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17
Troubleshooting and basic settings
Unit does not run
Overflow valve disassembled
Check pressure switch
Pressure switch defective
– Disconnect the unit from the mains and, with
the unit switch on, measure electrical resi-
stance between the connecting terminals (in-
let-outlet). In a pressureless state, there should
be zero Ohms (contacts closed).
– If necessary, replace defective parts and reset
the pressure switch (see page 22).
Overflow valve stuck
– If the overflow valve has switched off the unit
via the pressure switch and is then stuck, the
unit will not start.
– Disassemble the overflow valve and check
whether it moves easily. If necessary, replace
defective parts.
– Lubricate all O-rings with silicone grease
6.288-080.
– Adjustment, see page 22.
L
1
L
2
L
3
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...