Which is a standard step in testing a new cold water installation before commissioning?

• A. Inspecting joints visually
• B. Flushing the line
• C. Purging air
• D. Pressure testing for leaks

Answer: (D)

Verifying that the system can hold pressure without leaking is the essential step in proving a cold-water installation is ready for commissioning. After installation, the system is sealed and pressurized to a specified test pressure (set by local codes and the design) and observed for a defined period. If the pressure remains stable and there are no signs of leaks at joints, fittings, or pipework, the installation passes the test and can proceed to commissioning. Visual checks help catch obvious issues, but they can’t confirm leak-tightness under pressure. Flushing clears debris, and purging air prepares the system for operation, but neither by itself verifies the overall integrity under working conditions.