Abstract: A programmable fluid or gas control system controls the operation of one or more solenoid valves, each of which in turn controls a gas or fluid dispensing unit. The control system may be used to control water dispensing fixtures such as sprinklers, sinks, showers, toilets and the like, or it may be used in heating-ventilating-air conditioning (HVAC) applications. The control system may have several configurations. In one configuration, a master controller controls one or more slave circuits, which in turn control one or more solenoid valves. Each valve controls at least one gas or liquid dispensing device. The mode of operation of any particular valve and the timing of its operation may be input either via the master controller or via the associated slave control circuit. The operation of the valve may be easily changed without changing hardware or software, allowing the system to be used in a wide variety of applications. In other configurations, the master controller is not used.