DUAL MODE FOAMING SPRAY GUN

A dual mode spray gun has a mixing valve with two inlets and two outlets. A handle assembly extending proximally from the valve couples the first inlet to pressurized water and provides means for manually starting and stopping flow. The second inlet draws detergent from a reservoir mounted to the valve. A barrel extending distally from the valve terminates at spray and foam ports connected respectively to the first and second outlets via first and second channels formed through the barrel, the second channel defining an aeration port upstream of the foam port. A mode switch on the mixing valve in a first position allows flow from the first inlet to the spray port, stops flow from the second inlet and stops flow to the foam port, and in a second position stops flow to the spray port and allows flow from the first and second inlets to mix and aerate en route to the foam port.