Abstract: Electrical control circuitry is provided for normally maintaining an electrically controlled water supply valve in an open condition and an electrically controlled water drain valve in a closed condition when a home is occupied and for arming the system by shutting off the water supply valve and for maintaining the water drain valve in an open condition. This action prevents pipe bursting and flooding, particularly during the winter, when a single manually operated conspicuously located switch is opened to arm the system upon departure from the home for an extended period. Should the home owner forget to arm the system, an electrical power interruption, which often can disable heating systems, causing pipe bursting and flooding, will automatically arm the system upon a power failure and the supply valve remains shut and the drain valve remains open until the homeowner returns and resets the system with a pushbutton switch.