Figure 2-2. Fluid Schematic

TM 5-4130-234-13&P

Figure 2-2. Fluid Schematic

b. Filling the Service Unit Reservoir: The service unit

the reservoir is full, all valves are closed, hoses

fluid system is first vented to atmosphere to relieve any

disconnected, and fittings capped.

pressure buildup from any refrigerant left in the fluid

c. Leakage Checking Refrigeration System: The

system. The fluid system is then evacuated to check for

refrigeration system is first pressurized to approximately 15

leakage. A bottle of refrigerant is connected to the FILL

psig with nitrogen. The refrigeration system charge valve

connection, the valve on the refrigerant bottle is opened,

is connected to the service unit LOW PRESS gage and the

the FILL valve is opened, and the VENT/EVAC valve is

refrigeration system charge valve is opened. The pressure

carefully controlled to allow the reservoir to fill by venting

indicated on the low pressure gage is monitored for rapid

the pressure buildup in the reservoir to atmosphere. When

decay. If pressure decays rapidly, the leak detector,

furnished with the

2-3