Johnson Controls P70LA-1 Pressure Control

The Johnson Controls P70LA-1 is a professional-grade Dual Pressure Control engineered specifically for high-reliability commercial refrigeration and HVAC compressor protection. This SPST (Single-Pole Single-Throw) unit integrates both high-side and low-side monitoring into a single device, streamlining field installation for contractors. The low side range covers 20 to 100 psi, while the high side range spans 100 to 425 psi, providing robust safety limits for standard non-corrosive refrigerants. Encased in a rugged NEMA 1 enclosure, the P70LA-1 utilizes a 36-inch capillary with a 1/4-inch flare nut for versatile mounting. Designed for automatic reset operations, this control ensures the system resumes once pressures return to safe operating differentials without requiring manual technician intervention. The Sight-Set calibrated scales allow for precise visual verification of pressure setpoints, though this specific model features no external adjustment knobs to prevent unauthorized tampering or accidental field changes. This pressure limiting control is a standard replacement for maintaining system equilibrium and preventing compressor failure due to extreme pressure fluctuations.

• Dual-Function Monitoring: Combines high-side and low-side pressure protection in a single NEMA 1 enclosure to save space and reduce wiring complexity.
• Automatic System Recovery: Integrated automatic reset functionality ensures equipment uptime by re-engaging the compressor immediately after pressures stabilize.
• Tamper-Resistant Design: The lack of external adjustment knobs prevents site occupants from altering critical HVACR pressure settings.
• Durable Construction: Features an all-steel case and PENN dual pressure bellows designed to withstand high-cycle environments in commercial applications.
• Simplified Installation: The included 36-inch capillary provides the reach needed for various refrigeration pressure control manifold configurations.

Is the Johnson Controls P70LA-1 compatible with ammonia refrigerants?
No, this model is designed for use with non-corrosive refrigerants. For ammonia applications, a specific corrosion-resistant model such as the P70LA-2 must be used.

Does this unit require a manual restart after a high-pressure trip?
This specific pressure switch is an automatic reset model. It will automatically close the circuit once the system pressure falls back within the differential range.

Can the pressure setpoints be adjusted without the knob?
Yes, setpoints can be adjusted using the internal range screws visible through the cover; the "no knob" design is intended to deter tampering, not to eliminate adjustability for qualified technicians.

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.