Kärcher HDS 3.9/20 Ea Cage Operator's Manual page 14

PROBLEM
LOW WATER
TEMPERATURE
WATER
TEMPERATURE
TOO HOT
14
TROUBLESHOOTING
POSSIBLE CAUSE
Improper fuel or water in fuel
Low fuel pressure
Weak fuel pump
Fuel filter partially clogged
Soot build up on coils
Lime build up on coils
Improper burner nozzle
Incoming water to machine
warm or hot
Fuel pump pressure too high
Fuel pump defective
Detergent line sucking air
Defective high limit switch
(thermostat)
Incorrect fuel nozzle size
Insufficient water supplied
Restricted water flow
HDS 505, 508, 509, 510 • 9.800-078.0 • Rev. 4/13
SOLUTION
Drain fuel tank and replace with proper fuel.
Increase fuel pressure.
C h e ck f u e l p u m p t e m p e ra t u r e. R e p l a c e
pump if needed.
Replace as needed.
Clean coils with soot remover.
Clean inside of coils using coil cleaner.
See Burner Specifications.
Lower incoming water temperature.
Lower fuel pressure.
Replace fuel pump.
Tighten all clamps. Check detergent line for holes.
Replace.
See Burner Specifications.
Check GPM to machine.
Check nozzle for obstruction, proper size.