What is the most reliable method to test if a trap is working properly?

Touching the body of the trap is a common and effective initial method for checking if a steam trap is functioning correctly. When assessing a steam trap, a technician will typically feel the temperature of the trap body. If the trap is working properly, the inlet side should be warm, while the outlet side should be cooler, indicating that condensate is being expelled efficiently. A significant temperature difference implies that the trap is allowing steam to escape and is not clogged.

This method is practical and does not require additional equipment; however, it should be coupled with more comprehensive diagnostic methods for a thorough assessment. While checking the pressure gauge, listening for sounds, and measuring flow rates can also provide useful insights into a trap's performance, touching the trap gives immediate physical feedback about its operation, making it the most straightforward and reliable preliminary test.