One molder asked me this question the other day…
Our setup techs always seem to connect the water lines incorrectly. We have diagrams to show the setup, but they seem to mess it up anyways.
Companies who use individual water lines rather than a manifold should color-code everything using blue lines for incoming water, red lines for outgoing water, and extra colors such as yellow for line which exit and re-enter the mold.
Once you have this established, place colored plaques on each connection of the mold. This will ensure that your employees cannot accidentally connect an in-line to an out connector.