Decision Tree: Sampling / Conditioning
Goal: clean, dry, stable sample.
Most Wobbe errors originate from sample conditioning.
1) Check filters and coalescers. Replace if contaminated or blocked.
2) Verify drains: no liquid accumulation; drains functioning correctly.
3) Check moisture/dewpoint issues; confirm heat tracing (if applicable).
4) Inspect for liquid carryover during process upsets (major spike cause).
5) After correction: confirm trend stability, then compare to reference.
Major Troubleshooting
- Spikes / jumps: liquid carryover, blocked drains, sudden composition change.
- Slow drift: moisture ingress, contamination, saturated filters.
- Calibration fails: unstable sample or incorrect calibration gas flow.