CPVC Union — 3/4 in. Socket — Spears FlameGuard™ — 4257-007
The Spears FlameGuard™ 3/4-inch CPVC union allows two sections of CPVC pipe to be connected and easily disconnected for maintenance or replacement in wet fire sprinkler systems. Made from fire-protection-grade CPVC, it resists corrosion and provides a durable, watertight connection. The solvent-cemented socket ends are joined using ASTM F493-approved solvent cement for a permanent, secure seal. A precision-molded union nut allows the fitting to be tightened or removed without cutting the pipe. The fitting is UL Listed and FM Approved for use in systems that meet NFPA 13, NFPA 13R, and NFPA 13D. Rated for 175 psi and a maximum temperature of 150°F, this union is ideal for residential and light-hazard applications.
Follow Spears FlameGuard™ instructions for proper pipe cleaning, cementing, and assembly. The union should be hand-tightened and checked for leaks after system pressurization. It’s important to use only approved CPVC sealants and to avoid overtightening, which could damage the threads. This fitting provides a reliable, code-compliant solution for connecting and servicing CPVC fire sprinkler piping while maintaining full compliance with UL, FM, and NFPA standards.

