Maxitrol R400S-3/8-CSA Regulator

The Maxitrol R400S-3/8-CSA is a high-performance gas pressure regulator engineered for precision fuel control in commercial and industrial HVACR applications. Built with a 3/8" NPT pipe size, this double diaphragm balanced valve design ensures stable outlet pressure even when upstream pressures fluctuate, preventing pilot dropouts and burner instability. The unit carries a CSA certified max inlet pressure of 1/2 PSI, though it has been Maxitrol tested up to 5 PSI for robust handling in demanding environments. With an adjustable outlet pressure range of 3-6" w.c., this multi-poise regulator can be mounted in any orientation except upside down, making it a versatile natural gas and LP regulator for tight equipment manifolds. The aluminum die-cast body provides superior durability while the internal vent limiting device adds a layer of safety for indoor installations where external vent piping may be restricted.

• Double Diaphragm Design: Eliminates the need for external vent lines in specific applications while maintaining superior regulation sensitivity.
• Balanced Valve Construction: Neutralizes the effect of inlet pressure variations, ensuring a consistent 3-6" w.c. output for optimal combustion.
• Flexible Mounting: The multi-poise capability allows for horizontal, vertical, or angled installation without compromising flow characteristics.
• High-Capacity Flow: Specifically designed for high-load cycles common in commercial burners and industrial gas trains.

Can the R400S-3/8 be used for propane (LP) applications?
Yes, this regulator is suitable for natural gas, LP gas, and air/vapors. Ensure the specific gravity of the gas is accounted for when calculating flow capacity.

Is an external vent line required for the R400S series?
The R400S features an internal vent limiting means. However, local codes should always be consulted to determine if physical venting to the outdoors is required based on the installation environment.

What happens if the inlet pressure exceeds 1/2 PSI?
While CSA certified for 1/2 PSI, the unit is Maxitrol tested for emergency exposure up to 5 PSI. Exceeding these limits consistently can lead to internal diaphragm stress and erratic regulation.

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.