We just had our pool resurfaced. I stupidly never checked that the installer replaced the output valve exactly as it was before now. Trying to close our pool for the winter and realize that the output valve [that I have a threaded cap for] is now UNTHREADED and completely different. I guess they put something new on after resurfacing. Of course, the installer isn't getting back to me. What kind of plug should I be looking for? Unthreaded, of course. argh.