Abstract: There is provided a combined step and proportional integral flow control valve system having a fluid control valve for controlling flow of fluid into a water stream, a valve motor in operative engagement with the valve for setting the value, a motor control unit having an output connected to the valve motor, and an input responsive to at least one of a first or a second input signal, and wherein the second input signal is a step signal, and the first input signal is a proportional integral control signal. The water stream is a composite of at least one feed stream, a pump is driving the feed stream wherein the water pump includes apparatus for generating the step signal, indicative of the pump being in one of an on or off state. The control valve system includes a flow meter in the water or waste water stream for generating the proportional integral signal as being proportional with the water flow or volume in the water stream.

Abstract: According to the invention there is provided a gas chlorinator with reduced number of components, having a chlorinator housing consisting of a front and a back body forming an interior cavity, a diaphragm assembly disposed between the front and back body dividing the cavity into a front chamber and a back chamber, a chlorine inlet in the back body connecting the back chamber with a chlorine source, a chlorine flow valve in the inlet in operative engagement with the diaphragm assembly for controlling flow of chlorine into the back chamber, a chlorine outlet connecting the back chamber with a vacuum source for activating the diaphragm assembly to supply chlorine to the vacuum source via the chlorine inlet and the flow valve. According to a further feature, the gas chlorinator has matching screw threads formed in the front and back body for threadedly joining the front and back body.