Mueller Industries A17934 Check Valve

When you're dealing with high-pressure refrigeration cycles, backflow isn't just an inefficiency—it's a risk to the compressor. The Mueller Industries A17934 is a 1/4" Magnetic Check Valve engineered for technicians who need a zero-fail solution in HVACR refrigeration systems. Built with a hermetically sealed copper body, this CHECKMASTER® series valve utilizes a magnetic closure mechanism rather than a traditional heavy spring, allowing for a low pressure differential to open (<1 psig) while ensuring a positive seal even with minimal back-pressure. Designed to handle a maximum working pressure of 800 PSI and operating temperatures from -40°F to 300°F, the A17934 is fully compatible with modern refrigerants including R410A, R134A, and R404A. The internal stainless steel screen protects the seat from debris, making it a reliable choice for liquid lines or hot gas discharge where backflow prevention is critical.

• Full Refrigerant Compatibility: Optimized for use with POE, mineral, and naphthenic oils, supporting a wide range of gases including R22, R32, R410A, and R1234yf.
• High Durability Construction: Features a copper body with an aluminum internal disk holder and a stainless steel magnetic disk for superior corrosion resistance and longevity in the field.
• Minimal Internal Leakage: Performance tested to maintain a leak rate of less than 2.3 ml/min, ensuring strict pressure control and system efficiency.
• Simplified Installation: The 1/4 inch ODS connection and compact inline valve design allow for easy brazing in tight mechanical footprints.

What is the primary advantage of a magnetic check valve over a spring-loaded version?
Standard spring check valves often require significant pressure to stay open, which can lead to chattering and premature wear. The magnetic design of the Mueller A17943 provides a much more consistent flow with a lower pressure drop, reducing turbulence and noise in the line.

Can this valve be installed in any orientation?
Yes, the magnetic closing force is consistent, allowing for vertical or horizontal installation. However, as with all refrigeration check valves, ensure the flow arrow on the body matches your system's direction of travel.

Is this valve suitable for high-pressure CO2 systems?
While the 800 PSI pressure rating is sufficient for many standard applications, always verify your specific system peak pressures. For sub-critical CO2 or high-pressure R410A discharge lines, the A17934 provides a robust UL recognized safety margin.

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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.