Agilent Technologies 7890A Troubleshooting

66 Agilent 7890 Series Troubleshooting
3 Chromatographic Symptoms
3
Confirm that complete inlet maintenance has been
performed. This includes trimming and re-installing the
column.
4 Verify that the injecting device is working properly. If the
method uses a sampling valve, make a direct syringe
injection of concentration similar to that introduced by the
valve. Rule out a problem with the valve.
5 Inspect the mixing liner in the makeup gas adapter. A small
piece of graphite or sample contamination will reduce
sensitivity. See To Replace the uECD Fused Silica Indented
Mixing Liner and Install the Makeup Gas Adapter.
Contamination (high baseline)
If the ECD has a baseline higher than expected for its age, check
the following:
• Rule out all other possible causes. See “Sensitivity” above.
Also check carrier and detector gas supplies, supply gas
traps, and the column.
• Inspect the mixing liner in the makeup gas adapter. A small
piece of graphite can contaminate results. See To Replace the
uECD Fused Silica Indented Mixing Liner and Install the
Makeup Gas Adapter.
• If the detector baseline is > 500 Hz, regardless of detector
age, bakeout the detector. Let it run for 1–2 days.

Agilent Technologies 7890A Specifications

General

Brand	Agilent Technologies
Model	7890A
Category	Laboratory Equipment
Language	English