Watts 0061935 Preventer

The Watts 0061935 is a professional-grade 1/2 inch dual check valve backflow preventer engineered specifically for continuous pressure, non-health hazard applications. Often cross-referenced as the Watts 9D-M3 or Watts 9DM3-1/2, this unit is identical in fit and function to the legacy 9D-1/2 model. It features a high-durability forged brass body and an intermediate atmospheric vent that provides a visible signal by discharging water if the downstream check valve becomes fouled. This makes it an essential component for boiler feed lines, laboratory equipment, and processing tanks where preventing back-siphonage and backpressure is critical for system integrity.

Designed for versatile field integration, the Watts 9D backflow preventer supports both horizontal and vertical installations. The 1/2" NPT union connections facilitate rapid removal for maintenance without disturbing the main piping. Internally, the valve utilizes stainless steel internal parts and tight-sealing rubber discs—a primary rubber-to-rubber seat and a secondary rubber-to-metal seat—to ensure a reliable 175 psi maximum working pressure. With a temperature rating up to 250°F, this brass backflow preventer is a standard choice for HVAC contractors managing hydronic heating systems and small-scale supply lines.

• Maintenance-Friendly Union Ends: Equipped with union female threaded connections to allow for simplified service and replacement in tight mechanical rooms.
• Atmospheric Vent Protection: Integrated vent port safeguards the potable water supply by exhausting leakage to the atmosphere under fouled conditions.
• High-Performance Internals: Features stainless steel working parts and an integral strainer to reduce check fouling from line debris.
• Compact Forged Design: The forged brass body provides superior strength in a small footprint, ideal for OEM and retrofit boiler applications.
• Flexible Orientation: Verified for performance in either horizontal or vertical installation configurations to meet diverse site requirements.

Is the 0061935 compatible with older 9D-1/2 installations?
Yes, the 0061935 is the modern equivalent and is functionally identical to the 9D-1/2, utilizing the same union connections and 1/2-inch sizing for direct replacement.

Where should the atmospheric vent be directed?
The vent must never be plugged. It should be piped to a floor drain via an air gap to ensure any discharge from a fouled check valve does not cause water damage to the surrounding area.

Can this valve be used on high-hazard chemical lines?
No, the Watts 9DM3 is rated for non-health hazard applications. For toxic substance protection, a reduced pressure zone (RPZ) assembly is required by most codes.

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.