Other checks (6)

Carefully check by-pass valves and lines
These sometimes leak or are inadvertently left open
A blanking piece is better during operation phase
Inspection: (Contd.)
By-pass valves and by-pass lines are often used for maintenance procedures. In critical situations there may be, for example, two pumps in parallel, in case one breaks down. Additionally, engineers like to be able to replace a pump or a filter without dismantling large sections of the system. However, valves in by-pass lines can leak, be left open, or be contaminated, and so they are undesirable. A “blanking” piece is often better during operation of the system, so that there is no physical connection.