When installing CPVC in existing buildings, which procedure must be followed?

• A. Follow manufacturer's cut-in procedures for CPVC.
• B. Use standard piping guidelines for metal systems.
• C. Use any adhesive as long as CPVC is compatible.
• D. Do not follow manufacturer guidelines if not specified.

Answer: (A)

When CPVC is added to an existing building, you must follow the CPVC manufacturer’s cut-in procedures. CPVC uses specific joining methods—typically solvent cement with primers or heat-fusion—that are approved for CPVC and the sprinkler service. These procedures ensure the pipe ends are properly prepared (deburred and cleaned), the correct adhesive or fusion method is used, cure times and temperature limits are observed, and joints are tested for leaks. Using metal-system guidelines or an adhesive not approved for CPVC can lead to weak joints, leaks, or joint failure under pressure. Not following manufacturer guidelines is not acceptable because the listed methods are designed to ensure compatibility and reliability in sprinkler service.