Pressure Washer Glossary
Adjustable Pressure Regulator - Varies the pressure of the high-pressure spray.
Adjustable Spray Wand - Some models are equipped with an adjustable spray wand. Rotating the tip will adjust the pattern.
Automatic Cool Down System (Thermal Relief)Cycles water through pump when water reaches 140° - 145° F. Warm water will discharge from pump onto ground. This system prevents internal pump damage.
Axial Cam - A device (cam) used to transform the rotary motion of the motor/ engine into the reciprocating motion of a pump's pistons.
Chemical Injection System - Cleaning solutions are drawn into water stream to make cleaning more effective by allowing solutions to saturate the soiled surface at low pressure.
Cleaning Units (CU) - A measurement used to indicate cleaning power. Cleaning units are the results of the following equation: PSI X GPM = CU OR 2200 PSI X 2.0 GPM = 4400 Cleaning Units
GPM - Gallons per minute. A unit of measure for water flow.
High Pressure Outlet - Connection for high pressure hose.
HP - Same as horsepower, a unit of measure for work
OHV - Same as 'overhead valve', an improved way to control exhaust and intake valves on internal combustion engines.
OHVI - An industrial, more durable version of the OHV engine.
PSI - A unit of pressure, same as 'pounds per square inch'.
Purge - A method of eliminating air from a pressure washer so that starting the engine is easier
RPM - Same as revolutions per minute. The amount of revolutions (turns) an engine makes in one minute
Side Valve - A type of internal combustion engine that uses a conventional "L" type cylinder head with the exhaust and intake valves on the side of the engine.
Spray Gun - Controls the application of water onto the cleaning surface with a trigger.
Thermal Relief - A technique used to reduce the build-up of high temperature water within a pressure washer pump caused when the spray gun trigger is closed.
Turbo nozzle - A device used to increase the effectiveness of high-pressure water, by spinning a narrow stream of water in a circle at a high speed.
Unloader - A device used to relieve the water pressure within the pump whenever spray flow is blocked