Metrohm 942 Extension Module Vario Manual page 41

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Recommended pro-
cedure
Accessories
942 Extension Module Vario ONE/Deg (2.942.1060)
Unstable baseline (pulsations, flow fluctuations)
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CAUTION
Maintenance work on the high-pressure pump may not be carried out
unless the instrument is switched off.
We recommend the following procedure for the maintenance of the
pump head:
1. Service the inlet valve and the outlet valve.
2. Remove the pump head.
3. Service both pistons, one after the other.
a. Remove piston.
b. Dismantle the piston.
c. Replace the piston seal.
d. Replace the zirconium oxide piston.
e. Assemble the piston.
f. Insert the piston.
4. Reinstall the pump head.
You can find brief video sequences on the following maintenance steps on
the Internet at http://ic-help.metrohm.com/.
Servicing the outlet valve and inlet valve
For this step, you need the following accessories:
Adjustable wrench (6.2621.000)
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5 Operation and maintenance
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