As the angle decreases, each location's energy begins to climb once more. They sport a motor, a pump to drive water through a hose, and a constricted nozzle which speeds the water as it escapes, providing much of the impact force with which it hits the surface. There are accessories galore, and they can all make a job easier, quicker, and more profitable. But a modified or adorned pressure washer by any other name is still a pressure washer. Even without calculating the impact force, it's fairly easy to determine how much power a machine brings to the jobsite.
Every pressure washer carries a flow-rate capacity and a pressure capacity.
The higher these numbers, the higher the impact force and the higher the available cleaning energy. But, said Robert Hinderliter, owner of Delco Cleaning Systems in Fort Worth, TX, what many contractors don't know is that increasing the water is just as effective as increasing the pressure. A lot of the people who fail also fail because they look only at pressure. Graco's Ken Krieter agrees. Krieter explained that the impact force of a pressure washer set at 1,000 psi and 2.6 gpm can be doubled by increasing the flow to 5.2 gpm.