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

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Chromatographic Symptoms
3
Troubleshooting and Maintenance Guide 65
Difficulty with the HED supply
The only time this error occurs is if the output of the supply
cannot get to its destination (the HED).
• Large peak, such as the solvent peak, eluted while the
analyzer was on
• Pressure in the analyzer chamber is too high
• Detector is not working correctly
• MSD electronics are not working correctly
Difficulty with the high vacuum pump
This indicates the pump failed to reach 50% of full speed within
7 minutes or experienced a fault.
You must switch the MSD off and back on to remove this error
message. Be sure the turbo pump has slowed down before
switching off the MSD. The message will reappear if the
underlying problem has not been corrected.
Turbo pump
• Large vacuum leak is preventing the turbo pump from
reaching 50% of full speed
• Foreline pump is not working correctly
• Turbo pump is not working correctly
• Turbo pump controller is not working correctly
• MSD electronics are not working correctly
High foreline pressure
• Excessive carrier gas flow (typically > 5 mL/min)
• Excessive solvent volume injected
• Large vacuum leak
• Severely degraded foreline pump oil (standard foreline
pump)
• Collapsed or kinked foreline hose
• Foreline pump is not working correctly
Internal MS communication fault
• MSD electronics are not working correctly