Ametek Amrel PLA Series Operation Manual page 149

8) Now the rubber diaphragm has been replaced and the load is ready for operation.
Possible Failure Symptoms
For PLW loads, due to slight solenoid valve factory imperfections or improper usage, the rubber diaphragm of
the water valve may tear after some usage and create a pressure leak. The result will cause a loud vibration
sound, when the water valve is trying to turn on, due to the pressure leak, the valve will be unable to open
properly. Generally, when a loud vibrating noise is heard from water valve during valve turn -on, there may be
a defective rubber diaphragm, to verify please follow the procedures below.
Begin with Steps 1 ~ 4 in previous section, and then continue to Step 9 below.
9) Separate the rubber diaphragm from the metal solenoid assembly.
M470039-01 REV-F Page 148