Hayward Aqua Solar control system with LV/HV output and time clock 3-horsepower relay is quick, accurate, easy-to-set desired temperature control. Automatically maximizes solar heat collection. Precise, easy-to-read, calibrated temperature setting. Electronics in UV-protected locking weatherproof enclosure. LED indicators show status of system operations. Automatic switching (selectable) from solar pool heating to nocturnal pool cooling. Single-setting adjustment for desired pool/spa temperature.