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GP-SERIES Operator’s Manual
WATER SUPPLY:
. Select a water supply hose which is a quality grade of garden hose measuring
at least 3/4” ID and no longer than 50 feet.
2 Check the water inlet strainer to ensure it is clean and free of any obstructions.
As a strainer becomes obstructed, it restricts proper flow of water to the
pump. This can result in cavitations which will cause premature failure of
pump packings.
a. Using a screw driver, remove the screen from the water inlet.
b. Clean or replace with Mi-T-M #9-000 if necessary.
3. Connect the hoses.
a. Connect one end of the water supply hose to the water inlet of the
unit.
b. Connect the other end of the hose to your pressurized water supply.
NOTE 1:
Do not use a non-pressurized water supply (i.e. from a pond or well)
with this unit.
NOTE 2:
When connecting the water inlet to the water supply mains, local
regulations of your water company must be observed. In some
areas, the unit must not be connected directly to the public drinking
water supply. This is to ensure there is no feedback of detergents
into the water supply. (Direct connection is permitted if a backflow
preventer is installed. Check with local authorities for approval.)
c. Connect the high pressure discharge hose to the water outlet of the
unit.
d. Securely connect the other end of the hose to the gun assembly. (A
wrench may be required on some models.)
e. Connect the wand assembly to the gun/hose assembly.
4. Follow the incoming water requirements listed below:
a. Water pressure must be a minimum of 25 pounds per square inch (PSI)
and a maximum of 25 PSI. (A typical outdoor faucet will
generally supply this PSI if turned completely “ON”.)
b. Incoming GPM must be approximately one gallon more than the
outgoing GPM stated on the pressure washer nameplate. (You can
check GPM by timing how long it takes to fill a 5 gallon container.)
c. Incoming water temperature must not exceed 25°F. Excessive pump
damage may result if the water temperature exceeds this acceptable
level.
5. Never allow the unit to operate without the incoming water line attached and
the water supply completely turned on.
WATER INLET STRAINER
INSTALLATION & PREPARATION
UNLOADER:
The unloader is equipped with an adjustment knob to adjust the pressure. Should
less pressure be required, simply turn the adjustment knob counterclockwise.
To set back to maximum, turn adjustment knob completely clockwise. DO NOT
OVERTIGHTEN!
THERMAL RELIEF VALVE:
To ensure the water temperature does not exceed acceptable levels, never allow
the pressure washer to operate in the bypass mode (with the unit running and
the trigger gun closed) for more than three minutes.
A “Thermal Relief Valve” has been added to this unit to protect the pump. It
may begin to open and release water if the water temperature in the pump has
exceeded 40°F. This will allow fresh, cool water to enter the system.
CAUTION
RISK OF UNIT DAMAGE!
DO NOT OVERTIGHTEN THE
UNLOADER. bREAKAGE COULD
RESULT IN IMMEDIATE LOSS OF
WATER PRESSURE AND COSTLY
REPAIRS.
