Stack Flow Sensors

Stack flow sensors are mounted directly on the stack or duct wall using a standard ANSI 4-inch pipe flange. OSI sensors require a minimum of 2 upstream and 1 downstream pipe diameters of straight duct for accurate cross-stack measurement. The transmitter and receiver are positioned on opposite sides of the stack to measure flow across the full measurement path.

The stack flue sensor on a Pentair pool heater is typically located in the exhaust flue or stack outlet near the top of the heater unit. It monitors flue gas temperature to detect unsafe overheat conditions or blocked flue situations. Note that OSI's industrial stack flow sensors are distinct products engineered for large industrial emissions monitoring rather than residential or commercial pool heating equipment.

OSI's OFS stack flow sensors feature built-in automatic calibration check and continuous self-test diagnostics, eliminating the need for manual field testing. The system continuously monitors its own performance and signals any anomaly. For industrial compliance verification, the sensors support EPA 40 CFR Part 75 test protocols. OSI also provides remote diagnostics and on-site field engineering support for performance verification.

No. OSI's optical stack flow sensors are factory pre-calibrated and feature drift-free measurement technology. The NIST-certified algorithm requires no field calibration ever. Built-in automatic calibration checks and continuous self-test diagnostics ensure ongoing accuracy without technician intervention, significantly reducing maintenance costs and compliance overhead for facilities operating under EPA 40 CFR Part 75.

Yes. The OFS-2000W model is specifically designed for high-opacity environments including wet scrubbers and bag houses. It features Automatic Gain Control (AGC) to compensate for opacity variations caused by particulate matter and moisture. Measurement accuracy is unaffected by changes in gas density, temperature, pressure, or the presence of entrained liquid droplets, ensuring reliable performance in the most challenging stack conditions.

OSI's OFS-2000 stack flow sensor supports RS-232 and MODBUS RTU as standard communications interfaces, with optional RS-485, Ethernet, and cellular modem connectivity. Data updates are delivered once per minute, with instantaneous intensity readings available every 10 seconds. These options enable seamless integration with plant-level SCADA, DCS, and emissions monitoring data management systems.