I just inherited a 1988 Sundance Supra spa with a Sentry #605 control system. The wiring came in a separate box. I have restored all wiring but the freeze control..........can't find the location of that. I also have one wire with the temperature sensor on the end. I don't know where the sensor needs to be located in order to function properly.

The unit was said to be having problems with the heating cycle when last operational. Since I am new to working on spas/hot tubs any information/advice would be greatly appreciated.

Thanks in advance.