Applicable Systems
GA Series Compressed Air System
Symptoms
The compressor failed to reach the minimum working pressure of 7.0 bar (102 psi) within the allowed load time of 60 seconds. The unit continues running but logs a Major alarm.
Possible Causes
- Inlet control valve stuck closed or solenoid not energizing
- Minimum pressure/check valve stuck open causing blow-back to atmosphere
- Excessive air demand exceeding the rated free-air delivery (FAD) of the unit
- Air end wear causing internal leakage and reduced compression efficiency
Troubleshooting Steps
- Step 1: Listen for the inlet valve solenoid click during load/unload toggle via the test menu
If no click, test solenoid coil resistance (expect 20-30 ohm) and supply voltage - Step 2: Isolate the compressor from the plant air network and verify tank pressure rise
If pressure still does not build, inspect the minimum pressure valve for debris or broken spring - Step 3: Check the air end discharge temperature trend - a rise of >15C above baseline suggests internal wear
Schedule an air end rebuild if temperature trend is abnormal and pressure delivery is low
How to Reset
Reset: Press Alarm Reset after the root cause is corrected. The alarm clears once the compressor successfully loads and reaches setpoint pressure within the configured time.
Common Replacement Parts
- 1613-7830-00: Inlet valve assembly, GA 30+ (Includes solenoid, piston, and guide)
- 1613-9000-00: Minimum pressure valve kit (Replace spring and poppet seat if worn)
Frequently Asked Questions
- Q: What is normal load time for a GA 45?
A healthy GA 45 should reach 7.5 bar from 0 bar in 25-40 seconds when unloaded and isolated. Times over 60 seconds indicate a problem.
- Q: Does this alarm mean the air end is worn out?
Not necessarily. Check the inlet valve and minimum pressure valve first. Only suspect air end wear if all valves test good and discharge temperature is elevated.
Source: Atlas Copco GA 30-90 Service Manual, 2950 1630 00
Category: Compressor