GC Failure Modes – Visual Root Cause Analysis

Most GC problems present themselves on the chromatogram before any alarm appears. This page links common field symptoms to their most likely causes so technicians can troubleshoot logically and quickly.

Symptom → Cause → Action Map

Follow the arrows from observed symptom to root cause, then apply the recommended corrective action.

Golden Troubleshooting Rules

• Always troubleshoot the sampling system before the GC hardware.
• Valve timing issues appear immediately on the chromatogram.
• Pressure instability causes more errors than electronics.
• Do not recalibrate until the root cause is corrected.

Field Tip

If multiple symptoms appear together, suspect a common upstream cause such as contamination, pressure fluctuation, or air supply failure rather than individual component faults.