Pentair SunTouch® 520819 Solar Control System with 3-Way Down Drain Valve. With the touch of a few buttons, you can quickly program your pool and spa filtration and heating cycles to fit your schedule. With SunTouch®, your pump and heater automatically run whenever you want, for as long as you want so your pool and spa are always warm and inviting. The standard SunTouch® package has the ability to schedule operation of additional functions, such as your lights or automatic cleaner.