B and R-32
• Detection range: 0–100% LFL
• Detection threshold: 10% LFL
• Accuracy: ±2.5% LFL
• Response time: typical 15 seconds, maximum 30 seconds
• Start time: 5 seconds
• Operating temperature: from -40 °C to +95 °C
• Operating humidity: 0–100% UR
• Operational life: up to 15 years
• Power supply voltage: 5–17 V DC
• Maximum current: 100 mA
• Power consumption: 0.5 W
• Communication interface: RS485 Modbus RTU
• Dimensions: 52 × 35 × 14 mm
• Protection rating: IP54
• Certification: ETL, compliant with UL and CSA standards 60335-2-40, Appendix LL

LFL (Lower Flammability Limit) indicates the lower limit of flammability, that is, the minimum concentration of gas in the air at which flame propagation can occur under defined conditions.

The sensor also features a self-locking connector and supports customized wiring solutions, with an IP67 connection option, facilitating integration into different design configurations.

Applications in HVAC systems and in household appliances

Thanks to its compact size and detection capabilities, the A2L sensor from TE Connectivity can be integrated into various types of equipment.

The main applications include:

• Air conditioners, For monitoring any leaks in the air conditioning systems.
• Scaldacqua, In configurations that use refrigeration circuits with compatible refrigerants.
• Refrigerators and freezers, For refrigeration applications that use R-32 or R-454B.

The ability to integrate the sensor directly into the equipment allows manufacturers to develop leak monitoring systems that meet the safety requirements of the new generation of HVAC devices.

Security, regulatory compliance, and simplified integration

One of the most important aspects of adopting A2L refrigerants is compliance with safety standards.

The TE Connectivity sensor is ETL certificate in accordance with UL and CSA standards 60335-2-40, Appendix LL, relating to the requirements applicable to refrigerant detection systems.

This feature, together with the rapid response time and the absence of on-site calibration, helps to simplify the development of HVAC equipment equipped with integrated safety systems.

The module also offers an interface with an autobloqueable connector and supports customized wiring solutions, facilitating installation in different design configurations.

The combination of precision, reliability and simplicity of integration This makes the A2L sensor a solution for manufacturers engaged in the development of next-generation air conditioning and refrigeration systems.

A2L sensors from TE Connectivity: information and samples available Electronic Center

The adoption of low GWP refrigerants requires components capable of combining performance, reliability and safety.

TE Connectivity's A2L sensor meets these requirements with a compact solution designed for the detection of R-32 and R-454B leakages and for integration into HVAC systems.

Contact the specialists of Electronic Center To receive more technical information, evaluate the integration of the sensor into your application and request any samples for field testing and verification.