Sorry, I know this isn't exactly plumbing related to inside a house but I have an issue with my inground pool plumbing when I'm trying to winterize it.
We bought this house from someone a few years ago (short sale) and evidently they didn't winterize it well enough which led to a cracked line. Our pool has two lines running to the pump. One from the skimmer box and one from the bottom of the pool. They are both dedicated lines and both need to be blown out and sealed at the end of each season.
I've fixed the crack issue (fortunately it occured right below the concrete patio where I thought it was so I lucked out there.)
Two years later though, that lower line is a pain to clear and keep air tight. As shown in image at the pump there is a ball/union valve for this dedicated line. I've replaced all the rings and washers once already because the original stuff was all scratched up and wouldn't hold air. I already notice after one season small scratches on the ball surface and worry it will let air out over the winter season and recrack the line. I want to come up with a solution that I can rely on and be easier to seal. Currently I open the ball valve, place an air line from compressor into the opening and shut off the valve as quickly as I can once air bubbles start coming from the bottom of the pool drain.
My current thought is to remove the ball valve which leaves me the threaded end of the union which is solvent welded to the line. Then screw on "something" that has a one way valve like a schraeder valve or something so I can fill it with air and not worry about it again. Then just remove this ghetto unit when I open the pool and put it in storage for next year.
Anyone have any ideas on how to do this or any better ideas? I've searched the internet but can't find anything that fits my need.