TM 5-4130-234-13&P
To charge a refrigeration system with refrigerant, the
service unit, is connected to the service unit 115 OUTPUT
service unit CHARGE fitting is loosely connected to the
connection, and leaks are isolated, using the leak detector.
refrigeration system receiver valve with a charge hose, and
d. Evacuation of a Refrigeration System: The
the charge hose is purged with refrigerant and tightened on
refrigeration system suction and receiver valves are
the receiver valve connection. The other fittings in the
opened and the system is purged with dry nitrogen to
fluid system of the service unit are capped and the valves
remove any contaminants. Vacuum hoses are attached to
in the fluid system are closed during this operation. After
the suction and receiver valves and to the EVAC fittings on
connecting the hose between the service unit CHARGE
the service unit. The system is then evacuated to 200
fitting and the refrigeration system receiver valve, the
microns, as monitored on the service unit vacuum gage,
heater surrounding the service unit reservoir is turned on,
for two hours. At the end of two hours evacuation, suction
heating the refrigerant and causing it to expand, increasing
and receiver valves are closed, retaining vacuum in the
the pressure within the reservoir. When the pressure in the
system: then the vacuum pump is shut off and hoses
reservoir has stabilized at approximately 65 psig, the hose
disconnected. It is now necessary to proceed directly to
is purged and tightened at the receiver valve. The
system oil and refrigerant charging operation.
CHARGE valve is opened; then closed. The quantity of
e. Charging Refrigeration System with Oil: The hose
refrigerant contained in the reservoir is noted.
The
assembly, furnished with the service unit, is loosely
receiver valve is opened and the service unit CHARGE
connected to the refrigeration system receiver valve. Air is
valve is controlled to allow the required amount of
purged from the graduated oil fill beaker, using oil used in
refrigerant to enter the refrigeration system, as noted on
the refrigeration system; then the line is tightened on the
the service unit reservoir sight scale. When the proper
receiver valve. The breaker is then filled with enough oil to
amount of refrigerant has entered the refrigeration system,
charge the refrigeration system and have enough oil left
the service unit CHARGE valve is closed; then the receiver
over to prevent air from entering the system. The receiver
valve is closed and the hose is disconnected. The
valve is then closed and the hose assembly disconnected.
refrigeration system is now ready for operation.
f. Charging a Refrigeration System with Refrigerant:
Section I. OPERATING PROCEDURES
2-2.
Preliminary Operating Procedures (See fig. 2-3 and table 2-1.)
2-4
