Seems like there are some problems with it though still! The thread is a bit stale but you may want to have a read or post there to see if it would work for your application.
A Hot Springs Salesman talked me out of it. He recommends leaving the tub at 102 F. He pointed out that if I lowered the temp to say 50 and the power went out that it would not take to long for freeze problems to occur. Also it is hard on the heater to bring the temps up and down. If you forget to turn up the heat then you have to wait. And the tubs are much more energy efficient.
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