Field Testing, Inspection, and Maintenance
Testing vs. inspection
Field testing verifies mechanical operation (check valve tightness, relief valve opening, air inlet function). Inspection verifies condition, installation, orientation, clearance, drainage, and tagging. Both are required; neither replaces the other.
Test concepts
Know that test procedures follow adopted standards and manufacturer instructions. Understand differential pressure, check valve hold, relief valve opening point, and air inlet operation. Know that test results must be recorded on approved forms with gauge readings, serial numbers, and tester certification. Recognize causes of failure: debris, worn seats, corrosion, freeze damage, improper installation.
Maintenance
Assemblies require repair by qualified personnel, retesting after repair, and record updates. Know freeze protection, drainage, access, and tagging. Understand that a failed assembly must be repaired or replaced and that continued use may require notification to the AHJ.
Traps
- Passing an assembly based on visual inspection alone.
- Using uncalibrated gauges.
- Failing to retest after repair.
- Ignoring orientation and clearance requirements.
Worked example
An RPZ relief valve drips continuously. The tester checks inlet pressure, differential, and check tightness. If the relief opens below the required differential, the assembly fails and must be repaired and retested. Document readings and notify the owner.
Rule of thumb
Test the device, inspect the installation, document both. A passing test on a badly installed assembly is still a program failure.