R-454B
R32/R1234yfR 454B (Opteon XL41) is a low GWP blended HFO/HFC refrigerant engineered to replace R 410A in new residential and commercial HVAC systems. With a GWP of ~466—about 78% lower than R 410A—it has become a leading AIM Act–compliant alternative, marketed by Carrier as Puron Advance and adopted by Daikin, Trane, Lennox and other major OEMs. The blend contains primarily HFO-1234yf with R-32, classified as A2L - low toxicity, mildly flammable. Not a retrofit refrigerant, R 454B serves as the foundation for next generation A2L rated equipment, and the transition represents a fundamental shift in the HVAC industry, requiring new equipment designs, updated installation practices, and appropriate safety measures for mildly flammable refrigerants.
Need R-454B Detection?
Get expert guidance on the right detection solution for your application.
Key Information
Essential safety and exposure information for R-454B
Health Effects
- Although R-454B is not toxic inhalations of high concentrations can cause headache, dizziness, shortness of breath, asphyxiation due to oxygen displacement
- Contact with rapidly evaporating liquid R-454B can cause frostbite like injuries to skin or eyes.
- As an A2L refrigerant, R-454B is mildly flammable and can ignite under the right conditions, especially near open flames, sparks, or hot surfaces.
Common Sources
- High efficiency AC units
- Light commercial HVAC
- Heat pumps
- Small commercial split systems
- High‑efficiency water‑heating applications
Exposure Limits
- WEEL
- 1,000 ppm (8-hr TWA)
- A2L flammable
- A2L flammable
- No OSHA/NIOSH/ACGIH limits
- No OSHA/NIOSH/ACGIH limits
Regulatory Status
- R‑454B is classified by ASHRAE Standard 34 as an A2L refrigerant (low toxicity, mildly flammable), and its use is governed by ASHRAE Standard 15, which sets requirements for ventilation, refrigerant concentration limits, and A2L leak detection in occupied spaces. The EPA recognizes R‑454B under its SNAP program (40 CFR Part 82) as an approved lower‑GWP alternative refrigerant subject to A2L safety controls. Related ASHRAE standards such as 62.1 (ventilation) and 90.1 (HVAC design) provide additional guidance, while NFPA 70 and NFPA 72 outline electrical safety and integration of A2L refrigerant detectors into alarm and control systems.
Detection Requirements
- Sensor Technology
- Infrared (NDIR)
- Sensor Detection Range
- 0-2,000 ppm (OEL monitoring), 0-10,000 ppm or 0-100% LEL (safety/LFL monitoring)
- Alarm Setpoints
- Low 250 ppm, Mid 500 ppm, 1,000 ppm / Low 1,000 ppm, Mid 1,500 ppm, High 2,000 ppm / Low 10% LEL, Mid 15% LEL, High 25% LEL
- Mounting
- Near floor level (heavier than air)
Related Applications
Industries and environments where R-454B detection is critical
Hotels
Continuous monitoring of refrigerant gases in hotel rooms are used to keep the indoor environment comfortable.
Chiller Rooms
Ammonia, R-410A, and A2L refrigerant detection for central plant mechanical rooms and HVAC equipment areas
Cold Storage
Refrigerant or ammonia leak and oxygen depletion monitoring for walk-in freezers, cold rooms, and temperature-controlled warehouses
Ice Arenas
Multiple gas hazards throughout ice arenas require several detectors to protect workers, spectators, and athletes.
Data Centers
Refrigerant leaks from cooling infrastructure can create asphyxiation risks, while hydrogen off‑gassing from battery systems can form an explosive hazard.
Schools
Continuous monitoring of carbon monoxide, carbon dioxide, natural gas, and nitrogen dioxide protects students and staff across school facilities - from boiler rooms and science labs to bus loading areas and cafeteria kitchens.
Detection Solutions
Sensors and detectors for R-454B monitoring
cGas Detector VRF IR Refrigerant Transmitter
An aesthetic, non-dispersive infrared refrigerant gas detector for acute leak detection in modern energy-efficient buildings utilizing Variable Refrigerant Flow (VRF) HVAC systems.
RSL Remote Stack Light
Tower light with modular LED colors with steady or flashing light settings and two different sound types. A compact, pole mounted signal light with flashing or steady modes that are clearly visible from a distance.
RDM Remote Display
Provides convenient viewing of gas level readings from a secondary location. Displays gas level readings, channel status and faults received from the FCS, offers configurable display settings.
RSW Remote Switch
Enables manual operation of equipment with emergency shutdown, activation or reset as needed. Easy push button action, satisfies compliance as required with some standards.
cGas-SC Self-Contained Controller
A self contained controller with up to 3 gas channels, Plug & Play Smart Sensor Technology and configurable logic control and priority settings. Offers superior user customization and reliable gas detection performance for monitoring many gases.
Top Mounted Strobe (Option -L)
A high powered, red LED flashing beacon that is factory installed at time of order and offers excellent flash intensity, durable vibration resistant construction and a long life. 4 flash patterns, weather and corrosion resistant.
cGas Detector IR Refrigerant Transmitter
Non-dispersive infrared refrigerant gas detector with accurate, low level leak detection, available with analog output or BACnet® or Modbus® output and Plug & Play Smart Sensor Technology.
FCS Multi Channel System Controllers
High performance controller with logic and priority settings for monitoring toxic, combustible and refrigerant gases with versatile control functionality. Available with Modbus® or BACnet® communication with BAS, supports 4-20 mA and Modbus® driven VFDs.
RSH-24V Remote Strobe & Horn
Two alarm features in one safety device, mounting fixture not included. Available in 3 different lens colours, combines a visual and an audible alarm feature into one compact, low profile device.
Related Gases
Other A2L Refrigerants we detect