How many air conditioning packs (air cycle machines) are there?
2
What will happen when a temperature selection is made towards cool?
During cooling operations, most of the cool air is directed to the PSU panels and graspers, and some to the lower dado panels. (Opposite for heating).
During standard temperatures it is half/half distribution.
What will happen if an air conditioning pack overheats?
- The related pack shuts down
- related CABIN PACK HOT or FLT COMPT PACK HOT caution light illuminates.
- It will remain on, unless the condition disappears and the related PACKS switch has been set to OFF.
What is the difference between auto and manual mode of the air conditioning system?
Manual:
the ECU’s analog channels control only the pack bypass valves (in response to manual inputs) to regulate cabin or flight compartment temperatures. The FCSOV remains in full open configuration when operating in manual mode.
Auto:
the ECU’s digital channels control the operation of the pack Flow Control and shut off valve (FCSOV) and the respective pack bypass valve (in response to manual inputs) to automatically regulate cabin or flight compartment temperatures.
What is the operational difference between auto and manual mode of the air conditioning system?
AUTO:
(Knob full warm) The cabin/ FLT compartment temp is adjusted to 27C
(Knob full cool) the cabin/FLT compartment temp is adjusted to 15C
MAN:
(Knob full warm) adjusts cabin duct/FLT compartment duct temp to 71C
(Knob full cool) the analog channel supplies control and adjusts cabin duct duct temp to 3C
What will happen if flight compartment or cabin duct supply overheat condition occurs?
The related;
- pack TSOV closes (turbine shut-off valve)
- FLT COMPT DUCT HOT caution light comes on
- CABIN DUCT HOT caution light comes on
- the ECU will adjust the related pack bypass valve toward closed to aid in cooling the duct.
- related light will stay illuminated until the related PACKS switch is set to OFF and the condition or BIT fault goes away.
