General Maintenance Information; Replacing The Check Valve Cartridges; Outlet Check Valve Cartridge - Varian 212-LC Manual Del Usuario

General Maintenance
Information

Replacing the Check Valve Cartridges

This section covers the replacement and installation of routine
replacement parts which can be performed by the user. These repairs
are typical of many pumps used in Liquid Chromatography and are
described in detail in this section. Please contact your local Varian office
to arrange service calls by our certified field service representatives for
additional services regarding the pumps. To maintain the pump in top
working condition, Varian recommends a preventative maintenance
schedule which includes replacing both check valve cartridges and pump
seals every six months. See page 30 for a complete list of user
serviceable spare parts required for these operations.
Dangerous voltages are exposed when the cover is removed. The
power cord must be disconnected before the cover is removed.
Replacement is recommended every 6 months. The pump inlet and
outlet check valve cartridges are contained in hex nut check valve
housings located on the top (outlet) and bottom (inlet) of the pump head
assembly (Figure 10).

Outlet Check Valve Cartridge

Using the 1/4" open end wrench (provided) loosen the 1/16" crossover
tube nuts and remove the 1/16" crossover tube. Remove the outlet
housing with a 1/2" open end wrench (not provided) and replace the
outlet cartridge making sure the arrow on the cartridge is aligned with the
flow direction. Replace the housing and crossover tube and tighten all
fittings until they are leak free.
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