System Sensor DST5 Metal Sampling Tube, 4ft to 8ft Duct Width

The System Sensor DST5 is a 5-foot metal air sampling tube designed for use with compatible System Sensor InnovairFlex duct smoke detectors in commercial HVAC fire detection systems. Engineered for air ducts measuring 4 to 8 feet wide (1.2 to 2.4 meters), the DST5 features a durable steel construction with precision-drilled inlet holes that collect representative airflow samples and direct them into the connected duct smoke detector's sensing chamber. The tube incorporates an airflow direction indicator and a locking connection to support proper orientation and secure installation. Compatible with System Sensor duct smoke detector models including the D4120, D2, and compatible addressable duct detector housings, the DST5 supports smoke detection within HVAC supply and return air systems. Its design allows installers to select the appropriate sampling length for the duct dimensions, helping maintain effective airflow through the detector. The DST5 is a passive sampling accessory that requires no electrical power or wiring and is intended for commercial offices, healthcare facilities, educational buildings, warehouses, and other properties equipped with duct-mounted smoke detection systems.

System Sensor DST5 5-Foot Metal Sampling Tube for 4-8 Foot HVAC Ducts

The System Sensor DST5 Metal Air Sampling Tube is a duct smoke detector accessory designed to collect representative air samples from commercial heating, ventilation, and air conditioning (HVAC) ductwork. Manufactured by Honeywell System Sensor as part of the InnovairFlex duct smoke detection accessory family, the DST5 is specified for rectangular air ducts measuring 4 to 8 feet (1.2 to 2.4 meters) wide. Its 5-foot nominal length and factory-drilled sampling holes allow airflow from the duct to enter the connected detector housing, where a compatible smoke sensing element evaluates the sampled air for the presence of smoke. This sampling process supports early detection of smoke circulating through HVAC equipment and ventilation pathways, helping properly configured fire alarm and building control systems initiate programmed responses such as fan shutdown or supervisory signaling. The DST5 is compatible with selected System Sensor InnovairFlex conventional and addressable duct smoke detector assemblies, including the D4120 and D2 families, as well as other detector housings that specify DST Series sampling tubes. Typical applications include commercial office buildings, hospitals, schools, manufacturing facilities, warehouses, and institutional properties requiring HVAC duct smoke monitoring.

The System Sensor DST5 features a rigid metal tube with a series of predrilled air inlet openings distributed along its length, allowing air moving through the duct to enter the sampling assembly. Its 5-foot nominal length provides an appropriately sized sampling accessory for qualifying duct installations within the manufacturer's 4- to 8-foot width category. The sampling tube incorporates a directional arrow at the connector end to identify the correct orientation relative to the duct airflow. Proper positioning ensures that the sampling holes face into the moving air stream, allowing differential air pressure to direct an air sample through the detector's sensing chamber. The tube connects to the designated inlet port of a compatible duct detector housing and is secured by the detector's integrated locking mechanism. Unlike the detector itself, the DST5 contains no smoke sensing electronics, alarm contacts, electrical terminals, or independent power requirements. Its passive mechanical design relies on the airflow characteristics of the HVAC system and the sensing capabilities of the connected smoke detector. The metal construction provides rigidity for commercial duct installations and supports secure positioning during normal HVAC operation.

For commercial duct smoke detection systems, the System Sensor DST5 serves as the airflow collection component of a compatible duct-mounted smoke detector assembly. As air moves through the HVAC duct, the tube's strategically positioned inlet holes admit air into the detector housing, where the installed photoelectric or compatible intelligent smoke sensor monitors the sample for smoke particles. The sampled air is then discharged through the detector's exhaust connection, establishing the pressure differential required for proper detection. System Sensor provides multiple sampling tube sizes to accommodate different duct dimensions, including the DST1 for ducts up to 1 foot, DST1.5 for ducts 1 to 2 feet, DST3 for ducts 2 to 4 feet, DST5 for ducts 4 to 8 feet, and DST10 for ducts 8 to 12 feet. Selecting the correct tube is essential because insufficient sampling coverage, improper inlet orientation, or inadequate duct airflow can affect detector performance. The DST5 is referenced in manufacturer documentation for System Sensor D4120, D2, DNR/DNRA, and compatible Silent Knight SK-DUCT applications, subject to the specific housing and detector installation instructions. The completed duct smoke detection system can interface with compatible fire alarm control panels, building automation systems, and HVAC shutdown equipment through the appropriate detector electronics and control wiring.

Installation of the System Sensor DST5 5-foot sampling tube involves selecting the correct mounting location, confirming the duct's airflow direction, and inserting the tube into the compatible duct smoke detector's designated sampling inlet. The manufacturer's installation instructions specify that the air inlet holes must face directly into the airflow, with the directional arrow on the tube connector used to verify correct orientation. Depending on the detector model and duct dimensions, the sampling tube must extend the manufacturer-specified minimum distance across the duct, generally at least two-thirds of the duct width for supported InnovairFlex configurations. If the tube extends beyond the opposite side of the duct, the manufacturer provides instructions for trimming, sealing, capping, and supporting the protruding section. Sampling tubes longer than 3 feet may require additional support to prevent vibration or movement within the air stream. The sampling tube end cap is essential for proper airflow operation and must be installed according to the detector manufacturer's instructions. After installation, technicians verify airflow through the sampling chamber and perform the required detector functional tests to confirm correct system operation. The DST5 does not include the duct smoke detector housing, smoke sensor, control electronics, or electrical interface equipment, which are specified separately. Combining durable metal construction, factory-drilled inlet holes, compatibility with multiple duct smoke detector families, and 4- to 8-foot duct sizing, the System Sensor DST5 provides a necessary airflow sampling component for properly installed commercial HVAC smoke detection systems.