Help Identifying Piece of Plumbing


New member
Jul 5, 2019
Boxford, MA
Hello. I purchased a home with an inground pool at the end of last summer and am now attempting to open it for the first time. The pool uses an Autopilot SWCG system. Before starting the opening process I removed and cleaned both the salt cell and union screen. After removing the union screen I noticed a loose piece of plastic plumbing resting at the bottom of the pipe below where the union screen sits. The piece is conical in shape with a 1.5 inch diameter at its widest point. There are a few nicks and rough spots along its rim but no jagged edges or any other evidence that would suggest it broke off another piece of plumbing. Attached are a few pictures I took of the piece and the location of where I found it. Does anyone have an idea of what this could be? If it's a vital piece of the pool plumbing I want to make sure to get it repaired or replaced prior to opening. Thanks in advance.


  • 20200507_170736.jpg
    362.5 KB · Views: 33
  • 20200507_170730.jpg
    353 KB · Views: 31
  • 20200507_170819.jpg
    318.1 KB · Views: 31
  • 20200507_170859.jpg
    158.7 KB · Views: 34
  • 20200507_170656.jpg
    286.8 KB · Views: 36

Pool Clown

In The Industry
Sep 5, 2008
Silicon Valley, CA
To all who read the following:
This is not an invitation for argument.

It has been the practice that a check valve be plumbed in just upstream of the Chlorinator, or somewhere in between the heater and the chlorinator to keep concentrated chlorine from flowing backwards into the heater and causing corrosive damage after the filter pump shuts off. The fact is, once the pump shuts off, electricity to the chlorinator is also shut off halting chlorine production. In the event that the chlorinator is not wired to the filter pump but rather wired directly (always on), the unit also has a flow switch that would turn the unit off when no flow is detected, i.e., same outcome. And since there would be no corrosive buildup of chlorine, there is little use for a check valve at that location. But since i am a warranty station for several SWCG manufacturers, i am obligated to say, yes, there should be a check valve there.

Note: The above relates to salt water chlorine generators only! Erosion feeders and injection types DO NEED check valves.
Last edited:
  • Like
Reactions: RDspaguy
Thread Status
Hello , This is an inactive thread. Any new postings here are unlikely to be seen or responded to by other members. You will get much more visibility by Starting A New Thread