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24-38
AIR CONDITIONING
REFRIGERANT SERVICE
All 1965 Plymouth units require 2% to 2% pounds
of refrigerant. Three 15 ounce cans of refrigerant 12
provide a complete charge without the necessity
of
weighing the refrigerant as it is dispensed.
NOTE: An accurate scale must
be
used to insure
charging with the proper amount of refrigerant.
Since the use of canned refrigerant is preferred
Use only refrigerant 12 in the 1965 air-condition-
ing system. Refrigerant 12 is available in bulk tanks
or
in sealed 15 ounce cans. The use of canned refrig-
erant is preferred by most technicians because it pro-
vides a very quick and simple means of adding refrig-
erant or
charging the system completely.
universally, only that method is described.
Before the system can be opened for replacement
of lines or components, the system must be completely
discharged. It is also necessary to discharge the
system before performing the Compressor Capacity
Test and the Expansion Valve Test. Whenever the
system has been opened,
it
must be swept with a par-
tial charge, and the entire system tested for leaks. The
drier should be replaced and the system evacuated
using a vacuum pump to remove all air and moisture.
The system should be charged with the proper amount
of refrigerant. Detailed instruction for performing
these operations follow.
DISCHARGE THE SYSTEM
(1) Be sure the valves of the gauge manifold set
are closed before attaching the gauge
set
manifold
(suction
test
hose to the suction service port and dis-
charge
test
hose to the discharge service port). Attach
the long
test
hose to the center connection of the
gauge set manifold. Lead the other end of this hose
into
an
exhaust ventilation system outlet or to the
outside of the building.
(2) Open the gauge set manifold needle valve and
close both of the gauge set manifold gauge valves.
(3) Operate the engine at 1250 rpm with the win-
dows open and the hood up.
(4)
Push in the "Cool" button and turn the blower
to the number 2 position.
(5) Allow the system to operate at full capacity for
at least 15 minutes. This will cause most of the com-
pressor oil in the system to return to the compressor
crankcase.
(6) Open the discharge right-hand gauge valve a
small amount. This will allow the refrigerant vapor
to discharge
slowly.
CAUTION: Do not allow the system to discharge
rapidly since this would sweep some of the refrig-
erant oil out of the compressor.
(7)
Allow the system to discharge until the dis-
charge pressure gauge registers zero. Open the left-
hand valve to release any vapor trapped at the suction
side of the system.
SWEEP-TEST CHARGE
The purpose of the sweep-test charge is to pres-
surize the system so that a leak test can be made. The
sweep-test charge also serves the purpose of drying
the system or sweeping out trapped moisture. Repairs
and component replacement must be completed be-
fore charging with the sweep-test charge.
(1) Close both gauge
set
manifold valves and open
the gauge set manifold needle valve.
(2) Attach the free end of the long hose used for
discharging to the refrigerant dispensing manifold.
(3) Attach a single can of refrigerant 12 to the
dispensing manifold. Place the refrigerant in 125 de-
gree water. For detailed instructions on attaching
re-
frigerant can for charging, see "Charging the System."
(4)
Operate engine at 1250 rpm with the vehicle
doors and windows open and the hood up.
(5) Push in the "Cool" button and
turn
the
blower
to the number 2 position.
(6) Slowly open the left-hand gauge set manifold
valve to meter the refrigerant into the system. When
the full can of refrigerant has been metered into the
system, close the gauge
set
manifold valves and the
refrigerant manifold valve.
If the system has been opened for repair
or re-
placement, a complete leak test must be made to make
sure the system is sealed. Also, if the system has
accidentally lost its charge it will be necessary to per-
form a leak test while the sweep-test charge is in the
system. Stop the engine and disconnect the test hoses
and adapters from the compressor service ports.
TESTING THE SYSTEM FOR LEAKS
The leak detector torch Tool (2-3569 is a propane
gas-burning torch used to locate a leak in any part of
the refrigeration system. Refrigerant gas drawn into
the sampling or "snifter" tube will cause the flame to
change color in proportion to the size of the leak.
A
very small leak will produce a flame color varying
from yellowish-green to bright green.
A
large leak
will produce a brilliant blue flame.
CAUTION: Do not use the lighted detector in any
place where explosive gases, dust, or vapor are
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