Testing, Leak Detection & Commissioning
Pressure testing, leak detection methods, line purging, combustion analysis, appliance commissioning, and flue gas measurement.
- Describe gas piping pressure test procedures and acceptance criteria
- Identify leak detection methods and their proper application
- Explain line purging procedures and safety requirements
- Perform combustion analysis and interpret flue gas readings
- Describe appliance commissioning procedures and documentation
Lesson 1
Gas Piping Pressure Tests
Why Pressure Testing Is Required
All new gas piping and any piping that has been modified must be pressure tested before being placed in service. The test verifies that all joints, fittings, and connections are gas-tight and safe for operation.
Test Requirements
| Test Type | Medium | Pressure | Duration |
|---|---|---|---|
| Low-pressure piping | Air or inert gas | 3 PSI minimum | Per local code |
| High-pressure piping | Air or inert gas | 1.5x operating pressure | Per local code |
Never Test with Gas
Pressure testing must be performed with air or inert gas (nitrogen) - never with natural gas or propane. Testing with fuel gas creates an explosion hazard if a leak exists. Oxygen must also never be used as a test medium.
All new or modified gas piping must be pressure tested with air or inert gas before service. Low-pressure tests use a minimum of 3 PSI. Never test with gas or oxygen. Any pressure drop indicates a leak that must be found and repaired.