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We have the "freeze-free" spigots too. The one by my tub is also in the sun. So far, so good.Double check your water softener info. Ours was specifically hooked up so that only hot water was run through the softener. I don't think you'd want to be drinking that stuff on a regular basis. :-? I just assumed that all were set up that way.That's why when we boil water for noodles, we fill up with cold instead of hot--you don't want the extra salt.Check your kitchen/bathroom faucets for deposits around the base. That would let you know that your cold water is hard.