05 June 2026
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Advertorial
The industry-wide migration toward A2L refrigerants - driven by evolving environmental regulations – has made a wide variety of impacts across the global HVAC industry.
Verticals outside of traditional building cooling – such as commercial and transport refrigeration and data center cooling - are about to shift to A2L frameworks. And those shifts toward A2L have also introduced new thermal and safety considerations into HVAC/R system design.
DATA CENTER EXPANSION DRIVING COOLING GROWTH
With the rapid expansion of AI and other computing-intensive systems, demand for data center infrastructure has scaled exponentially in recent years. Those growth initiatives are also balanced by a continued emphasis on energy efficiency and reducing consumption - particularly in thermal management systems, which represent a significant portion of total power draw. These new systems are leveraging A2L refrigerants to meet global climate change regulations.
Integrating A2L refrigerants into data center cooling infrastructure- particularly in CRAC (Computer Room Air Conditioning) and CRAH (Computer Room Air Handling) systems - necessitates a comprehensive redesign of safety-critical components. Chief among these is the implementation of advanced leak detection systems capable of operating reliably in high-humidity, thermally dynamic environments.
SMALLER COMMERCIAL REFRIGERATION SYSTEMS LEVERAGING A2L
Commercial refrigeration systems often rely on high-capacity compressors to accommodate the extreme pressures required by CO2-based refrigerant loops, which can reach up to 150 bar (≈2100 psi). While CO2 offers low global warming potential (GWP), its high operating pressure necessitates robust mechanical design and specialized components, making it less viable for compact systems such as those used in convenience stores.
Ammonia (NH3) remains another alternative due to its excellent thermodynamic efficiency and zero GWP. However, its toxicity and stringent safety requirements limit its applicability in consumer-facing or mobile refrigeration platforms.
To comply with safety standards such as UL60335-2-40, A2L-based systems require integrated leak detection mechanisms. Sensor placement and performance are critical, particularly near the evaporator coil, which is an area prone to refrigerant leakage due to thermal cycling, condensation, and mechanical stress.
Moreover, the mobile nature of commercial refrigeration units - often relocated across retail environments - introduces variability in ambient conditions and airflow patterns, further complicating sensor calibration and reliability. Engineers
must account for these dynamic factors when designing leak detection systems, ensuring robust performance across a range of operating environments while maintaining compliance and minimizing false positives.
TRANSPORT REFRIGERATION SHOWS EXPANSION OF A2L ECOSYSTEM
Refrigerated transport solutions are a vital component of the logistics world, reducing food waste and keeping other goods such as refrigerated medical supplies safe
during shipment. These transport solutions rely on special temperature-controlled vehicles such as trucks, ships, and containers, equipped with built-in refrigeration systems that maintain cooling throughout the entire journey.
Transport refrigeration systems require precise temperature control and constant monitoring to operate their complex thermal cycles with cargo integrity and regulatory compliance. As the industry adopts low global warming potential (GWP) refrigerants for environmentally responsible operations, performance expectations on electronics within the system continue to rise.
Unlike household refrigerators, transport refrigeration
systems must be built to withstand vibration, environmental extremes, and power fluctuations. The demanding environment poses a risk of impacting critical monitoring and control systems. Failures may result in product spoilage, financial loss, and safety risks.
To meet environmental demands and rising performance expectations, transport refrigeration systems need electronic components they can rely on, with accurate monitoring and control under rugged operating conditions.
Gas detection sensors compatible with A2L refrigerants are an ideal solution for the recent adoption of low global warming potential refrigerants. By constantly monitoring the acoustic resonance of the surrounding air, the Sensata ResonixTM RGD leak detection sensor can detect even low-level leaks of mildly flammable A2L gases, supporting safety and environmental objectives. The sensor has also been tested in a wide array of conditions, including high vibration situations, and acidic salt fog environments to ensure corrosion resistance.
THERMAL DRIFT AND SYSTEM-LEVEL IMPACTS IN A2L-BASED HVAC ARCHITECTURES
The transition to A2L refrigerants has necessitated a reevaluation of pressure and temperature thresholds across HVAC system designs. These mildly flammable refrigerants typically operate at elevated discharge temperatures, which can exacerbate thermal drift, particularly in high-side pressure sensing and control components.
High-pressure cutoff switches, which are essential for maintaining operational safety and compliance with regulatory standards (e.g., UL, IEC), are especially susceptible. Excessive thermal drift can lead to premature or delayed actuation, undermining system reliability and increasing the risk of false trips or failure to engage under fault conditions.
This challenge is compounded by the growing emphasis on energy efficiency as a market differentiator. Erroneous pressure readings due to thermal instability can disrupt control logic, preventing optimal modulation of compressors, fans, and pumps. The result is suboptimal system performance, elevated energy consumption, and increased operational costs due to unnecessary cycling or maintenance interventions.
Precision in thermal management is particularly critical in applications requiring tight environmental control (e.g., data centers, pharmaceutical storage, or process cooling). In these contexts, low-drift pressure sensors and integrated smart control systems are essential. Enhanced thermal stability ensures accurate real-time data acquisition, enabling more responsive and intelligent system behavior through advanced control algorithms.
LOOKING AHEAD IN A2L SYSTEM DEVELOPMENTS
As A2L and A3 refrigerant-based HVAC systems continue to proliferate across global markets and diversify into new verticals, it is increasingly evident that this transition marks the beginning of a sustained period of iterative design refinement rather than a singular market shift. The evolving regulatory landscape and refrigerant characteristics are driving continuous innovation in system architecture, component integration, and control strategies.
HVAC systems remain a focal point in global energy reduction initiatives, given their substantial contribution to commercial building energy consumption - typically ranging from 40% to 60% of total usage. This positions HVAC platforms as a primary target for efficiency gains and carbon footprint reduction.
The adoption of new refrigerants introduces shifts in thermal operating conditions, necessitating a reevaluation of system components such as compressors, expansion valves, sensors, and control logic. Engineers must assess the downstream effects of altered temperature profiles to ensure that system performance remains within optimal parameters. This includes maintaining thermal stability, minimizing drift in sensing elements, and ensuring compatibility with smart control systems designed to maximize energy efficiency.
The next phase of HVAC innovation will be characterized by adaptive design methodologies, where component selection and system calibration are continuously refined to meet the dual demands of regulatory compliance and high-efficiency operation.
Sensata Technologies has discussed the transition to A2L/A3 refrigerants in a webinar focused on next‑generation sensor technologies enabling safer, more reliable, and regulation‑ready HVAC/R leak detection. Watch the on-demand webinar HERE.
