Metrohm 872 Extension Module IC Pump - Manual (Page 50)

6.4 High pressure pump
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42 ￭￭￭￭￭￭￭￭
872 Extension Module IC Pump
piston is on the left (viewed from the front), and the auxiliary piston
is on the right.
Cleaning/replacing the zirconium oxide piston
Clean one piston after the other as follows:
1 Removing the piston cartridge from the pump head
Loosen the piston cartridge with a wrench and unscrew from the
pump head by hand.
2
1
Figure 25 Removing piston
1 Pump head 2 Piston
2 Dismantle the piston
Caution
On the inside of the piston cartridge there is a taut spring than can
jump out of the piston cartridge if suddenly loosing tension.
When opening the piston cartridge, hold pressure towards the
spring and unscrew carefully.
￭ Loosen the screw of the piston cartridge with a wrench and
unscrew carefully by hand and by holding pressure towards the
taut spring.
￭ Remove the zirconium oxide piston and lay on a tissue.