Ametek 5000 Instrument Manual page 82

Dryer or Trap Refilling
!
CAUTION
1. Shut off sample and reference gas flows at their sources.
2. Unscrew the two ferrule nuts (32) and disconnect the two lines from the dryer or trap.
3. Unstrap the dryer or trap (33) from its mount.
4. Remove the fill plug (34) and the snubber (35), and empty the contents.
5. Clean the inside thoroughly (do not use water). Be sure it is completely dry.
6. Fill the dryer with new molecular sieve (dried), or fill the trap with new activated charcoal.
7. Install the fill plug and snubber.
8. Do the following to the superactivated dryer:
a. Attach the bottom fitting to a flowmeter with a valve.
b. Carefully place the cylinder in an oven with a source of dry gas < 0.1 ppm (known good su-
peractivated dryer) connected to the top fitting.
!
WARNING
c. Adjust oven heat to 125°C and purge flow to 100 mL/min; allow it to run at temperature for 12
hours.
d. Shut off purge and oven heat, and allow the cylinder to cool for at least 1 hour.
!
CAUTION
e. Disconnect and cap both ends, and remove the cylinder from the oven.
9. Install the unit and connect the lines.
Leak Testing
1. Carefully remove the lid and set it aside.
2. Cap the back pressure exhaust and reference gas inlet tubes.
3. Apply 200 kPa (30 psi) gauge instrument air pressure to the sample inlet.
!
CAUTION
4. Close the SAMPLE gas flow control valve while maintaining the applied pressure in the analyzer.
6-16
5000 Multi Point Moisture Analyzer
If the dryer or trap is to be moved to another area to replace the molecular sieve in
the dryer or the activated charcoal in the trap, place caps over the fittings while
transporting the unit. This will prevent fitting damage.
Make sure that one end fitting is open before applying heat to the cylinder. If the sieve
is moisture laden and the fittings are capped, the cylinder could explode when heated.
Wear gloves. The cylinder will still be hot.
Pressures over 30 psi could destroy the gauge.