Metrohm 844 UV/VIS Compact IC - Manual (Page 98)

Table of contents
Figure 28: Components of inlet valve 141 and outlet valve 142
4.2.5 Replacing the pump tubing
The pump tubings used by the peristaltic pump are consumable
material with a limited lifetime and should be exchanged at regular
intervals (approx. every 4 weeks under continuous use).
The working life of pump tubing depends to a considerable extent on
the contact pressure. This is why the contact pressure must be
correctly set as described in Section 2.10.2. If the pump is to remain
switched off for a lengthy period of time the tubing cartridges 96 should
be raised completely by loosening the snap-action lever 98 on the right-
hand side (the set contact pressure remains unchanged).
As the pump is always operated on the same side the 6.1826.110
Pump tubings supplied can be used on both sides. To exchange a
pump tubing proceed as follows:
1 Remove old pump tubing
• Press contact pressure lever 97 on the tubing cartridge 96
down as far as it will go.
• Release tubing cartridge 96 from 50 by pressing down snap-
action lever 98 and remove from mounting pin 40.
• Remove old pump tubing 94.
146 Valve housing
147 Sealing ring (black)
148 Sleeve
149 Sapphire sleeve
The bright side must point towards the
sapphire sphere.
150 Sapphire sphere
151 Ceramic holder for sapphire
sphere
The large recess must point in the
direction of the sapphire sphere
152 Seal
The larger opening must point
outwards
146
147
148
149
150
151
152
146
147
148
151
150
149
152
141
Inlet valve
142
Outlet valve