DeWalt DXPW4240 Instruction Manual page 19

Chemical injection system: Mixes cleaners or cleaning solvents with water to improve cleaning effectiveness.
Choke control: Opens and closes carburetor choke valve.
CU: Cleaning Units. GPM multiplied by psi. (GPM x PSI = CU)
Fuel valve lever: Opens/closes connection between fuel tank and carburetor.
GPM: Gallons Per Minute. The unit of measure for the flow rate of water.
PSI:
kPa (kilopascal):
Quick-connect spray wand: Spray Wand Nozzles.
Thermal relief valve: When the temperature inside the pump rises too high the valve will open and release a gush of water in an effort to lower
the temperature inside the pump. The valve will then close.
Water supply:
gallons per minute.
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