We are not the original owners of this pool, but have been caring for it successfully for about 9 years. We received a crash course from previous owners. 4 returns, no main drain, two skimmers.
We do not know what this spigot is or what happens if we turn it. We have bubbles in our return and are trying to determine where the air comes in the system at. This thing scares us. I can't remember why it is wrapped in electrical tape.
First picture is a closeup. Second shows its placement in the system.
Thanks in advance for any clues you can give me!