Extech 407910 Heavy Duty Differential Pressure Manometer (29psi)

The 407910 heavy-duty differential pressure manometer is built for demanding field environments where wide-range pressure measurement is needed. It features dual input ports (P1 and P2) which allow the user to measure either gauge mode (one port to atmosphere) or true differential mode (P1 minus P2) so positive and negative values are displayed. The measurement span extends to ±29 psi (≈±2 bar) or equivalently up to ±802 inches of water or ±2000 mbar in other units, giving wide coverage from airflow/ductwork systems to heavier-industrial pressure differences. The meter allows selection of eight different units of measure including psi, mbar, kg/cm², mmHg, inHg, mH₂O, inH₂O and atmospheres, which adds flexibility for different regional practices or technical requirements. On the front panel you’ll find controls for ZERO/offset (to null baseline conditions), UNIT selection, HOLD (freeze display), RECORD/RECALL (for Min/Max values), and an auto-power-off to conserve battery life. The meter includes quick-disconnect (4 mm) fittings for rapid hose changes, comes with a protective rubber holster including fold-out stand for bench work, and has an RS-232 serial interface for PC connection and data logging. Accuracy is around ±1% of full scale on most units (±2% for mbar) and resolution is as fine as 0.02 psi in the psi mode. A typical kit includes two quick-disconnect fittings, a 9-V battery, carrying case and instructions. This instrument makes it suitable for HVAC technicians, industrial maintenance teams and other professionals who need robust, accurate differential pressure measurement over a significant range with logging capability.

Features

• Wide-range measurement: ±29 psi (approx ±2.0 bar) and up to ±802 inches of water (≈±20 mH₂O) providing broad application coverage.

• Dual inputs (P1 & P2) allowing true differential or gauge pressure measurement modes for flexible use.

• Eight selectable units of measure including psi, mbar, kg/cm², mmHg, inHg, mH₂O, inH₂O and atm — ideal for varying regional and industry-standard preferences.

• High resolution and accuracy: for example in psi mode resolution is 0.02 psi and accuracy is ±1% of full scale on most units.

• Built-in functions such as ZERO/offset correction (to null baseline), Data Hold, Min/Max recall and an auto power-off feature for battery conservation.

• Rugged design: protective rubber holster with fold-out stand, quick-disconnect fittings, portable size (~180 × 72 × 32 mm) and lightweight (~345 g) for field work.

• RS-232 PC interface for connection to data-acquisition software and logging of readings.

Includes

• Pressure Manometer
• 2 Quick-disconnect fittings
• 9V Battery
• Protective holster with stand
• Manual
• Case
• 3 Year Warranty