Johnson Controls Low Pressure Connector P70AB-12C

The Johnson Controls P70AB-12C is a low pressure control from the P70 commercial series.

Low pressure controls serve two distinct purposes in refrigeration, and knowing which role a particular control performs is essential before adjusting it.

As a safety, it protects the compressor from running with insufficient refrigerant. A system that has lost charge runs at very low suction pressure, and several problems follow: hermetic and semi-hermetic compressors are cooled by returning suction gas, so a starved system runs the motor hot; and if the low side falls into a vacuum, any leak admits air and moisture rather than releasing refrigerant, which contaminates the system.

As an operating control, it performs pump-down. The temperature control closes a liquid line solenoid, the compressor continues running until it has drawn the low side down, and the low pressure control then stops it. Refrigerant is stored in the receiver during the off cycle, which prevents migration to the compressor crankcase.

The distinction matters because a pump-down control cycles routinely by design, whereas a safety control that operates is reporting a fault.

Applications include commercial refrigeration, walk-in coolers and freezers, and refrigeration racks.

Brand

Johnson Controls

SKU

P70AB-12C

Category

Pressure Switches

Weight

1.8 lbs

Dimensions

5.20" x 4.00" x 2.40"

Price

$164.00

Availability

In stock

Rating

0 / 5.0