Mueller A17940 Check Valve

For field technicians and mechanical contractors, the Mueller A17940 stands as a heavy-duty 1 1/8 magnetic check valve engineered to eliminate backflow in critical refrigeration and air conditioning circuits. Part of the Mueller CHECKMASTER series, this valve utilizes DuraForm technology to secure internal components without the use of braze materials. This manufacturing process prevents the overheating and warping often associated with traditional assembly, ensuring the hermetically formed solid copper body maintains a zero-leak profile. With a maximum operating pressure (MAP) of 800 psig and a temperature rating from -40°F to 300°F, it is fully compatible with CFC, HCFC, and HFC refrigerants, including high-pressure R-410A systems. The magnetic lift mechanism replaces standard springs to provide near-zero internal leakage and a low pressure drop, while the integrated 30 mesh stainless steel screen protects the seating surface from systemic debris.

• DuraForm technology eliminates internal braze material for superior structural integrity during high-heat installation.
• Features a 1 1/8 ODS solder connection with mechanically formed stops for fast, precise fit-up.
• High-capacity 800 PSI rating makes it suitable for liquid, suction, or hot gas defrost lines.
• Equipped with a built-in 30 mesh screen to keep the magnetic seat clear of contaminants.
• Flexible installation allows for vertical or horizontal mounting to fit tight mechanical room footprints.

• Can this be used on the discharge line of a rack system? Yes, the A17940 is specifically designed for commercial refrigeration discharge and liquid lines where positive isolation is required.
• What is the cracking pressure? This magnetic valve is engineered for a low pressure differential to open (typically less than 1 psi), maximizing flow efficiency.
• Is it compatible with POE oils? Yes, it is fully compatible with Mineral, Naphthenic, and POE oils used in modern HFC systems.

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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.