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19
Troubleshooting and basic settings
Unit does not reach required pressure
Check seal of valves
Disassemble the pressure valves/suction valves
Vent the unit
Pump not vented
– Switch off the unit. With the gun open, open
the water inlet and wait until the water comes
out without any bubbles.
Pump takes in air
– Check all the seals of the water inlet hose
connection.
Pressure valves leaking
– Unscrew the screw plugs.
– Pull out the valves and check for damage and
dirt. Replace if necessary.
– Mount all O-rings using silicone grease.
– Mount all screw plugs, noting the torque (see
technical data).
Suction valve leaking
– Remove the suction cover.
– Pull out the valves and check for damage and
dirt. Replace if necessary.
– Mount all O-rings using silicone grease.
– Install the suction cover, noting the torque
(see technical data).
Check seal of valves
– Position the valves with the valve seat up-
wards and fill with water. If the valves are
defective, the water will leak out underneath.
Replace valves if necessary.
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Summary of Contents for HD 1090
Page 1: ...HD 1090 Service Handbook 0 I 5 905 212 03 02...
Page 4: ...2 Unit function Equipment 10 15 12 9 10 13 11 14 16 1 8 2 3 4 5 6 7 0 I...
Page 6: ...4 Unit function Functional diagram 5 3 7 8 9 10 11 12 13 14 2 1 15 16 17 4 6...
Page 8: ...6 Unit function Pump 15 17 18 10 12 13 11 14 16 20 9 12 11 1 8 2 3 4 5 6 7 11 19 21...
Page 10: ...8 Unit function Pressure and flow control with the Servopress handgun 1 2 4 3...
Page 14: ...12 Unit function Handgun with pressure and flow control Servopress with low effort version...