21 Air Conditioning
- 21-09 ECAM Alerts
- 21-21 Air Distribution and Recirculation
- 21-23 Lavatory and Galley Ventilation
- 21-26 Avionics Equipment Ventilation
- 21-28 Cargo Compartment Ventilation
- 21-31 Pressure Control and Monitoring
- 21-43 Cargo Compartment Heating
- 21-51 Pack Flow Control
- 21-52 Air Cooling System
- 21-61 Pack Temperature Control
- 21-63 Cockpit and Cabin Temperature Control