Paramount 004-302-4408-00 6 Port Water Valve Module with Valve Shell O-Ring
You will know when you have to replace this water valve module when:1: Valve sticks on the same cycle
2: More than one zone in the pool is up
There are no individual parts to replace in this module, you must replace the whole module, but it is super easy to replace.
Step 1: Take off the band clamp
Step 2: Take the dome off the water valve
Step 3: Pull the "Bad" module out of the Water Valve Base; it will pull straight up
Step 4: Replace the new module back into Water Valve Base. Tip: It doesn't matter what possition the new module goes into the base
Step 5: Inspect and lubricate Oring
Step 6: Replace the dome and the band clamp
Every unit is pressure tested before leaving the Warehouse. If there is water still in the bag (Of the Paramount Module) don't be alarmed, the module most likely has been tested within a few days. 
High quality replacement 
