Zurn 4-350OSY, Ductile Iron, Flanged

The Zurn Wilkins 4-350OSY is a 4" double check valve assembly with Flanged connections, approved for low health hazard protection. It features a ductile iron body. Rated to 175 psi and up to 140°F.

Common Questions

What hazard level is this Double Check 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 1015.

Does this assembly have to be tested every year?

Yes. This is a field-testable assembly with 4 test cocks. 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 outside screw and yoke (OS&Y) gate valves on the inlet and outlet. OS&Y gates give the visible open/shut indication that fire-line and many water-authority specs require.

Is this listed for fire protection service?

Yes -- it is UL Classified and C-UL Classified and FM Approved, the listings normally required for a backflow device on a fire sprinkler supply.

Specifications

• Size: 4"
• Connection: Flanged
• Body Material: Ductile Iron
• Max Pressure (psi): 175
• Application: Domestic Water
• Backflow Protection: Both
• MPN: 4-350OSY
• Temperature: up to 140°F
• Certifications: ASSE-1015, AWWA-C510, AWWA-C606, CSA-B64.5, C-UL, UL, FM, USC, NSF-61, NSF-372, IAPMO
• Assembly Type: Double Check
• Hazard Protection Level: Low Health Hazard
• ASSE Standard: ASSE 1015
• USC FCCCHR Approved: Yes
• Fire Protection Listing: UL Classified;C-UL Classified;FM Approved
• Field Testable: Yes
• Number of Test Cocks: 4
• Shutoff Valves: OSY Gate