If Pack No. 1 fails, the following occurs:

• Pack flow control valve No. 2 will move to a higher flow position, regardless of the PACK FLOW Selector setting.
• Pack flow control valve No. 1 will fail.
• The Hot Air Pressure Regulating Valve will close.
• Basic temperature regulation will be maintained, but optimization is lost, with Pack No. 2 solely controlling the temperature.
• The Cockpit Trim Air Valve will close.
• Both cockpit and cabin temperatures will be maintained at fixed values.
• Due to the closure of the Hot Air Pressure Regulating Valve, all trim air valves will close.