A well-maintained 5-gas analyzer provides reliable measurements that you can trust. Neglecting calibration and filter changes leads to drift, false readings, and misdiagnoses.
Daily Checks
- Warm-up time: Allow the analyzer to warm for at least 10-15 minutes (manufacturer spec) before use.
- Zero calibration: Perform a zero check with fresh air or span gas before each day's use.
- Leak check: Ensure probe and hoses are intact; any leaks cause dilution and low readings.
- Sample filter: Inspect for moisture or oil. Replace if saturated.
Regular Calibration
Use certified span gases to verify accuracy:
- CO span (e.g., 5%)
- CO₂ span (e.g., 16%)
- C3H8 (propane) for HC
- O₂ span (usually fresh air ~20.9%)
- NOx span (if applicable)
Many analyzers have auto-calibration features; still verify monthly with manual spans.
Filter and Probe Maintenance
- Particulate filter: Replace every 3-6 months depending on usage environment.
- Water trap: Empty daily; clean regularly.
- Probe: Clean with appropriate solvent; check O-rings; ensure no blockages.
- Hoses: Replace any that are cracked or contaminated with oil.
Storage
When not in use, store the analyzer in a clean, dry environment. Some units require a desiccant pack in the case. Avoid extreme temperatures and humidity.
Record Keeping
Maintain a log of calibration dates, filter changes, and any repairs. This helps maintain compliance with ISO standards (if applicable) and ensures traceability.
When to Send for Service
If calibration fails repeatedly, or if you suspect sensor drift that you cannot correct, contact the manufacturer for service. Sensors have limited lifespans (typically 1-2 years for heated wideband sensors).
A properly maintained analyzer not only gives accurate results but also saves time and prevents misdiagnosis that could lead to unnecessary part replacements.