P32AC-1C Johnson Controls Pressure Control

Overview

The Johnson Controls P32AC-1C is a sensitive differential pressure switch designed to detect air flow in ducts, low positive gauge pressure, or vacuum within Building Automation Systems (BAS) and HVAC environments. It operates by sensing pressure changes across a fixed restriction using a spring-loaded diaphragm to actuate a standard differential snap switch, often used to safeguard equipment like electric duct heaters by de-energizing them when airflow stops.

Features

• Easy-to-read internal setpoint scale plate
• Versatile mounting options including an included L-shaped mounting bracket
• Small, compact, and durable construction with a dust-tight snap switch
• High setpoint switching repeatability and reliable Buna-N diaphragm

Specifications

• Pressure Range: 0.15 to 12.0 inches W.C. (0.037 to 2.99 kPa)
• Sensitivity at Minimum Setpoint: 0.07 inches W.C. (0.017 kPa)
• Setpoint Type: Field adjustable via a concealed adjusting screw
• Contact Action: SPDT switch form
• Electrical Ratings: 15 A resistive load at 24 to 277 VAC, 1/2 hp motor rating
• Operating Temperature: -40 degrees Fahrenheit to 167 degrees Fahrenheit (-40 degrees Celsius to 75 degrees Celsius)
• Maximum Overpressure: 1 psig (6.89 kPa)
• Connections: 1/8 inch female NPT high and low pressure ports

Applications

• Air flow and pressure proving with electric duct heaters or humidifiers
• Maximum air flow controller for variable air volume (VAV) systems
• Reheat duct powered systems
• Clogged filter detection
• Detecting ice accumulation on air conditioning coils to initiate defrost cycles