What Does Alarm 12 Indicate?
Alarm 12 typically signals a low suction pressure condition in the refrigerant circuit.
To protect the compressor, the controller may shut down cooling.
Common Causes
- Low refrigerant charge
- Refrigerant leak
- Dirty evaporator coil
- Blocked airflow
- Failed low-pressure switch
Troubleshooting
- Inspect filters and evaporator coil
- Measure refrigerant pressures
- Check for visible oil residue (leak indicator)
- Test low-pressure switch continuity
Correct the root cause before resetting the alarm.
FAQ
Will adding refrigerant fix it?
Only if the system is properly diagnosed and leaks are repaired.