Journeyman Plumber ExamWater Supply SystemsEasy
A plumber is preparing to install new copper water distribution piping in a residential renovation. Which of the following methods is NOT an approved or common joining method for copper water tubing in potable water systems, according to most plumbing codes?
- ASoldering (sweating) with lead-free solder.
- BMechanical fittings (e.g., press-connect or compression).
- CSolvent cementing with PVC primer and cement.
- DBrazing with appropriate filler metals.
Show answer & explanationAnswer & explanation
Correct answer: C. Solvent cementing with PVC primer and cement.
Solvent cementing is a joining method exclusively used for plastic piping materials like PVC or CPVC, not copper. Attempting to solvent cement copper tubing would not form a watertight or structurally sound joint and is not permitted by any plumbing code for copper.
Why the other options are wrong
- A. Soldering with lead-free solder is a very common and approved method for joining copper potable water piping.
- B. Mechanical fittings like press-connect or compression fittings are approved and increasingly common methods for joining copper tubing.
- D. Brazing provides a stronger joint than soldering and is an approved method, especially for higher pressure or temperature applications.
Copper Pipe Joining Methods
Approved techniques for creating secure, watertight connections between copper pipes and fittings in potable water systems, typically involving heat, mechanical means, or specialized adhesives.
- Lead-free solder is mandatory for potable water.
- Brazing offers higher strength.
- Mechanical fittings provide flameless options.
Memory trick: Copper joins with heat, mechanical, or press, but never a plastic's messy stress.