HD 4000 C / HD 6000 C
English
5.956-648 A10369 (06/98)
F1
F. Trouble Shooting
Problem
Possible Cause
Remedy
by whom
High-pressure
pump fails to
come up to
pressure
Leaking suction-side tubing
system
Check fastener and hose
connections
Operator
Water starvation
Correct the cause
Operator
Defective valve in pump
High-pressure solenoid valve
fails to close
Replace valves
Customer
Service
Pronounced pump
knock, pressure
gauge pointer
oscillates
Defective dashpot
replace
Operator
Pump is drawing air
Check suction line
Operator
Defective valve seat or valve
spring
Replace as required
Customer
Service
With hot-water
accessory kit only
Defective or calcified
precompression pump
Check precompression
pump
Operator
Overflow volume
is blown out into
open, and/or
safety valve is
activated
Blown hose between overflow
valve and float valve
replace
Operator
Defective overflow valve
CAUTION: For safety reasons,
excess water is vented
outdoors.
Shut down the system!!
Repair or exchange
overflow valve
Customer
Service
Water is returning
to float reservoir
despite full-volume
usage
System is calcified
Decalcify system circuits
(refer to Maintenance
section)
Operator
Defective spray lances and/or
nozzles.
Check spray lances
Operator
Defective overflow valve
Check overflow valve
Cust. Service
Overflow valve
cycles ON and
OFF despite zero
usage
Leak in high-pressure system,
defective spray gun.
Repair leak
Operator
Leaking non-return valve or
control piston seal in overflow
valve
Repair overflow valve
Customer
Service
Pump does not
reach working
RPM with and/
or - starter.
Blocked strainer upstream of
solenoid valve
Clean strainer
Operator
Defective pressure relief
solenoid valve
Replace solenoid valve
Customer
Service