![background image](http://html.mh-extra.com/html/karcher/1-509-035/1-509-035_operating-instructions-manual_653779021.webp)
HD 4000 C / HD 6000 C
English
5.956-648 A10369 (06/98)
E. Maintenance
E4
Interval
Procedure
Subject Assembly
Activity
By whom
monthly, or
after 200
operating
hrs.
Check
overflow valve
Overflow valve
Dependent on the number of
high-pressure handguns used, the
pressure reading fluctuates between
the preset value and approx. 15 bar
below the same. On closing all
handguns, the gauge will read
approx. 0 bar. In the event of
malfunction, call customer service.
Operator
Customer
service
Check
low-water
sensor
Float switch in float
reservoir
For about 5 seconds press down the
float of the low water protection
facility and check the fault indication
on the printed circuit board. If
necessary remove any deposits.
Trained
operator
authorised
to open
control
cabinet
Clean
strainers
Dirt trap upstream of float
reservoir,
Pressure controller
Switch OFF unit, turn OFF water,
release pressure. Disassemble and
clean strainers.
Operator
Check float
valve
Float reservoir
Water level must stand 40 mm
below the overflow weir. With float
valve closed, no water may exit. For
adjustment information, refer to the
Service Manual.
Operator
Check
pressure relief
valve
Pressure relief valve on
pump
When functioning correctly, the
motor must reach full RPM within
2 seconds. If required, clean the
strainer upstream of the pressure
release valve. Prior to cleaning:
Shut OFF water, set Emergency-
STOP master switch to OFF.
Operator
Check run-on
interval
System control
Close utiliser (e.g. handgun).
After the after running time (approx.
15 sec) the pump must switch off.
Operator
Check
automatic
switching on
Pressure switch
The pump is stationary as no water
is being drawn. Open the handgun.
When the pressure in the
high-pressure network drops below
25 bar, the pump must switch on.
Operator
Tighten hose
clamps
All hose clamps in/on the
unit
Tighten hose clamps with torque
wrench.
Torque:
28 mm nominal diameter: 2 Nm
29 mm nominal diameter: 6 Nm
Operator