Dwyer Instruments A-421 Static Pressure Tip with Built-In Surge Damper 6" Probe

The Dwyer Instruments A-421 Static Pressure Tip is a precision measurement accessory designed to accurately measure duct static air pressure in HVAC systems. This complete assembly provides reliable pressure readings for monitoring air filters, cooling coils, blower inputs, and discharge pressures.

Complete Assembly Includes:

• 6-inch (152 mm) insertion depth probe with four radially drilled 0.040" sensing holes
• Silicon rubber hose for connection
• Mounting screws and hardware
• Built-in surge damper for stable, consistent readings

Key Features:

• Built-in surge damper ensures stable readings by minimizing pressure fluctuations
• Mounts in standard 3/8" duct hole for easy installation
• Compatible with manometers, Magnehelic® gauges, pressure switches, and controllers
• Optional pressure spike reducer available for additional dampening
• RoHS compliant construction

The A-421 is ideal for use with pressure measurement instruments to monitor static pressure drop across HVAC components, enabling proper system balancing and performance verification. The integrated surge damper provides superior reading stability compared to standard pressure tips, making it perfect for applications where steady, accurate measurements are critical.