P32AF-2C Johnson Controls Pressure Control

Overview

The Johnson Controls P32AF-2C is a sensitive differential pressure switch designed to sense the flow of air or low positive gauge pressure in combustion and building automation applications. It uses a spring-loaded Buna-N diaphragm to actuate a dust-tight SPDT snap switch when pressure changes are detected, providing crucial proof of airflow for system operations.

Features

• Easy-to-read internal set point scale concealed by the cover.
• Versatile mounting options, including a supplied “U” bracket.
• Durable construction featuring a zinc-plated steel housing and polycarbonate cover.
• Set point switching repeatability with a close differential operating mechanism.

Specifications

• Set Point Range: 0.05 to 5.0 inches of Water Column (WC).
• Sensitivity: 0.025 inches WC at minimum set point.
• Switch Type: SPDT (Single Pole Double Throw), automatic reset.
• Electrical Rating: 10 A resistive, 24 to 277 VAC; Pilot duty 125 VA at 24 VAC, 360 VA at 120-277 VAC.
• Pressure Connections: High pressure: 1/8 in. internal NPT, 1/2 in. NPSM external; Low pressure: Molded 1/8 in. internal NPT.
• Operating Temperature: -40°F to 165°F (-40°C to 75°C).
• Maximum Overpressure: 1 PSIG (Burst pressure up to 27.7 inches WC).

Applications

• Pulse combustion appliances and power-vented exhaust systems to ensure proper system ventilation.
• Air proving with electric duct heaters, humidifiers, and other HVAC equipment to protect against overheating when airflow stops.
• Maximum pressure and airflow control for variable air volume (VAV) systems.
• Clogged filter detection and monitoring for icing on air conditioning coils to initiate defrost cycles.