Metrohm 930 Compact IC Flex ChS/Deg Manual page 66

5.7 Servicing the high-pressure pump
5 Inlet valve holder
7 Eluent aspiration tubing connector
Consists of a coupling with a pressure screw.
Maintenance interval
Recommended pro-
cedure
Accessories
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58
The following parts of the high-pressure pump must be serviced at least
once per year:
Inlet valve (6.2824.170)
￭
Outlet valve (6.2824.160)
￭
Piston seal (6.2741.020)
￭
Zirconium oxide piston (6.2824.070)
￭
Maintenance tasks can also be carried out if the following problems occur:
Unstable baseline (pulsations, flow fluctuations)
￭
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:
You can find these parts in the accessory kit: Vario/Flex Basic
(6.5000.000).
Adjustable wrench (6.2621.000)
￭
6 Pressure screw, short (6.2744.070)
Fastened to the inlet valve holder.
8 Pressure screw, short (6.2744.070)
Fastened to the pump output.
930 Compact IC Flex ChS/Deg (2.930.1260)
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