P20BB-1C Johnson Controls Pressure Control

Overview

The Johnson Controls P70GA-27C is a single-pole single-throw (SPST) low pressure control switch engineered for precision monitoring and compressor protection in commercial refrigeration and HVAC systems. It is designed to open on a drop in pressure and features automatic reset operation once the system pressure recovers above the setpoint plus the differential.

Features

• Automatic reset function restores operation once standard pressure thresholds are reached.
• All-steel case and cover provide rugged protection for internal components.
• “Sight-Set” calibrated pressure adjustment scale allows for visible setpoint configuration.
• Compatible with all non-corrosive refrigerants.

Specifications

• Switch Action: SPST Open Low (opens on pressure drop)
• Pressure Range: 20 inches Hg to 100 psi
• Adjustable Differential Range: 7 to 50 psi
• Pressure Connection: 1/4 inch FNPT internal connection
• Maximum Working Pressure: 100 psi
• Maximum Overpressure: 325 psi

Applications

• Commercial refrigeration system cycling and low pressure cut-out control
• Compressor protection against vacuum operation
• Evaporator freeze-up prevention in air conditioning cycles
• Demand control in commercial HVAC systems utilizing non-corrosive fluids