Kärcher STP-231007D, Manual

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Manual Karcher STP 9.801-191.0 - B
PRESSURE
W
ASHER
Tr
oub
leshooting Guide
28
PROBLEM POSSIBLE CAUSE SOLUTION
LOW OPERATING
PRESSURE
Faulty pressure gauge Install new gauge.
Insufficient water supply Use larger garden hose; clean filter washer at water inlet.
Old, worn or incorrect spray nozzle Match nozzle number to machine and/or replace with new
nozzle.
Plumbing or hose leak Check plumbing system for leaks. Re-tape leaks with teflon
tape.
Faulty or mis-adjusted unloader valve
(where applicable) Adjust unloader for proper pressure. Install repair kit when
needed.
Worn packing in pump Install new packing kit.
Fold or dirty inlet or discharge valves in pump Clean inlet or discharge valves.
Worn inlet or discharge valves Replace with valve kit.
DETERGENT NOT
DRAWING Air leak Tighten all clamps. Check detergent lines for holes.
Valve in the injector head may be blocked, dirty,
or damaged Clean or replace valve in injector.
Filler 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 specifications.
Hole in detergent line(s). Repair hole.
Low detergent level Add detergent if needed.
Discharge water temperature above 180° F Lower discharge water temperature.
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 see page 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.
LOW WATER
TEMPERATURE Improper fuel or water in fuel Drain fuel tank and replace with proper fuel.
Low fuel pressure Increase fuel pressure.
Weak fuel pump Check fuel pump temperature. Replace pump if needed.
Fuel filter partially clogged Replace as needed.
Soot build up on coils Clean coils with soot remover.
Lime build up on coils Clean inside of coils using coil cleaner.
Improper burner nozzle Call technical service for proper size.
WATER
TEMPERATURE
TOO HOT Incoming water to machine warm or hot Lower incoming water temperature.
Fuel pump pressure too high Lower fuel pressure.
Fuel pump defective Replace fuel pump.
Detergent line sucking air Tighten all clamps. Check detergent line for holes.
Defective high limit switch (thermostat) Replace.
Insufficient water supplied Check GPM to machine.
Restricted water flow Check nozzle for obstruction, proper size.
TROUBLESHOOTING