Metrohm 940 Professional IC Vario ONE/SeS/PP/Prep 1 - Manual (Page 86)

5.8 Servicing the high-pressure pump
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940 Professional IC Vario ONE/SeS/PP/Prep 1 (2.940.1510)
￭ Has the pressure dissipated?
￭ Is the instrument switched off?
1 Release the coupling from the pressure screw and seal it with a stop-
per.
2 Unscrew and remove the pressure screw on the pump head's output
(17-8).
3 Unscrew and remove the four fastening screws (17-3) using the hex
key.
4 Remove the pump head (17-4).
Replacing the piston seal
Carry out the following work on both pistons in turn.
Servicing a piston consists of the following tasks:
1. Replace the piston seal.
2. Optional: Clean or replace the zirconium oxide piston.
3. Reinstall the piston.