Dwyer A3001 Photohelic Pressure Switch 25 Psi

Product Description

The DWYER A3001 is a Photohelic pressure switch designed for precise differential pressure measurement and switching in HVAC, industrial, and process control applications. It provides 2% accuracy and a maximum pressure rating of 25 psi, making it suitable for demanding monitoring tasks. The unit features a 1/8 inch NPT threaded connection and is rated for environments up to 120 degrees F. The Photohelic design combines an analog pressure gauge with an adjustable set-point switching function, allowing technicians to monitor pressure and trigger alarms or control circuits from a single instrument. HVAC technicians, industrial service techs, and instrumentation professionals typically install and service this switch.

The A3001 is well suited for residential and light commercial HVAC systems, clean room monitoring, duct pressure control, and filter status indication. Its 1/8 inch NPT port allows direct connection to standard pressure taps on ductwork, piping, or equipment panels. The 1 inch water column range increment suits low-differential pressure sensing tasks common in air-handling and ventilation system diagnostics.

Key Features

• 25 psi maximum pressure rating for reliable operation in moderate-pressure systems
• 2% accuracy for dependable pressure monitoring and switching
• 1/8 inch NPT threaded port for standard pressure tap connections
• Integrated gauge and adjustable switching function in one instrument
• Rated up to 120 degrees F for typical HVAC and light industrial environments
• 1 inch water column range suits low-differential HVAC pressure sensing

Compatibility

Designed as an OEM-style replacement or direct installation instrument for HVAC, ventilation, and process control systems requiring differential pressure monitoring with integrated switching capability via a 1/8 inch NPT connection.

Installation Notes

Installation should be performed by a licensed HVAC technician or qualified instrumentation professional. Power down the system and relieve all pressure from the sensing lines before connecting or disconnecting the unit. Use appropriate thread sealant on the NPT fitting and avoid over-tightening to prevent port damage. Wiring to control circuits should comply with applicable NEC requirements for the installation environment.