Pressure washing is the use of high-pressure water spray to remove loose paint, mold, grime, dust, mud, chewing gum and dirt from surfaces and objects such as buildings, vehicles and concrete surfaces. The volume of a mechanical pressure washer is expressed in gallons or litres per minute. The pressure, expressed in pounds per square inch, pascals, or bar, is designed into the pump but can be varied by adjusting the unloader valve.
A pressure washer depends entirely on the force of water rather than temperature. Just like a power washer, these are compatible with cleaning patios, decks, walls and walkways but they usually do not feature a heating unit to maintain temperature of the water. Cleaning masonry, brick, concrete is the most suited to a pressure washer. In fact, when there is no mould or ground dirt to contend with, a pressure washer tends to provide a quick and efficient cleaning solution.