Freon Gas Sensor (Freon Gas Detector) — Fixed Monitoring for HVAC/R
Winsen® manufactures fixed Freon gas sensors for legacy “Freon” refrigerants (e.g., R12, R22*) and modern A1/A2L/A3 gases (R134a, R410A, R32, R454B, R1234yf/ze, R290, R600a). Choose NDIR for ppm early warning or MOS/NDIR for %LEL safety interlocks. Standard 4–20 mA, RS-485 Modbus, and relay outputs streamline BMS/PLC integration.
- A1 / A2L / A3 Coverage
- NDIR ppm & MOS %LEL
- OEM/ODM • Bulk Orders
- Fast Lead Time
Model Guide — Select by Gas Family & Measurement
A1 HFC/HFO — NDIR PPM
- Ranges: 0–1,000 / 0–5,000 ppm (customizable)
- Outputs: 4–20 mA, RS-485 Modbus, 1–2 relays
- T90 ≤ 30 s • Low drift, long life
*R22/R12 are legacy service gases in many regions.
A2L Low-GWP — NDIR PPM / %LEL
- PPM early warning and/or 0–100% LFL/LEL
- 4–20 mA / RS-485 / relays
- Ideal for VRF/VRV rooms & heat pumps
A3 Flammable — %LEL Safety
- Range: 0–100% LEL (NDIR-LEL or MOS)
- Relays for ventilation & shutdown interlocks
- IP65 housings available
What “Freon” Means
In day-to-day language, people often say “Freon” to mean any refrigerant. Technically, Freon™ is a trademark historically used for certain CFC/HCFC/HFC products (e.g., R12/R22). On this page, “Freon gas sensor” refers broadly to electronic fixed sensors that detect refrigerant gas in HVAC/R spaces.
NDIR Refrigerant Sensor
Semiconductor Refrigerant Sensor
Technology Options
| Technology | Best For | Range | Advantages | Considerations |
|---|---|---|---|---|
| NDIR (Infrared) | A1 ppm; A2L ppm/%LEL | ppm → %LEL | High selectivity, low drift, not O₂-dependent | Protect optics from condensation/dust (filters/enclosures) |
| MOS (Semiconductor) | A2L/A3 %LEL | 0–100% LEL | Fast response; robust; cost-effective | Possible cross-sensitivities; periodic calibration recommended |
| Catalytic Bead | General hydrocarbons (A3) | 0–100% LEL | Mature technology | Needs O₂; can be poisoned by silicones/lead |
Typical Applications
VRF/VRV indoor units & hotel rooms
Mount low (~150–300 mm above floor) near indoor units and pooling points. Pre-alarm → fresh-air purge; main alarm → fan/indoor-unit shutdown.
Chiller & machinery rooms, compressor racks
Place near compressors, oil separators, valves, and floor low spots/sumps; use IP-rated housings and BMS interlocks.
Cold storage & refrigerated display cases
Install beneath cases and along manifolds/pipe runs; choose condensation-resistant designs and curtain/exhaust interlocks.
Data center in-row/CRAC units
Position in return air, under raised floors, and near coils; ppm early warning protects uptime.
Heat pumps & general HVAC equipment
For A2L/A3, use %LFL tiers (~25% pre-alarm; ~50% main) to trigger ventilation and safe shutdown.
Core Specifications
| Parameter | Value / Option |
|---|---|
| Measurement | NDIR ppm and/or %LFL (MOS/NDIR-LEL) |
| Outputs | 4–20 mA (2/3-wire), RS-485 Modbus RTU, 1–2 relays (N.O./N.C.) |
| Response Time (T90) | ≤ 20–30 s typical |
| Supply | 12–24 VDC (others on request) |
| Operating Conditions | −20…+50 °C; 15–95% RH non-condensing (model-dependent) |
| Enclosures | Wall, panel, duct; housings up to IP65 |
| Compliance | CE & RoHS; designed for BMS/PLC integration |
Placement & Setpoints — Good Practice
- Mounting height: Most refrigerants are heavier than air ⇒ mount low; confirm with on-site airflow.
- Coverage: ~5–10 m radius per sensor in open rooms; add units near valves/joints and low pockets.
- Alarms: A2L/A3: pre-alarm ≈25% LFL; main ≈50% LFL. A1: ppm bands (e.g., 1,000–5,000 ppm) per project spec.
- Interlocks: Pre-alarm → ventilation; Main → equipment shutdown + beacon/horn/BMS event.
Finalize thresholds and quantities against your project specification and local codes.
Why Global Clients Choose Us?
The company consistently adheres to the quality policy of “Fine Craftsmanship, Scientific Innovation, Pursuit of Excellence, and Value-Added Service.” By formulating production process control plans and work instructions, it has established a standardized, accountable, and regulated process management system. Additionally, the company has independently developed an MES production management system, enabling comprehensive and visual management across the entire workflow.
30+ YEARS OF EXPERIENCE
R&D, manufacture and sales of sensors and sensing solutions.
QUALITY GUARANTEE CONTINOUS IMPROVEMENT
Complete and rigid process flow control, coupled with significant improvements.
INTERNATIONAL MARKET
Deliver sensing products to more than 100 countries and regions.
STABLE SUPPLY CHAIN RELIABLE PRODUCTION
Core components not subject to constraints, advanced equipments for manufaturing and test.
R&D STRENGTH TECHNOLOGY INNOVATION
200+ patents, 180+ R&D team members, self-built labs for continous innovation.
SERVIÇO COMPLETO
Professional consultation, fast delivery, 24 hours after-sales support.
Leading the Industry, Innovative & Controllable Technology
With robust R&D capabilities, we maintain sustained input in R&D and unwavering commitment to technological innovation. This not only ensures that we remain at the forefront of industry but also drives continuous innovation, leading the future trend of the sensing industry.
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FAQs — Freon Gas Sensors
Is a Freon gas sensor the same as a refrigerant gas sensor?
In common usage, yes. “Freon” is often used generically for refrigerants. Our fixed electronic sensors detect the specified gas family regardless of branding.
Do I need ppm or %LEL?
Use ppm (NDIR) for early-warning/comfort monitoring. Use %LEL (MOS or IR-LEL) to drive safety interlocks for A2L/A3 gases. Many facilities deploy both tiers.
How many sensors per room?
As a guideline, ~5–10 m radius coverage per sensor in open rooms. Add devices near valves, joints, and low pockets where gas can accumulate.
Calibration interval?
Typical: every 12–24 months with periodic bump tests. Dusty/humid or solvent-rich areas may need more frequent checks and filter maintenance.
Integration with BMS/PLC?
4–20 mA analog scaling (e.g., 4 mA = 0; 20 mA = full-scale), RS-485 Modbus RTU (address/baud configurable), and 1–2 relays for pre-alarm/main interlocks.
Can Winsen customize for OEM programs?
Yes—ranges, firmware/Modbus mapping, connectors/harnesses, housings (IP rating), labels/branding, and packaging are customizable for volume deployments.
