Johnson Controls P70GA-11 Pressure Control

The Johnson Controls P70GA-11 Pressure Control is a heavy-duty industrial switch designed for precision low pressure cut-out and pump-down control in commercial refrigeration and HVACR systems. Built with a rugged all-steel case and cover, this adjustable pressure switch operates within a range of 20" Hg to 100 psi, making it compatible with a wide variety of non-corrosive refrigerants including R-22, R-134a, R-404A, and R-507. This specific model features a 4-wire 2-circuit contact block, providing one normally open (NO) and one normally closed (NC) set of contacts for versatile wiring of auxiliary alarms or secondary control circuits.

Engineered for technical reliability, the P70GA-11 utilizes an open low action, where the main contacts open when the system pressure drops below the setpoint. It includes sight-set calibrated pressure adjustment, allowing technicians to verify settings through a visible scale without removing the NEMA 1 enclosure cover. The 1/4" FNPT connection ensures a secure, leak-proof interface with standard system piping. This control is an essential component for protecting compressors from low-suction conditions and ensuring stable HVAC system performance in demanding environments.

• Versatile Electrical Configuration: The 4-wire, 2-circuit design allows for simultaneous compressor control and remote alarm notification.
• Rugged Durability: Features an all-steel housing that protects internal bellows and snap-action switches from mechanical damage.
• High-Visibility Monitoring: Integrated sight-set scales enable rapid troubleshooting and precise pressure setpoint verification.
• Broad Compatibility: Standard 1/4" FNPT connection and wide pressure range support a vast array of commercial cooling applications.
• Precise Safety Control: Reliable open-low functionality prevents equipment operation during critical refrigerant loss or suction blockages.

Common Questions

How do I adjust the cut-out and differential settings on the P70GA-11?
Adjustments are made via the internal range and differential screws. The sight-set scale allows you to view the setpoints directly. Always use a calibrated manifold gauge to verify the actual system trip points after adjustment.

What is the purpose of the 4-wire 2-circuit configuration?
This provides two independent circuits. Typically, one circuit handles the heavy-duty motor load (Line-M2) for the compressor, while the second (Line-M1) operates an auxiliary device like a status light or an automated alarm system when a low-pressure event occurs.

Is this pressure control compatible with ammonia systems?
No. The P70GA-11 is designed for non-corrosive refrigerants. For ammonia applications, you must use a specific ammonia-compatible model (typically designated with "SS" or specific "P70L/M" prefixes) that features stainless steel internal components.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.