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After all the discussion recently on the warranties and repairs and modifications, I'd bet that putting a chiller (it's a very good idea, though!) would be looked upon as a modification that would have un-designed consequences, and anything that went wrong, from leaks (temperature changes?) to electronics (temperatures changes? ) to cracks (guess what...) would have an easy place to point a finger at. (Whether or not the choller/cool water actually did do anything, of course.)I do wish there was a high end spa that had a cooler/cooling option so that you could easy keep the water at, say, 85 or 90, when it's 95-100 outside.