Atlas Copco GA Series Faults: What They Mean and How to Fix Them

Atlas Copco GA Series Faults: What They Mean and How to Fix Them

The Atlas Copco GA Series is a workhorse in industrial plants, but controller messages can be confusing when a trip stops production. Use this guide to interpret common GA faults, run safe first checks, and decide when to bring in a technician.

Applies To

• GA fixed-speed rotary screw compressors
• GA VSD variants that include a variable speed drive
• Elektronikon controller generations commonly used on GA units

Before You Start

• Lock out and tag out power before opening panels.
• Write down the exact fault text or code and what the machine was doing when it occurred.
• Do not clear service timers unless the maintenance has been done.

Quick Orientation: Fixed-Speed vs VSD

• GA fixed-speed: Trips often relate to temperature, pressure feedback, interlocks, or mechanical load.
• GA VSD: Adds drive health, overcurrent, and communication items in addition to the above.

Most Common GA Series Controller Messages

1) Drive Not Healthy (A017 or similar) [VSD]

• Meaning: The VSD reports a fault or will not come ready.
• First checks: Clean power cycle, inspect VSD keypad LEDs, reseat interface connectors between controller and drive, verify cooling fans run, confirm ambient is within spec.
• If it persists: Check incoming power quality, look for parameter mismatches after board or drive swaps, review drive trip history.

2) Motor or Inverter Overtemperature (F011, F006) [All, more common on VSD]

• Meaning: Temperature threshold exceeded at the motor or inside the drive.
• First checks: Clean coolers and filters, verify fan rotation and operation, remove dust from heat sinks, check cabinet ventilation and ambient temperature.
• Also check: Loose thermistor wiring and damaged temperature sensors.

3) Overcurrent or Overvoltage (F020, F023) [VSD]

• Overcurrent checks: Spin the airend by hand with power isolated if accessible, inspect belts/couplings, verify inlet valve is not jammed, check for downstream restriction causing load spikes.
• Overvoltage checks: Measure supply voltage at mains, confirm utility stability, verify braking resistor circuit on VSD models.

4) Communication or Converter Timeout [VSD]

• Meaning: Lost comms between Elektronikon and the drive.
• First checks: Reseat low-voltage comm cables, inspect for abrasion or corrosion, confirm service switch position, perform a clean power-down and restart so both devices boot together.

5) Parameter Fail or Format Fail

• Meaning: Parameter mismatch or corruption detected.
• First checks: Confirm correct service or run position. If a component was replaced, reload the proper parameter set from a known good backup. Do not guess values.

6) Run Enable Open or Interlock Open

• Meaning: A permissive is missing, so the machine will not run.
• First checks: Verify emergency stop is released, door switches are closed, external run command is present, and all safety circuits are intact. Trace the circuit through the I/O.

7) High Air/Oil Temperature or High Discharge Temperature

• First checks: Clean coolers, verify cooling fan operation and airflow direction, check ambient and ensure ventilation grills are not blocked.
• Also consider: Low coolant level, wrong lubricant, or fouled thermostatic valve affecting oil flow.

8) Pressure Transducer Fault or Unstable Pressure Reading

• First checks: Inspect the transducer wiring and connector, look for oil contamination in the sensing line, verify system is not rapidly loading and unloading due to downstream swings.
• If readings drift: Compare with a known good gauge to rule out a sensor issue.

9) Separator Differential Pressure High

• Meaning: Excess restriction across the air/oil separator element.
• First checks: Inspect for collapsed or saturated separator, verify correct element fitment, check for blocked return line or scavenge issues, confirm inlet filter restriction is not forcing excessive load.

10) Maintenance Due or Service Required

• Meaning: Scheduled maintenance interval reached.
• Action: Perform the service, then clear the timer. Do not clear as a workaround for a fault.

Fast Checks That Solve Many GA Trips

• Verify incoming voltage and phase quality at the main terminals.
• Inspect and reseat low-voltage connectors on the controller, I/O, and drive.
• Clean coolers and confirm all fans operate and spin in the correct direction.
• Check inlet filter restriction and separator differential pressure.
• Confirm interlocks and external run enable are satisfied.

Recommended Preventative Maintenance Parts

• Air filter replacements to protect the airend and reduce load.
• Oil filter replacements to keep oil clean and protect bearings.
• Air/oil separator replacements to maintain proper differential pressure and oil return.
• Compressor oil replacements matched to your GA model and ambient.

When To Call a Technician

• Repeated overcurrent, overvoltage, or drive not healthy faults after basics are addressed.
• Evidence of parameter corruption without a verified backup file.
• Board damage, arcing, or burnt smell inside the cabinet.

Related Reading

• Atlas Copco Controller Fault Codes: Quick Troubleshooting Guide
• Atlas Copco Elektronikon Fault Code List
• How to Reset Atlas Copco Controller Faults the Right Way
• Why Is My Air Compressor Not Building Pressure
• Why Won’t My Compressor Start
• Compressor Turns On But Doesn’t Load