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9.801-509.0 - C • Karcher Operator's Manual
21
PRESSURE
W
ASHER
T
roub
leshooting Guide
TROUBLESHOOTING
PROBLEM
POSSIBLE CAUSE
SOLUTION
WATER
TEMPERATURE
TOO HOT
Incoming water to machine warm or hot
Lower incoming water temperature.
Gas pressure too high
See specifi cations for proper gas pressure.
Detergent line sucking air
Tighten all clamps. Check detergent lines
for holes.
Defective high limit switch
Replace.
Incorrect burner nozzle size
See serial plate.
Insuffi cient water supplied
Check water GPM to machine.
Restricted water fl ow
Check nozzle for obstruction, proper size.
PRESENCE OF
WATER IN OIL
Oil seal worn
Check and replace if necessary.
High humidity in air
Check and change oil twice as often.
WATER
DRIPPING
FROM UNDER
PUMP
Piston packing worn
Check and replace if necessary.
O-Ring plunger retainer worn
Check and replace if necessary.
DETERGENT
NOT
DRAWING
Air leak Tighten all clamps.
Check detergent lines for holes.
Detergent metering valve packing not tight
or packing worn
Tighten nut. Replace valve or packing.
Filter screen on detergent suction hose
plugged
Clean or replace.
Dried up detergent plugging metering valve
Disassemble and clean thoroughly.
High viscosity of detergent
Dilute detergent to specifi cations.
Restriction behind fl oat tank screen
removed
Install restriction.
Hole in detergent line(s)
Repair hole.
Strainer basket plugged
Remove and clean.
Connections on selector valve loose
Put tefl on tape on all pipe connections.
Detergent solenoid not opening
(where applicable)
Check fl ow switch, replace detergent
solenoid.
PUMP
RUNNING
NORMALLY
BUT PRESSURE
LOW ON
INSTALLATION
Pump sucking air
Check water supply and possibility of air.
Valves sticking
Check and clean or replace if necessary.
Unloader valve seat faulty
Check and replace if necessary.
Nozzle incorrectly sized
Check and replace if necessary
(See serial plate for proper size).
Worn piston packing
Check and replace if necessary.
FLUCTUATING
PRESSURE
Valves worn
Check and replace if necessary.
Blockage in valve
Check and replace if necessary.
Pump sucking air
Check water supply and air seepage at
joints in suction line.
Worn piston packing
Check and replace if necessary.
PUMP
NOISY
Air in suction line
Check water supply and connections on
suction line.
Broken or weak inlet or discharge valve
springs
Check and replace if necessary.
Excessive matter in valves
Check and clean if necessary.
Worn bearings
Check and replace if necessary.
Summary of Contents for HDS3.5/20
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