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Manual Karcher STP 9.801-191.0 - B
9
PRESSURE W
ASHER
OPERA
TOR’S MANU
AL
PREVENTATIVE MAINTENANCE AND SERVICE
PREVENTATIVE MAINTENANCE
1. Use clean fuel - kerosene, No. 1 home hearing
fuel or diesel fuel. Clean or replace fuel filter every
100 hours of operation. Avoid water contaminated
fuel as it will seize up the fuel pump. De-soot coils
monthly. Use an additive if diesel is being used.
2. Check to see that the attached pressure washer
water pump is properly lubricated.
3. Follow Winterizing Procedures to prevent freeze
damage to pump coils.
4. Always neutralize and flush detergent from system
after use.
5. If water is known to be high in mineral content, use
a water softener in your water system or de-scale
as needed.
6. Do not allow acidic, caustic or abrasive fluids to be
pumped through system.
7. Always use high grade quality cleaning products.
8. Never run pump dry for extended periods of time.
9. If machine is operated with smoking or eye burning
exhaust, coils will soot up, not letting water reach
maximum operating temperature. (See section on
Air Adjustments.)
10. Never allow water to be sprayed on or near engine
or burner assembly or any electrical component.
11. Periodically delime coils per instructions.
It is advisable, periodically, to visually inspect the
burner. Check air inlet to make sure it is not clogged
or blocked. Wipe off any oil spills and keep this equip-
ment clean and dry.
The areas around the pressure washer should be kept
clean and free of combustible materials, gasoline and
other flammable vapors and liquids.
The flow of combustion and ventilating air to the burner
must not be blocked or obstructed in any manner.
MAINTENANCE AND SERVICE
Unloader Valves:
Unloader valves are preset and tested at the factory
before shipping. Occasional adjustment of the unloader
may be necessary to maintain correct pressure. Call
your local dealer for assistance.
Winterizing Procedure:
Damage due to freezing is not covered by warranty.
Adhere to the following cold weather procedures
whenever washer must be stored or operated outdoors
under freezing conditions. During winter months, when
temperatures drop below 32°F, protecting your ma-
chine against freezing is necessary. Store machine in
a heated room. If this is not possible then mix a 50/50
solution of anti-freeze/water into a 5 gallon bucket.
Place a short section of garden hose into bucket and
connect it to machine. Elevate bucket and turn pump on
to siphon anti-freeze through machine. If compressed
air is available, an air fitting can be screwed into the inlet
connector and, by injecting compressed air, all water will
be blown out of system.
High Limit Hot Water Thermostat:
For safety, each machine is equipped with a high limit
control switch. In the event that the temperature of the
water should exceed its operating temperature, the high
limit control will turn the burner off until the water cools.
Pumps:
Use only SAE 30W non-detergent oil. Change oil after
the first 50 hours of use. Thereafter, change the oil
every three months or at 500 hour intervals. Oil level
should be checked by using the dipstick found on top
of the pump or the red dot visible through the oil gauge
window. Oil should be maintained at that level.
Cleaning of Coils:
In alkaline water areas, lime deposits can accumulate
rapidly inside the coil pipes. This growth is increased by
the extreme heat build up in the coil. The best preven-
tion for liming conditions is to use high quality cleaning
detergents. In areas where alkaline water is an extreme
problem, periodic use of Deliming Powder (part #9.804-
059.0) will remove lime and other deposits before coil
becomes plugged. (See Deliming Instructions for use
of Deliming Powder.)
Deliming Coils:
Periodic flushing of coils is recommended.
1. Fill a container or optional float tank with 4 gallons
of water, then add 1 lb. of deliming powder. Mix
thoroughly.
2. Remove wand assembly from spray gun and put
spray gun into container. Secure the trigger on the
spray gun into the open position.
3. Attach a short section (3-5 ft.) of garden hose to
machine to siphon solution from an elevated con-
tainer. Turn pump switch on, allowing solution to
be pumped through coils back into the container.
Solution should be allowed to circulate 2-4 hours.
4. After circulating solution flush entire system with
fresh water. Reinstall wand assembly to spray gun.
Removal of Soot in Heating Coil:
In the heating process, fuel residue in the form of soot
deposits may develop between the heating coil pipe
and block air flow which will affect burner combustion.
When soot has been detected on visual observation,
Athe soot on the coil must be washed off after coil has
been removed using the following steps: