Hello, I purchased a house with a pool/spillover spa. In the middle of the spa was a 1 1/2" PVC pipe that went from the a threaded fitting in the floor of the spa to the water surface of the spa making it kind of impossible to use the spa. I decided to remove the "stand pipe" and test out the operation of the pool and spa. Nothing different happened and it appeared to function the same as before. However, I would like to know what this is. I also have a pool leveler (labeled valve at the equipment pad) but no obvious outlet or float switch in either of the skimmer boxes. I turned on the leveler valve but nothing came out of any oriface or pipe (I verified that there was water in the piping because the valve leaks). Not sure if these are related but they both seem strange. I installed a new spa heater because the existing wasn't working when I moved in. Now the new heater is having flow related error codes.