Use the Imperial iManifold high resolution Wireless Manometer to measure total external static pressure (TESP), return static, supply static, zone pressures and draft. Make velocity pressure readings in duct systems with a user supplied Pitot tube. Mass flow technology automatically compensates for changes in air density and displays results equivalent to sea level.
This unit comes with flush mount static pressure probes which have been used for years and still sold by Dwyer Instruments. The iManifold developers wanted something simple and where the access hole could be plugged by a simple screw. The best way to test this and to make you a believer is to put one side by side in the duct with the static pressure tip (bent probe) both attached to either port on a differential manometer. If the pressure difference is zero, the tips are reading the same. The velocity in residential and most commercial systems is not high enough to effect the pressure reading of a flush port (due to Bernoulli pressures). This unit uses a very high end sensor which has excellent low range resolution. This type of sensor does extremely well with a Pitot tube to measure air velocity, and it has high enough resolution for zonal depressurization (building performance Pascal range). The developers will be adding some additional airflow calculations for variable speed systems hence the requirement for a much more accurate sensor that does not drift off zero.