PRESSURE WASHERS
A pressure washer is a mechanical sprayer that, depending on nozzle size, can be used as a low volume high-pressure water cleaner or a high volume low pressure water cleaner to remove loose paint, mold, grime, dust, mud, and dirt from surfaces and objects such as buildings, vehicles, and concrete road surfaces.
The basic pressure washer consists of an electric motor or gasoline (petrol) engine that directly drives a water pump, a high-pressure hose, trigger gun-style switch.
Two types of chemical injectors are available — a low-pressure injector that introduces the chemical after the water leaves the pump (a downstream injector) and a high-pressure injector that introduces the chemical before water enters the pump (an upstream injector). The type of injector used is related to the type of detergent used, as there are many chemicals that will damage a pump if an upstream injector is used.