System Sensor DST1 InnovairFlex Sampling Tube
Overview
The System Sensor DST1 is a flexible sampling tube accessory engineered for InnovairFlex duct smoke detection systems. It extends the detection capability of duct-mounted detectors up to 1 foot into active HVAC ductwork—solving the problem of sampling air quality in challenging duct geometries (square, rectangular, or round) where fixed-mount detectors cannot reach. The tube installs tool-free from the front or back of the detector housing and is rated for airflow speeds of 100 to 4,000 feet per minute, making it suitable for both low-velocity return plenums and high-velocity supply runs. At 29VDC operation, it integrates directly into 4-wire photoelectric detection circuits without separate conditioning.
Compatibility
The DST1 pairs with the System Sensor D4120 InnovairFlex duct smoke detector and supports downstream monitoring in supply or return duct configurations within interconnected fire alarm networks. It is compatible with System Sensor's 4-wire photoelectric sensor architecture and works within installations using standard fire alarm panel wiring (125/250 VAC monitored control circuits). The detector can interconnect with up to 50 InnovairFlex units on the same circuit, so the DST1 scaling works across multi-zone commercial and institutional HVAC systems.
Installation Notes
The tube mounts using a patented quick-connect design—no tools, no threaded fittings required. The D4120 housing provides a ¾-inch conduit knockout for field wiring entries, and the sampling tube plugs directly into the sensor head from either mounting face. Operating temperature range is –4°F to 158°F with humidity tolerance of 0–95% non-condensing, typical for HVAC environments. Ensure adequate clearance at duct entry points and verify airflow does not exceed 4,000 fpm to prevent sensor saturation. The low-flow design (integrated into the detector) minimizes false alarms caused by dust or rapid pressure transients common in ductwork.
What's in the Box
- 1x System Sensor DST1 sampling tube assembly
