Teledyne 4700 Serivce Manual page 20

4700 Refrigerated Sampler Service Guide
Section 1 Introduction and General Guidelines
1-8
2. Loosen the Liquid Detector Cover (G) by unscrewing the
large black knob (I).
3. Unlatch the Pump Housing Band (K).
4. Pull the tube (A) away from the bulkhead fitting (B) and
disconnect the tubing coupler and suction line. (Cutting
the pump tubing may be necessary.)
5. Pull the old pump tube through the pump.
6. Thread the new pump tube through the pump. Note that
the short end (inlet) should extend from the top opening.
7. Align the blue collars with the alignment notches.
8. Close the liquid detector cover and secure it tightly with
the large knob.
9. Close the pump housing band and secure it with the latch.
10. Reset the pump-tube counter. (See the "Resetting the Pump
Tube Alarm" example.)
11. Take a "dry" grab sample (section 4.4) to test the new tube.
12. Reconnect the suction line.
Pump Tube Life – Several factors shorten the pump tube life,
including:
• Incorrect installation
• Abrasive materials suspended in sample liquid
• Frequent line rinses
• Long purge cycles, such as those used with long suction
lines
To extend the life of the pump tube:
• Always use Isco pump tubes.
• Install the tube properly, aligning the blue collars
correctly in the notches.
• Follow the natural curve of the tube when routing the
tube around the pump rollers.
• Minimize the line rinses and sampling retries in the
sampling programs.
• Use the shortest possible suction line.