I've had a coleman 400 series spa for eight years. In the past year I haven't used our spa at all, and would like input on disconnecting the power and drainage of the spa. I worry about what will happen to spa in the desert extremes (AZ), but have an equal amount of problems with it running($$). Probably going to try to sell eventially. Any suggestions on dry storage??

I also have a coleman horizon 400. I drained it before this winter and have been checking on it (inside of cabinet) every few weeks, and everything seems fine so far. I live in Chicago and our winters get pretty fu***n cold. And lots of snow. I completely drained hot tub then opened the unions connecting to both pumps. Total of 4 unions. Disconnected union to heating element and lower all pipes to completely drain. It will drain for another 3-5 minutes for there still is about 10-12 gallons of water remaining in the pipes. Take a shop vac and either suck out or blow out all your lines. Make sure you keep your hot tub covered for protection. Now I've heard of people leaving a small amount of water at bottom of hot tub to create humidity inside of tub so jet gaskets don't completely dry out and shrink or break apart. Like I said I've been checking on it every couple of weeks and my tub has been ok so far
Hope this helps,
Robert