Unstable process temperatures may have a hidden cause: steam locking. 

Steam locking occurs when steam enters the trap ahead of condensate, forcing the trap valve to remain closed. This results in condensate backup, reduced heat transfer efficiency, and fluctuating process performance.

The problem is often related to equipment or piping configuration, rather than the trap itself. Examples include:

• Long stretches of narrow piping that allow steam to move ahead of condensate into a trap
• Rotating equipment with siphons that cause steam to mix with condensate in the discharge line

If left unresolved, steam locking can worsen over time. Explore which system configurations are most susceptible to steam locking and learn why hydraulic head pressure alone cannot solve this problem: