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Bought a hot tub second hand and I don't think it has any kind of drain valve or anything that allows it to drain through the internal plumbing (just waiting to confirm that from the person I bought it off of). So I'm wondering can you somehow add a means to drain through the existing piping, using one of the water circulation jets without having to drill a hole in the shell to add one? (I wouldn't be comfortable compromising the shell for that). And since it gets very cold here where I live would there be issues with freezing pipes or anything? My plan would be to have it buried underground (a foot or so) and enter the basement through the foundation and drain into the same pipe that my clothes washer drains into. How about filling it again with water through similar means? Siphoning/pumping it outside is a bit of an issue since I live in a dense city neighborhood and we are not allowed to drain pools or anything like that onto the street/back lane. And in the winter it would be a nightmare to try to drain it like that in sub-zero temperatures and 2 feet of snow on the ground.
Siphoning works in the warm months and if you have a big yard with lots of places the water can go but my yard is very small and I have no lawn to drain it on to and in the harsh winter, i'm sorta hooped because I simply cannot drain such a large amount of water onto the street where it will become an icy/slushy hazard. Trying to make this work in a small space in a dense city neighborhood with harsh cold winters is a challenge! My only real option I figure (and nobody has addressed this) is to have an exterior drain pipe sticking out the side of the house close by to the tub that leads to my washing machine drain in the basement that I can drain into. Seems to make sense to me unless somebody thinks that isn't a good idea for some reason.