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5.4
Check Valve Cleaning and Replacement
Many check valve problems are the result of small particles
interfering with the operation of the check valve. As a result, most
problems can be solved by pumping a strong solution of liquid,
laboratory grade detergent through the check valves at a rate of
1 mL/min for one hour. After washing with detergent, pump distilled
water through the pump for fifteen minutes. Always direct the output
directly to a waste beaker during cleaning. If this does not work, the
check valve should be replaced.
CAUTION: When removing the check valves, keep them in
the orientation shown below the entire time they are not
installed in the pump head. The assemblies may fall apart,
parts may be lost, and they may not operate properly when
re-assembled.
5.5
Pulse Damper Replacement
5.5.1 Removing the Pulse Damper
WARNING:
There are potentially lethal voltages inside the
pump case. Disconnect the line cord before removing the
cover. Never bypass the power grounds.
1. Make certain that the system has been depressurized. Unplug the power
cord and remove the cover.
2. Disconnect the tubing from the pulse damper.
3. Disconnect the transducer from the circuit board.
4. Remove the four screws that secure the pulse damper from the underside
of the pump.
5. Remove the pulse damper.
5.5.2 Pulse Damper Refurbishing
Refurbishing the pulse damper is a time-consuming
procedure. You may want to return the pulse damper to have it
