Johnson Controls P47AA-13 Pressure Control

As a heavy-duty steam pressure limit control, the Johnson Controls P47AA-13 is engineered for high-limit or operating control applications in commercial and industrial steam heating systems. This SPST pressure switch features an "open on rise" configuration, ensuring the circuit interrupts immediately when steam levels exceed your setpoint. With a broad 0 to 150 psig pressure range and an adjustable 12 to 50 psi differential, this unit provides the precise calibration required for demanding boiler environments. The robust bellows sensing element is compatible with steam, air, water, and non-combustible gases, while the 325 psi maximum allowable pressure offers a substantial safety margin. Built for efficiency, the automatic reset functionality eliminates manual intervention after pressure stabilizes. Designed for versatile integration, the electrical ratings support 120, 208, 240, and 277 Vac, allowing for seamless installation across various power configurations. The internal 1/4 in. NPT connection and dual "sight-set" scales make field adjustments straightforward for any seasoned technician.

Key Benefits

• High-Pressure Versatility: Handles up to 150 psig with a high 325 psi overpressure limit for superior system safety.
• Precision Control: Features a 12 to 50 psi adjustable differential to prevent frequent equipment cycling.
• Durable Construction: Long-life contact structure with high contact force ensures reliable switching in harsh HVACR conditions.
• Simplified Calibration: Dual sight-set scales allow for quick visual verification of both cut-in and cut-out settings.
• Wide Compatibility: Suitable for use with steam, water, and air without damaging internal copper or brass components.

Common Questions

What is the maximum electrical load for the P47AA-13?
This control is rated for a 16.0 Amp full load at 120 Vac and 9.2 Amp at 208 Vac, supporting a wide range of line voltage applications.

Can this be used on liquids or gases other than steam?
Yes, the P47 series is compatible with air, water, and other non-combustible fluids as long as they are not harmful to iron, copper, or brass.

Does this unit require a siphon for installation?
Standard industry practice requires a siphon for all steam applications to prevent live steam from entering the bellows, protecting the integrity of the pressure control switch.

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.