A flow sensor module employs a fitting which defines an offset sensor bypass which is disposed at an acute angle to a linear flow path through the fitting. A dynamic pressure or flow sensor is disposed in the sensor bypass. A bonnet assembly is removably mounted to the fitting and mounts the sensor and fluidly seals the sensor in the fitting. A solid state controller has a panel which indicates a number of operational conditions including whether there is fluid flow through the flow system. The panel may have a chemical feed pump default indicator, a control valve indicator and an air trap device indicator and, in one embodiment, a manual override switch to turn on a feed pump, a control valve, an air trap device or an electrically operated device.

A flow sensor module employs a fitting which defines an offset sensor bypass which is disposed at an acute angle to a linear flow path through the fitting. A dynamic pressure or flow sensor is disposed in the sensor bypass. A bonnet assembly is removably mounted to the fitting and mounts the sensor and fluidly seals the sensor in the fitting. A solid state controller has a panel which indicates a number of operational conditions including whether there is fluid flow through the flow system. The panel may have a chemical feed pump default indicator, a control valve indicator and an air trap device indicator and, in one embodiment, a manual override switch to turn on a feed pump, a control valve, an air trap device or an electrically operated device.