Agilent Technologies 7890A Troubleshooting Manual page 20

2
ALS and Detector Symptoms
FID Ignitor Does Not Glow During Ignition Sequence
WA R N I N G
20
Keep body parts at a safe distance from the FID chimney while
performing this task. If using hydrogen, the FID flame will not be
visible.
1 Remove the detector top cover.
Turn the FID flame On.
2
3 Observe the ignitor plug though the FID chimney. The
small hole should glow during ignition sequence.
If the test fails, check for the following possible causes:
• The ignitor may be bad; replace the ignitor.
• Detector temperature is set to < 150 °C. Agilent
recommends operating the FID at > 300 °C.
• The ignitor is not making a good connection to the
ground:
• The ignitor must be tightly screwed into the FID castle
assembly.
• The three T- 20 Torx screws that hold the collector
assembly in place must be tight.
• The brass knurled nut that holds the FID castle
assembly in place must be tight.
Perform FID maintenance if these parts are corroded or
oxidized.
T-20 Torx screws (3)
Ignitor
Knurled nut
Troubleshooting