System Testing & Commissioning
DWV testing methods, water supply pressure testing, final inspection, and commissioning procedures.
- Describe water test and air test procedures for DWV systems
- Explain water supply pressure testing requirements
- Outline the final inspection and commissioning process
Lesson 1
DWV Water Test & Air Test Procedures
DWV Water Test
The water test is the most common and reliable method for testing DWV systems. It verifies that all joints are leak-free before the system is concealed behind walls and ceilings.
Water Test Requirements
- Fill the system to the highest opening (usually the roof vent)
- Maintain water level for the duration specified by code (typically 15 minutes minimum)
- Visually inspect every joint, fitting, and connection for leaks
- Any drop in water level indicates a leak that must be found and repaired
- Retest after repairs
DWV Air Test
The air test is an alternative when a water test is not practical (cold weather, inaccessible locations). Air testing uses compressed air at a specified pressure:
Air Test Caution
Air under pressure stores energy. If a fitting fails during an air test, it can become a projectile. Never exceed the specified test pressure and ensure all plugs and caps are properly secured.
The water test fills the DWV system to the highest opening and checks for leaks visually. The air test uses approximately 35 kPa (5 psi) and holds for at least 15 minutes. Both tests must show zero leaks before the system can be concealed.