This hot tub is 20yrs old but in mint condition I don't know what the numbers 1-3-5-7-9 mean. The tub is a Hot Springs Jet setter 2 seater made in the 2ed quarter of 1989. I can set the dial one notch above the number on 1 and the heater will cut off exactly 100* degrees. Lamar

Good job having a HotSpring.

Those are just numbers to give you a gauge as to where to set it. I have a '91 Classic and I mark where my 100 degrees is on the dial - a red dot for summer and blue for winter. They are just numbers on a dial - it doesn't correspond to any temperature.

Pete
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