Johnson Controls P-3800-2 Controller

The Johnson Controls P-3800-2 is a professional-grade Reset Volume Controller engineered for precise airflow regulation in Variable Air Volume (VAV) systems. Designed as a pressure-independent submaster device, it maintains accurate volume control between adjustable minimum and maximum setpoints in response to a thermostat or master controller signal. This unit supports a 13-25 PSIG supply pressure range and operates with a primary input capacity to handle velocity pressures as low as 0.01 in. WG. For contractors, the dual-acting capability (DARR/RADR) simplifies inventory, as it is compatible with various NO/RA or NC/DA VAV box and thermostat configurations. The 3/8" barbed fitting air connections on Inputs I and II ensure a secure pneumatic hookup, while the 25 SCIM air consumption rating optimizes system efficiency. The reset start point is factory-calibrated at 3 PSIG but remains fully field-adjustable between 3 and 10 PSIG to meet specific site mechanical schedules and balancing requirements.

• Universal Application: Dual-configuration support (Direct Acting and Reverse Acting) allows for use in both heating and cooling VAV setups.
• High Sensitivity: Maintains stable volume control even at low velocity pressures down to 0.01 in. WG (2.5 Pa).
• Durable Construction: Built with high-grade Noryl housing to ensure stability and resistance to mechanical shock in commercial environments.
• Simplified Integration: Features an isolated diaphragm design that accepts various sensing line diameters without compromising accuracy.
• Standardized Fittings: Equipped with industrial-standard 3/8-inch barbed fittings for reliable connection to pneumatic tubing.

What is the maximum supply pressure for the P-3800-2?
The unit is rated for a supply pressure range of 13 to 25 PSIG (91 to 175 kPa). Operating outside this range may impact the output accuracy or signal stability.

Can the reset start point be modified in the field?
Yes. While it is factory-set at 3 PSIG, the reset start point is fully adjustable from 3 to 10 PSIG to align with specific system design parameters.

What type of thermostat action is required?
This pneumatic controller is compatible with both direct-acting and reverse-acting thermostats, providing flexibility for diverse VAV/thermostat configurations.

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.