Spray washers are almost always fully automated and operate by a CNC system (computer numeric controlled) or PC software. Loading is often done by pick-and-place robotic arms or a conveyor that transfers the parts from a manufacturing operation to the spray washer, which is usually one of the last steps in inline processing.

After the parts have been loaded, they are taken through a wash, rinse, blow and dry cycle. The nozzles spray warm water and water-based solutions, never flammable mineral spirits, which may start a fire or explosion if shot out of a nozzle. The solution is usually set at a temperature of 130º to 190º F, and the spray pressure reaches anywhere from 40 to 60 PSI in order to ensure all grime and contaminants are cleaned from the part surface.

The drying system can consist of either heated air or a simple air blower gun or process dryer, which doesn't use heat. There are many specifications and options when it comes to spray washers, including spray pressure, flow rate, heater power, wash tank capacity, power source type and loading method. Loading methods include front, top or continuous (conveyor belt); spray washers can be built to allow any of the three loading configurations.