Operation; Pressure Washer Terminology - Simpson ALH3228 Instruction Manual

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.
CU: Cleaning Units. GPM multiplied by PSI equals CU.
Bypass Mode: Allows water to re-circulate within the pump when the gun trigger is
not pulled. This feature allows the operator to release the trigger gun and reposition
themselves without having to turn the engine off in between cleaning actions.
NOTICE: Allowing the unit to run for more than two minutes without the gun trigger
being pulled could cause overheating and damage to the pump. Do not let the
pressure washer run for more than two minutes in Bypass Mode. Turn off the engine
and relieve the pressure in the gun during these extended situations.
Thermal Relief Valve (Q, fig. 5): When the temperature inside the
pump rises too high, this valve will open and release a gush of
water in an effort to lower the temperature inside the pump. The
valve will then close.
Detergent Injection System: Mixes cleaners or cleaning solvents
with the water to improve cleaning effectiveness.
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.
If your water source is a well, the garden hose length can only be 30 ft. (9 m) max.
WARNING: To reduce the possibility of contamination always protect
against backflow when connected to a potable water system.
pRESSURE WASHER OpERATING FEATURES
pRESSURE ADJUSTMENTS
The pressure setting is preset at the factory to achieve op ti mum pres sure and
cleaning. If you need to lower the pres sure, it can be accomplished by these meth-
ods.
1. Back away from the sur face to be cleaned. The further away you are, the
less the pressure will be on the surface to be cleaned.
2. Change to the 40˚ nozzle (white). This nozzle delivers a less powerful stream
of water and a wider spray pattern. Refer to how To Use Spray Wand.
NOTICE: DO NOT attempt to increase pump pressure. A higher pressure setting
than the factory set pressure may damage pump.
HOW TO USE SpRAY WAND
The nozzles for the spray wand are stored in the nozzle holder on the panel assembly.
Colors on the panel identify nozzle spray pattern. Refer to the following chart to
choose the correct nozzle for the job to be performed.

OpERATION

12- ENG
5
Q