Agilent Technologies 5975T LTM GC/MSD, Troubleshooting And Maintenance Manual

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28 Troubleshooting and Maintenance Guide
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Concepts and General Tasks
Troubleshooting Tips and Tricks
Rule 1: “Look for what has been changed.”
Many problems are introduced accidentally by human actions.
Every time any system is disturbed, there is a chance of
introducing a new problem.
• If the MSD was just pumped down after maintenance,
suspect air leaks or incorrect assembly.
• If carrier gas or helium gas purifier were just changed,
suspect leaks or contaminated or incorrect gas.
•
If the LTM column was just replaced, suspect air leaks or
contaminated or bleeding column.
Rule 2: “If complex isn't working, go back to simple.”
A complex task is not only more difficult to perform but also
more difficult to troubleshoot. If you're having trouble detecting
your sample, verify that autotune is successful.
Rule 3: “Divide and conquer.”
This technique is known as “half-split” troubleshooting. If you
can isolate the problem to only part of the system, it is much
easier to locate.
To determine whether an air leak is in the GC or the MSD, you
can vent the MSD, remove the column, and install the blank
interface ferrule. If the leak goes away, it was in the GC.