Hi TFPers - I'm a new homeowner that inherited a large in ground heated pool/spa in the Dallas area. I'm trying to learn more about my new pool system. Currently, there is a leaking plug (see photos) on top of the pipe connecting to the heater. Based on my research it seems like it might be a vacuum relief valve. However, my system is not solar and it seems like those plugs are only used on such systems. Nothing else appears to be leaking and I'm wondering if the leak is impacting pump suction and possibly explaining why my Polaris vacuum seems slow and lazy (often barely moving). Happy to answer any clarifying questions if you can help me figure this one out.
Best!
Best!