Help with leak

[Shablam]

Good Morning...

Below is a picture of my location of leak. These two pipes are my returns, however I am confused as to why there is a 3 way valve here. I assume one return goes to the pool but what does the other go to?

I have never turned this valve after purchasing the house 4 years ago. Could this maybe be a valve to drain the pool?

I have a leak above this and the only way to repair is to replace the 3 way valve (a 50 dollar part) so I am wondering what purpose this is serving.

 

[duraleigh]

Is it leaking around that union you have covered up with black plastic?

 

[Shablam]

Yes, but its not my black plastic, its the work of the guy before me. He used plumbers tape or something. The union is glued right up to the elbow so the only choice is to replace the whole thing. I have no idea why the guy put these in. It wasnt leaking until now so I had put the project off. Now its un avoidable.

Between the two unions sat a in line puck feeder, and since moving to BBB i took out. I can only guess that he put these in when he installed the feeder. What ever the case my plan is to replace the entire piece with one long pipe up to the 3 way. I just wondered what exactly the 3 way is.


Here is the bigger picture.