TM 9-4120-357-14
(1) Remove four screws and washers from the casing and side-mounting brackets, and remove two screws and
washers from the inner mounting bracket.
(2) Debraze the tubing connection, and remove the accumulator tank(s) (10 & 11) .
d. Installation. Install the accumulator tank(s) as follows:
(1) Fit tubing into the tank connection, and attach the mounting flanges to the casing and the inner mounting bracket
with six screws and washers, finger tight.
(2) With dry nitrogen flowing through the system, braze the tubing connection.
(3) Tighten the six mounting screws.
e. Purging the System.
CAUTION
Whenever the refrigeration system has been opened to the atmosphere, you must install a
new drier-strainer (dehydrator) before purging and recharging the system.
With the refrigeration system discharged and a hose attached to the gage port of the suction service valve, connect a
cylinder of oil-pumped dry nitrogen to the gage port of the high-pressure service valve. Open the high-pressure service
valve, and crack open the cylinder shutoff valve to establish a flow of 1-2 CFM (0.5 - 1 M3) through the system. Purge
for at least 30 minutes to expel all other gases, impurities and water vapor. Turn off both service valves before discon-
necting the nitrogen cylinder and the discharge hose.
f. Charging the System. Prepare the refrigeration system for charging by attaching a pressure gage to the high-
pressure service valve gage port, and a pressure hose and drier-strainer, loosely, to the suction service valve gage
port. Leave both valves closed. Proceed as follows:
WARNING
Avoid contact with liquid refrigerant or escaping refrigerant gas. Irreversible tissue dam-
age can result from sudden freezing. Be especially careful to protect the eyes. Avoid in-
haling high concentrations of refrigerant gas, and prevent gas coming into direct contact
with flame or hot metal surfaces; lethal phosgene gas can be formed.
(1) Connect a cylinder of refrigerant, R22, to the pressure hose. Open the cylinder shutoff valve slightly to purge the
hose of air, then tighten the hose connection to the suction service valve gage port.
(2) Open both service valves and the cylinder shutoff valve, and charge the system with refrigerant gas until the
gage on the discharge (high-pressure) service valve registers 70 PSI (5 KG/CM2) . Close the suction service valve and
the cylinder shutoff valve.
(3) Transfer the charging line to a cylinder of dry nitrogen. Open the cylinder shutoff valve and suction service valve,
and let nitrogen flow into the refrigeration system until the discharge pressure gage reads 350 PSI (21.44 KG/CM2) .
Close the suction and discharge service valves and cylinder shutoff valve. Disconnect the charging line from suction
service valve.
(4) Test the refrigeration system for leaks, using an electronic leak detector, Halide torch or soap bubble method.
CAUTION
The electronic leak detector and the Halide torch are sensitive to the presence of refriger-
ant gas in the atmosphere. When refrigerant gas is present in the atmosphere of the work
area, false indications can result. Use in a well ventilated but draft-free area.
(a) Electronic Leak Detector. Turn the electronic unit on, and slowly pass the probe around all points of the refrig-
eration system at which a leak could exist. Depending upon the type of detector used, a leak will be indicated by an
audible signal, a light, or by meter deflections.
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