Maxitrol M620-1 Gas Valve

For veteran HVACR contractors, the Maxitrol M620-1 stands as the industry standard for precision fuel control in indirect fired atmospheric burner applications. This 1" NPT modulating gas valve is engineered to work seamlessly with the Selectra Electronic Gas Flame Modulating System, providing instantaneous, non-fluctuating temperature control without the need for mechanical linkage or motor-driven butterfly valves. Designed specifically for atmospheric burners, the M620-1 gas valve utilizes a 1/2 PSI maximum inlet pressure rating. Its stainless steel construction and rugged internal diaphragm ensure reliable performance across a wide operating temperature range of -40°F to 125°F. This Maxitrol modulating valve is essential for maintaining consistent discharge air temperatures in makeup air units and space heating equipment where precise gas flow control and high turndown ratios are required. By utilizing a factory-set pressure adjustment spring that maintains outlet pressure slightly above atmospheric, this valve simplifies high-fire and low-fire calibration in the field.

Key Technical Benefits

• Broad Compatibility: Optimally designed for use with Natural, Manufactured, Mixed, and Liquefied Petroleum (LP) gas mixtures.
• Mechanical-Free Modulation: Achieves 0-100% modulation through solenoid-driven magnetic force, eliminating common failure points found in motorized actuators.
• Atmospheric Burner Precision: Specifically calibrated for negative pressure (pull-through) and indirect fired applications requiring stable flame signals.
• Durable Construction: Features a high-grade stainless steel body and UL-recognized safety certifications for professional-grade reliability.
• Easy Installation: Compact 1-inch NPT connections allow for straightforward integration into existing gas manifolds and Selectra control loops.

Common Technical Questions

What is the maximum inlet pressure for the Maxitrol M620-1?
The Maxitrol M620-1 is rated for a maximum inlet pressure of 1/2 PSI (approx. 14" w.c.), making it ideal for standard low-pressure commercial gas lines.

Can the M620-1 be used for direct fired heaters?
No, the M620 series is specifically engineered for atmospheric indirect fired heaters. For direct fired applications, contractors should typically look toward the M411, M511, or M611 series valves.

Does this valve require an external amplifier?
Yes, as part of the Selectra system, the Maxitrol M620-1 requires a compatible electronic amplifier or signal conditioner to provide the DC voltage necessary for modulation.

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.