Chrysler DODGE D150 1993 Service Manual page 1457

24 - 20 HEATING AND AIR CONDITIONING
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(3) Turn 3 refrigerant manifold valves completely
clockwise to puncture t h e cans and close t h e mani­
fold valves.
(4) Purge t h e air from t h e charging line by loosen­
ing t h e charging hose a t t h e manifold gauge set and
t u r n one of t h e refrigerant valves counterclockwise.
When t h e refrigerant gas starts escaping from the
loose connection, tighten t h e hose.
(5) Fully open all 3 refrigerant manifold valves
and place t h e cans of refrigerant into a p a n contain­
ing 52°C (125°F) water. The water will warm t h e
charging can and aid in t h e transfer of t h e charge
into t h e system.
(6) Start t h e engine and move t h e controls to A/C
low blower position.
The electronic temperature cycling switch will pre­
vent the clutch from engaging until refrigerant is
added to t h e system. If t h e clutch does engage, re­
place t h e switch before proceeding any further.
(7) Charge through t h e suction side of t h e system
by slowly opening the suction manifold valve. Adjust
the valve as necessary so charging pressure does not
exceed 345 kPag (50 psig). Maintain t h e temperature
of t h e water in t h e pan by adding warm water as
necessary.
(8) Adjust t h e engine speed to a fast idle of approx­
imately 1,300 RPM.
(9) When all 3 cans of refrigerant a r e completely
empty, close t h e manifold gauge set valves a n d re­
frigerant manifold valves.
The maximum refrigerant charge is 44 oz.
REFRIGERANT LEAK REPAIR PROCEDURE
LOST CHARGE
If t h e system h a s lost all charge due to a leak:
(1) Evacuate t h e system.
(2) Charge t h e system with approximately 1 pound
of refrigerant.
(3) Locate all leaks.
(4) Repair all leaks.
(5) Replace filter-drier bottle.
C A U T I O N : Replacement filter-drier units must be
sealed while in storage. The drier used in these
units absorbs and traps moisture quickly upon ex­
posure to the atmosphere. When installing a drier,
have all tools a n d supplies ready for quick reas­
sembly to avoid keeping the system open any
longer than necessary.
(6) Check system oil level.
(7) Evacuate and charge t h e system.
LOW CHARGE
If t h e system h a s not lost all of its refrigerant
charge; locate and repair all leaks. If it is necessary
to increase the system pressure to find t h e leak (be­
cause of an especially low charge), add 230 g (1/2 lb)
of refrigerant. If there h a s been a significant oil loss,
check the system oil level. If leak repair was possible
without discharging system and a n oil level check
was not necessary, use procedure for correcting low
refrigerant level.
CORRECTING LOW REFRIGERANT LEVEL
Since the refrigeration system is completely sealed,
the refrigerant level will not be low unless there is a
leak in t h e system.
Before adding refrigerant where the cause of a low
level is not known, the system should be tested for
leaks. Assuming that leaks have been corrected without
discharging the system, proceed with partial charge.
Install and connect manifold gauge set.
(1) Close both manifold gauge set valves. Open
manifold gauge set needle valve.
(2) Connect the suction gauge test hose to t h e suc­
tion service port of the compressor. Connect t h e dis­
charge gauge test hose to the discharge service port.
(3) Connect a n end of long test hose to t h e center
manifold outlet, and other end to refrigerant dispens­
ing manifold.
(4) Close the 2 dispensing manifold valves and
open remaining dispensing manifold valve. Remove
protective cap from opened valve.
W A R N I N G : N E V E R U S E T H E S E C A N S T O C H A R G E
INTO T H E H I G H P R E S S U R E S I D E O F T H E S Y S T E M
( C O M P R E S S O R D I S C H A R G E PORT) O R INTO A
S Y S T E M T H A T I S A T HIGH T E M P E R A T U R E . T H E
H I G H S Y S T E M P R E S S U R E S C O U L D B E T R A N S ­
F E R R E D INTO T H E C H A R G I N G C A N C A U S I N G IT
T O E X P L O D E .
(5) Screw a can of R-12 to t h e opened manifold
valve. Be sure gasket is in place and in good condi­
tion. Tighten refrigerant can and manifold locking
n u t to ensure a good seal. Do not overtighten.
Tighten to 9.5 N*m (7 ft. lbs.) torque, if gasket is in
good condition.
(6) Turn manifold valve (above t h e refrigerant can)
completely clockwise to puncture the can. This closes
the valve and seals t h e refrigerant in t h e can.
C A U T I O N : D o not heat refrigerant 12 above 52°C
(125°F).
(7) Place refrigerant can in a large pan of water
heated to 52°C (125°F). Place p a n of water containing
the refrigerant can on a n accurate scale so t h e
amount of refrigerant added can be weighed. Open
the refrigerant manifold valve.
(8) Purge all air from test hoses. Air in t h e system
will be trapped in t h e condenser causing abnormally
high discharge pressures and interfering with con­
densing of t h e refrigerant.