How to fix a defect on-off steam valve?

a. Pneumatic pressure too low

To do:

1. Check pneumatic pressure supply
2. Supplied pneumatic pressure must be 4 – 6 bar

b. Solenoid valve defective

To do:

1. Check that the solenoid valve functions, by activating manual override, and checking if air is released when valve is opened/closed
2. If not, follow procedure for solenoid valve defective (“How to fix a defect solenoid valve?“)

c. Actuator defective

To do:

1. Dismount from ball valve
2. Check if it functions when counter pressure is removed
3. Repair or replace actuator.

d. Ball valve defective

To do:

1. Check that ball-valve can be manually opened when actuator is dismounted
2. Clean valve
3. Replace if cleaning is not enough to restore function