46 Troubleshooting
3 Chromatographic Symptoms
NPD Response Low
• Perform complete inlet maintenance: Replace all consumable
parts and bake out the inlet.
• Perform column maintenance: Bake out contaminants as
needed. Verify correct column installation
• A large concentration of solvent has extinguished the
hydrogen/air plasma. Increase the bead voltage.
• Measure the actual gas flow at the detector. (See “To Measure
a Detector Flow” .)
• Check for a partially plugged jet.
• Verify that the bead is activated. Look through the vent hole
on the detector lid to see if the bead is glowing orange.
Replace the insulators/collector.