Arizona Plumbing Practice Exam

Which type of joints should not be made using CPVC plastic pipe connections?

1. Heat fusion joints

2. Threaded joints

3. Soldered joints

4. Mechanical joints

The correct answer is: Heat fusion joints

When working with CPVC (Chlorinated Polyvinyl Chloride) plastic pipe connections, it is important to understand the types of joints suitable for this material. CPVC is not designed for heat fusion joints, which are typically used with certain types of thermoplastics such as polyethylene or polypropylene. Heat fusion involves melting the edges of the pipes and fittings together, creating a strong bond as they cool and harden. However, CPVC's characteristics require it to be joined with solvent cement specifically designed for that purpose, rather than through thermal fusion. Threaded joints, soldered joints, and mechanical joints can be employed with CPVC in various applications, making them suitable options for connections. Threaded joints can be used with appropriate adapters, soldered joints are applicable for copper pipes when transitioning between materials, and mechanical joints offer a flexible and demountable connection method. Understanding the compatibility of joining techniques with CPVC is essential for ensuring the integrity and reliability of the plumbing system.