Zurn 4-450STDA Lead-Free Double Check Detector Assembly, Stainless, Flanged

The Zurn Wilkins 4-450STDA is a 4" lead-free double check detector assembly (DCDA) with Flanged connections, approved for low health hazard protection. It features a stainless body. Rated to 175 psi. This model is certified lead-free for potable-water installations.

The Wilkins 450STDA Stainless Steel n-Pattern Double Check Detector Assembly is ideal for new or direct drop-in replacement, delivering convenience without compromise. Built for fire protection applications, this detector assembly has a metered by-pass to detect leaks and other water use. The patented AR spool offers flexibility in replacing older models with different lay lengths and maintains agency approvals when installed by the factory.

Features

• Superior stainless steel body resists corrosion and extends the life of the product
• Small, compact footprint allows for direct drop-in replacement
• Time-tested check and relief valve components ensure easy maintenance and more water system uptime
• Patented compound checks provide ultra-low pressure drop as documented by approval authorities, reducing the need for a booster pump
• Patented AR spool for drop-in replacements, matching lay-lengths of common n-pattern valves
• AR spool maintains agency approvals when installed by the factory
• Backflow setter eliminates the need for concrete thrust blocks, allowing for easier installation and lower cost
• Available in sizes 4 in. through 10 in.

Common Questions

What hazard level is this DCDA approved for?

It is rated for low health hazard (non-toxic, "pollutant") cross-connections only. Where the downstream substance could be a health hazard, codes require a reduced pressure zone (RPZ) assembly or a detector assembly instead. The assembly is listed to ASSE 1048.

Is this model legal for potable water?

Yes. It is certified lead-free to NSF/ANSI 372, which is what state plumbing codes require for any device in a drinking-water line.

Does this assembly have to be tested every year?

Yes. This is a field-testable assembly. Most water authorities require it to be tested and certified by a licensed backflow tester at installation and annually thereafter. It carries USC FCCCHR approval, which many jurisdictions accept as their sole approval list.

What shutoff valves are included?

It is supplied with non-rising stem (NRS) resilient-seated gate valves on the inlet and outlet.

Is this suitable for a fire sprinkler line?

Yes. Detector assemblies are built for fire sprinkler service: the metered bypass registers the low flows that reveal a leak or an unauthorized tap on the fire line. This model is UL Classified and C-UL Classified and FM Approved. The bypass meter reads in GPM.

Specifications

• Type: Double Check Detector Assembly
• Size: 4"
• Connection: Flanged
• Body Material: Stainless
• Max Pressure (psi): 175
• Application: Fire Protection
• Backflow Protection: Both
• MPN: 4-450STDA
• Certifications: ASSE-1048, AWWA-C510, AWWA-C606, CSA-B64.5, C-UL, UL, FM, USC, NSF-61, NSF-372
• Lead-Free: Yes
• Assembly Type: DCDA
• Hazard Protection Level: Low Health Hazard
• ASSE Standard: ASSE 1048
• USC FCCCHR Approved: Yes
• Fire Protection Listing: UL Classified;C-UL Classified;FM Approved
• Field Testable: Yes
• Shutoff Valves: NRS Gate
• Bypass Meter: GPM