We recently had a pool build and finished construction mid July of this year. Per the contract the pool co. is responsible for the first closing etc. I worked with them to close the pool so I had an idea of how it was done. Basically what they did was hook up a compressor to a plug in the bottom of the Pentair pump and let it blow through every inlet and return. One by one they plugged each pipe penetration. Until everything was plugged and no more air escaping. And where they couldnt plug the inlets in the bottom of the pool they blew air until air was releasing from the bottom and closed the valve to air lock the pipe. They then removed all the heater plugs and sand filter plug and booster plug. Very little water was in the system at this point. I feel my pipes are safe, what I am worried about is the fact that they didnt drain the pool down. They said they have more problems with the weather freezing and cracking the plaster and also leaving a ring on the plaster when it comes time to open. I also have a sun self about 7 inches down. If I were to drain below the skimmers, it would leave this exposed all winter. I actually forced the guy to let me waste water to just above the plaster so the water was just on the tile accommodating rain. Everything I read here says the pool needs to be drained below the tile. I figure I will let it go this year since its there warranty and they will have to cover, but am I wrong in thinking it needs to be below the tile? Thanks in advance.