Aviation Mechanic - General, Airframe, and Powerplant › II. Airframe › Task G. Environmental Systems

AM.II.G.K6

Knowledge

Vapor-cycle system and system component(s) operation, servicing, and inspection procedures.

Study note

Get a short, cited explanation of this element written from the FAA handbooks: the core idea, the numbers that matter, common test traps, and a quick self-check.

From the FAA library

Aviation Maintenance Technician Handbook - Airframe p. 16-56
Chapter 16: Cabin Environmental Control Systems › Vapor Cycle Air Conditioning › System Servicing
Water is removed from the system by evacuation. Anytime the system refrigerant charge falls below atmospheric pressure, the refrigerant is lost, or the system is opened, it must be evacuated before recharging. Evacuating a vapor cycle air conditioning system ... also known as pumping down the system. A vacuum pump is connected and pressure inside the system is reduced to vaporize any water that may exist. Continued operation of the vacuum pump draws the water vapor from the system…
Aviation Maintenance Technician Handbook - Airframe p. 16-44
Chapter 16: Cabin Environmental Control Systems › Vapor Cycle Air Conditioning › Vapor Cycle Air Conditioning System Components
Vapor Cycle Air Conditioning System Components By examining each component in the vapor cycle air conditioning system, greater insight into its function can be gained. Refrigerant For many years, dichlorodifluoromethane (R12) was the standard refrigerant used in aircraft vapor cycle ... conditioning systems. Some of these systems remain in use today. R12 was found to have a negative effect on the environment; in particular, it degraded the earth’s protective ozone layer. In most cases, it has been replaced by tetrafluoroethane…