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Most quality spas have relatively sophisticated digital thermostatic controls. These highly reliable modern systems are capable of keeping the spa water within one degree of any temperature you select. While this is important for comfort, it is also important for safety. You should pay particular attention to the control system if you have children who will be using the spa. Better systems have safety locks and digital readouts. A good indicator of the control system's quality is to read and compare manufacturers' warranties.
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