DeVillbiss Air Power Company 2225CWH Operation, Pressure Washer Terminology, Bypass Mode

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OPERATION

PRESSURE WASHER TERMINOLOGY

PSI: Pounds per Square Inch. The unit of measure for water pressure. Also used for air pressure, hydraulic pressure, etc.

GPM: Gallons Per Minute. The unit of measure for the flow rate of water through the pressure washer.

CU: Cleaning Units. GPM multiplied by PSI.

Bypass Mode: In Bypass Mode, the pump is recircu- lating water because the trigger of the spray gun is not pulled.

Chemical Injection: Feeds cleaning agents into the pump to mix with the pressurized water and help in cleaning.

Water Supply: All pressure washers must have a source of water. The minimum requirements for a water supply are 20 PSI and 5 gallons per minute.

NOTE: Any supply pressure or delivery rate less than this will not allow the pressure washer to operate at its full potential.

OPERATING FEATURES OF YOUR PRESSURE WASHER

BYPASS MODE

During normal operation water supply is turned on, engine is running, spray gun trigger is depressed, and the cold water supply circulates inside the pressure washer pump allowing pump to maintain a safe operating temperature. When you release spray gun trigger and engine is still running, you are in bypass mode.

When unit is in bypass mode, water circulating inside the pump begins to heat up. If unit is left in bypass mode for more than two (2) minutes, the water tem- perature will rise to a dangerous level and damage internal components of the pump.

If pressure washer is operated without an adequate water supply or operated for more than two (2) min- utes without depressing the spray gun trigger, the pump will overheat and be seriously damaged. Any damage to pump due to these causes will not be covered under warranty.

THERMAL RELIEF VALVE

In an effort to prevent damage, pumps are equipped with a thermal relief valve. This valve will open when the temperature inside the pump rises too high. This valve will then release a gush of water in an effort to lower the temperature inside the pump. Immediately after this occurs, the valve will close.

DO NOT allow your unit to operate in bypass mode for more than two minutes at any time. Overheating of pump will cause damage to pump.

PRESSURE ADJUSTMENT

The pressure output of the DAPC pump on your pressure washer is preset at the factory to achieve optimum pressure and cleaning. It is not adjustable. If you need to lower the pressure, there are two meth- ods.

The first method is to back away from the surface being cleaned. The farther away you are, the less pressure is delivered to the surface being cleaned.

The second method is to reduce the speed of the gasoline engine (RPM). Slow the engine down and the water pressure will go down with it.

DO NOT attempt to increase pump pres- sure. A higher pressure setting than the factory set pressure will damage pump.

9 — ENG

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Contents Pressure Washer Safety Guidelines Definitions Table of ContentsOwners Responsibilities Pressure Washer Return PolicyONE Year from Date of Purchase WarrantyHazard What can Happen HOW to Prevent IT Important Safety InstructionsHazard What can Happen HOW to Prevent IT Contents of Carton Unpacking AssemblyPressure Washer Basics Basic Elements of a Pressure WasherBasic Elements of Engine Pressure Adjustment Bypass ModeOperation Pressure Washer TerminologyHOW to Siphon CHEMICALS/CLEANING Solvents HOW to USE WandBefore Starting Typical HOOK-UP PRE-START ChecklistShutting Down Your Pressure Washer Maintenance HOW to Clean the NozzlePump HOW to Clean the Water Inlet Filter StoragePreparation for Storage Problem Cause Correction TroubleshootingRepair Parts ENG ENG Quick Facts Pressure Washer Quick Facts