The Air Monitor STACK-probe is an airflow traverse probe based on differential pressure (Pitot-Fechheimer) technology for measuring airflow; the same technology that will be used during the certification process to verify relative accuracy of the flow monitoring system. Each STACK-probe consists of two separate round tube self-averaging manifolds; one to measure the stack total pressure, and the other to measure stack static pressure. Multiple Pitot-Fechheimer ports are positioned on each manifold on an equal area basis (for rectangular stacks) or on an equal concentric area (for circular stacks). Similarly, average stack temperature is measured using a temperature probe with multiple sensing elements spaced along the probe length.
As a basic instrument, the STACK-probe does not require any initial or periodic calibration to measure flow accurately. As a passive device with no moving parts or active electrical circuits, removal of the STACK-probe from the stack after installation for repair or calibration is not required.