Maxitrol 325-5-1/2-12A39 Regulator

The Maxitrol 325-5-1/2-12A39 is a high-performance lever acting gas regulator engineered for 2-PSI piping systems and high-pressure house lines. This 1/2" NPT unit is designed for precision pressure control in multi-family residential, commercial, and industrial applications. Capable of handling a 325,000 BTU/hr max capacity, it manages a maximum inlet pressure of 5 PSI for natural gas and 2 PSI for LP applications. The positive dead-end lock-up feature ensures a tight seal during no-flow conditions, preventing downstream pressure creep and protecting sensitive equipment. The factory-preset 4" to 12" W.C. outlet pressure range provides the versatility needed for various burner manifolds. Equipped with a 12A39 vent limiter, this regulator eliminates the need for vent piping to the outdoors when local codes allow, simplifying installation in tight mechanical rooms. Its rugged aluminum construction and high-grade internal components ensure long-term reliability in demanding HVAC gas piping environments.

Key Performance Benefits

• High Pressure Capability: Rated for up to 5 PSI inlet pressure, making it ideal for 2 PSI gas piping systems.
• Integrated Vent Limiter: Includes the 12A39 factory-installed vent limiting device for indoor installation without external vent lines.
• Dead-End Lock-Up: Provides a bubble-tight shut-off to protect downstream components from over-pressurization.
• Precise Regulation: Lever-acting design provides superior low-pressure gas regulation and response time during high-demand cycles.
• Compact Footprint: 1/2" NPT connections allow for seamless integration into existing natural gas manifold configurations.

Common Technical Questions

Can the 325-5-1/2-12A39 be mounted in any orientation?
For proper performance and to comply with the 12A39 vent limiter requirements, the regulator should be installed in a horizontal upright position. If installed in other orientations, the vent limiter may not function as intended by the manufacturer.

Is this regulator suitable for outdoor use?
While the 325 series is durable, if installed outdoors, the vent limiter must be removed and the vent port must be protected from weather, debris, and insects to prevent clogging or corrosion of the internal diaphragm.

What is the lock-up pressure for this model?
The lever-acting design is specifically engineered for positive dead-end lock-up, meaning the outlet pressure will not rise significantly above the set point when the appliance gas valve closes.

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.