Simpson 7108644 Use And Care Manual page 24

Terms
● PSI – Stands for pounds per square inch and measures the water pressure or stripping
power produced by the pressure washer. The higher the PSI number, the greater the
pressure and stripping power produced.
● GPM – Stands for gallons per minute and measures the flow rate of the water. The
higher the GPM, the greater the flow or rinsing power produced.
● CU – stands for cleaning units. PSI x GPM = CU. Measures performance efficiency of
the pressure washer. Generally, the higher the CU, the more powerful and efficient the
machine is.
Preparation
● Read all warnings and instructions in this and all other manuals that came with the
pressure washer.
● Remove all toys, bikes, lawn furniture, etc. from the work area if they should not be
sprayed.
● Sweep any loose dirt and debris from the surface you will be pressure washing.
● Cover nearby plants to avoid damaging them with pressure washer spray.
● Lay tarps down to collect paint chips and other debris that get blown off by spray. Exterior
surfaces of houses built before 1977 may produce lead paint chips that will have to be
collected and properly disposed of at a hazardous waste facility.
● Cover or avoid spraying windows as high-pressure spray can break them.
Pressure Washing
● A wider spray equals faster cleaning, while tighter spray equals deeper cleaning.
● Do not aim the nozzle straight at a surface. Hold the wand at a 45-degree angle to the
surface at a distance that cleans well without causing damage.
● Keep the nozzle about 4-feet away from siding to prevent damage to surfaces.
● Start washing siding at the bottom and work your way up, then rinse from the top down.
● Avoid driving water up behind siding.
● Use overlapping strokes for even cleaning.
● Work in smaller areas and do not let soap dry on surfaces.
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OPERATION TIPS