Product Description

The Honeywell GD250W4NB is a compact and highly sensitive indoor air quality (IAQ) sensor designed to detect low concentrations of carbon monoxide (CO) gas. Utilizing a solid-state electrochemical sensor, it offers a detection range of 0–250 ppm with high selectivity to CO and minimal interference from alcohol vapors. The sensor provides a linear output of 2–10 VDC (default) or 4–20 mA, selectable via jumper, and is powered by a 24 VAC/DC supply. Its compact dimensions (70 mm × 122 mm × 32 mm) and IP30-rated enclosure make it suitable for installation in confined spaces such as parking garages, tunnels, and underground facilities. With a recommended coverage area of 465 m², the GD250W4NB ensures effective monitoring and ventilation control in environments where CO accumulation poses a safety risk.​

Technical Specifications

• Model: GD250W4NB
• Gas Detected: Carbon Monoxide (CO)
• Sensor Type: Electrochemical
• Detection Range: 0–250 ppm
• Accuracy:
• ±5% Full Scale (FS) for 0–100 ppm
• ±10% FS for 100–250 ppm
• Output Signal: 2–10 VDC (default) or 4–20 mA (selectable by jumper)
• Power Supply: 24 VAC 50/60 Hz or 24 VDC ±20%
• Sensor Life Expectancy: Approximately 3 years
• Coverage Area: Up to 465 m² (recommended)
• Response Time: Within 5 minutes
• Warm-up Time: Minimum 2 hours
• Protection Class: IP30
• Wiring: 3 or 4-wire compatible
• Operating Temperature: 0–50°C
• Operating Humidity: 10–95% RH (non-condensing)
• Storage Temperature: -20–60°C
• Storage Humidity: 10–95% RH (non-condensing)
• Dimensions: 70 mm × 122 mm × 32 mm