Air Compressor Fault Codes — How to Use This Guide
Air compressor fault codes vary by brand, but the root causes are usually familiar: high discharge temperature, low oil pressure, motor overload, sensor failure, or drive faults. This page is a hub designed to help technicians narrow the problem before diving into the model-specific manual.
Common Air Compressor Fault Categories
| Fault Type | Typical Meaning |
|---|---|
| High discharge temperature | Cooling issue, low oil, dirty cooler |
| Low oil pressure | Oil pump issue, low oil, pressure switch fault |
| Motor overload | High mechanical load, voltage issue, starter/VFD problem |
| Sensor fault | Pressure, temperature, or transducer out of range |
| Emergency stop / safety trip | E-stop chain, high pressure, separator issue |
| VFD fault | Overcurrent, undervoltage, overtemperature |
Common Causes Across Brands
- High temperature — Dirty aftercooler, blocked inlet filter, failed cooling fan, or low oil.
- Low pressure / low output — Air leak, inlet valve failure, worn airend, or wrong pressure setpoint.
- Motor overload — Tight airend, bad bearings, unbalanced voltage, or blocked separator.
- Frequent shutdowns — Short cycling due to poor pressure band settings or undersized storage.
Step-by-Step Fix {#fix}
- Read the exact code and subsystem — Controller display plus any starter or VFD alarms.
- Check basics first — Oil level, inlet filter, coolers, ventilation, and supply voltage.
- Verify load/unload behavior — Make sure the compressor is not hunting between states.
- Inspect sensors and transducers — Many modern compressor faults are bad feedback, not true mechanical failure.
- Review trend data if available — Controller history often shows temperature rise or pressure drift before shutdown.
Brands Covered on ErrorCodeFixes
- Atlas Copco
- Ingersoll Rand
- Kaeser
- Sullair
- Gardner Denver
- Boge
- CompAir
- FS-Elliott
When to Call a Pro
If the compressor shows repeated airend, oil pressure, or drive faults, stop resetting it and bring in a compressed air technician. Running a screw compressor through repeated trips can turn a manageable repair into a full airend failure.