Xylem-McDonnell & Miller 317350 Test & Check Upper Valve w/ Vacuum Breaker TC-U

Description

Xylem-McDonnell & Miller Test & Check Upper Valve with Vacuum Breaker — Model TC-U (SKU 317350)

The Xylem-McDonnell & Miller 317350 TC-U is the upper valve assembly with integrated vacuum breaker designed for use with McDonnell & Miller test and check valve systems. Engineered for hydronic heating and steam boiler applications, this upper valve component provides dependable water feed control, backflow prevention, and vacuum-breaking protection — all in one compact assembly. It is the ideal replacement or service part for existing M&M test-and-check installations, ensuring continued system integrity and code compliance.

Key Features

• Upper valve assembly with built-in vacuum breaker for comprehensive backflow and siphon protection
• Designed specifically for McDonnell & Miller test and check valve systems
• Prevents back-siphonage and negative pressure conditions in boiler water feed lines
• Durable construction suited for the demanding conditions of hydronic and steam heating systems
• Direct OEM replacement — ensures proper fit and function within existing M&M assemblies
• Simplifies maintenance and service by isolating the upper valve for inspection or replacement without full system shutdown

Application

• Hydronic hot water heating systems
• Steam boiler water feed and makeup water lines
• Replacement upper valve for McDonnell & Miller test and check valve assemblies

Brand & Model Information

• Brand: Xylem — McDonnell & Miller
• Model Number: TC-U
• SKU: 317350

Trust Xylem-McDonnell & Miller’s century-long legacy of hydronic and steam control expertise. The 317350 TC-U upper valve with vacuum breaker delivers the reliability and precision that HVAC and plumbing professionals demand for boiler system protection.