2002 DODGE RAM service

(3) Be certain that the blower motor seal is
installed on the blower motor housing (Fig. 5).
(4) Install the blower motor and wheel assembly,
and cover in the HVAC housing with three mounting
screws. Tighten the mounting screws to 2.2 N´m (20
in. lbs.).
(5) Plug the blower motor wire harness connector
into the HVAC housing wire harness.
(6) Install the blower motor wire harness into the
wire harness retainer.
(7) Connect the blower motor cooling tube to the
nipple on the blower motor housing.
(8) Connect the battery negative cable.
DEFROSTER DUCTS
REMOVAL - DEFROSTER AND DEMISTER
DUCTS
The defroster duct and the main demister duct are
a single molded plastic unit. The defroster outlet
grilles are heat-staked to the defroster outlets and
cannot be serviced separately. The demister tubes on
each end of the main demister duct are only serviced
in the instrument panel assembly.
(1) Remove the instrument panel top cover from
the instrument panel(Refer to 23 - BODY/INSTRU-
MENT PANEL/INSTRUMENT PANEL TOP COVER
- REMOVAL).
(2) Remove the screws that secure the defroster
and demister ducts to the instrument panel brackets
(Fig. 6).
(3) Disengage the demister tubes from each end of
the main demister duct.
(4) Remove the defroster and demister duct unit
from the instrument panel.
REMOVAL - DEFROSTER AND DEMISTER
DUCT ADAPTER
(1) Roll the instrument panel assembly down, but
do not remove it from the vehicle(Refer to 23 -
BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL ASSEMBLY - REMOVAL).
(2) Using a trim stick or another suitable wide
flat-bladed tool, gently pry at the perimeter edges of
the defroster and demister duct adapter to release
the snap features from the top of the HVAC housing
(Fig. 7).
(3) Remove the defroster and demister duct
adapter from the top of the HVAC housing.
INSTALLATION - DEFROSTER AND DEMISTER
DUCTS
(1) Place the defroster and demister duct unit in
position.
(2) Engage the demister tubes with each end of
the main demister duct.
(3) Install the screws that secure the defroster and
demister ducts to the instrument panel brackets.
Tighten the mounting screws to 2.2 N´m (20 in. lbs.).
(4) Install the instrument panel top cover on the
instrument panel(Refer to 23 - BODY/INSTRUMENT
PANEL/INSTRUMENT PANEL TOP COVER -
INSTALLATION).
INSTALLATION - DEFROSTER AND DEMISTER
DUCT ADAPTER
(1) Snap the defroster and demister duct adapter
from the top of the HVAC housing.
Fig. 4 BLOWER MOTOR WHEEL REMOVE/INSTALL
1 - BLOWER MOTOR WHEEL
2 - RETAINER CLIP
Fig. 5 BLOWER MOTOR SEAL
1 - BLOWER MOTOR SEAL
BR/BEDISTRIBUTION 24 - 33
BLOWER MOTOR (Continued)

(2) Roll the instrument panel assembly up, and
fasten it properly to the vehicle(Refer to 23 - BODY/
INSTRUMENT PANEL/INSTRUMENT PANEL
ASSEMBLY - INSTALLATION).
HVAC HOUSING
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
WARNING: IF THE VEHICLE IS EQUIPPED WITH AIR
CONDITIONING, REVIEW THE WARNINGS AND
CAUTIONS IN PLUMBING BEFORE PERFORMING
THE FOLLOWING OPERATION. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - WARNING)
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - CAUTION)
The HVAC housing assembly must be removed
from the vehicle and disassembled for service access
of the heater core, a/c evaporator, and each of the
various mode control doors.
Fig. 6 DEFROSTER AND DEMISTER DUCT
1 - DEMISTER TUBE
2 - INSTRUMENT PANEL TOP COVER3 - BRACKETS
4 - DEFROSTER AND DEMISTER DUCT
Fig. 7 DEFROSTER AND DEMISTER DUCT
ADAPTER REMOVE/INSTALL
1 - DEFROSTER AND DEMISTER DUCT ADAPTER
2 - HEATER-A/C HOUSING
24 - 34 DISTRIBUTIONBR/BE
DEFROSTER DUCTS (Continued)

(5) Place the HVAC housing right side up on the
work bench.
(6) Separate the top half of the HVAC housing
from the bottom half and set it aside.
ASSEMBLY
(1) Position the top half of the HVAC housing over
the bottom half. Be certain that the mode door pivot
pins are properly inserted in their pivot holes.
(2) Place the HVAC housing upside down on the
work bench.
(3) Install and tighten the screws on the bottom of
the HVAC housing that secure the two housing
halves together. Tighten the screws to 2.2 N´m (20 in.
lbs.).
(4) Snap the center heat duct adaptor onto the bot-
tom of the HVAC housing.
(5) Slide the floor duct onto the center heat duct
adaptor and secure it with a screw to the bottom of
the HVAC housing. Tighten the mounting screw to
2.2 N´m (20 in. lbs.).
INSTALLATION
(1) Position the HVAC housing to the dash panel.
Be certain that the evaporator condensate drain tube
and the housing mounting studs are inserted into
their correct mounting holes.
(2) Install the nuts that secure the HVAC housing
to the mounting studs on the passenger compartment
side of the dash panel. Tighten the nuts to 4.5 N´m
(40 in. lbs.).
(3) Install and tighten the nuts onto the HVAC
housing mounting studs on the engine compartment
side of the dash panel. Tighten the nuts to 7 N´m (60
in. lbs.).
(4) Unplug or remove the tape from the heater
core tubes. Connect the heater hoses to the heater
core tubes and fill the engine cooling system(Refer to
7 - COOLING - STANDARD PROCEDURE) and
(Refer to 7 - COOLING - STANDARD PROCE-
DURE).
(5) If the vehicle is not equipped with air condi-
tioning, go to Step 10. If the vehicle is equipped with
air conditioning, install the accumulator. (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING/
ACCUMULATOR - INSTALLATION) Connect the
accumulator inlet tube coupler to the evaporator out-
let tube. (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - STANDARD PROCEDURE -
A/C LINE COUPLERS)
(6) Unplug or remove the tape from the liquid line
and the evaporator inlet tube fittings. Connect the
liquid line coupler to the evaporator inlet tube. (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMB-
ING - STANDARD PROCEDURE - A/C LINE COU-
PLERS)(7) Evacuate the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM EVACUATE)
(8) Charge the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM CHARGE)
(9) Reinstall the PCM to the dash panel. Refer to
Electronic Control Modules for the procedures.
(10) Reinstall the instrument panel in the vehi-
cle(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY -
INSTALLATION).
(11) Connect the battery negative cable.
(12) Start the engine and check for proper opera-
tion of the heating and air conditioning systems.
INSTALLATION - HVAC HOUSING INLET
BAFFLE
(1) Install the HVAC housing inlet baffle in the
cowl plenum panel.
(2) Slide the HVAC housing inlet baffle to engage
the snap features.
(3) Make certain that the snap features on each
side of the adapter are fully engaged with the sides
of the plenum panel opening. This must be a water
tight connection to prevent leaks.
(4) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
INSTRUMENT PANEL
DEMISTER DUCTS
REMOVAL
The defroster duct and the main demister duct are
a single molded plastic unit. The defroster outlet
grilles are heat-staked to the defroster outlets and
cannot be serviced separately. The demister tubes on
each end of the main demister duct are only serviced
in the instrument panel assembly. (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
DEFROSTER DUCTS - REMOVAL)
INSTALLATION
The defroster duct and the main demister duct are
a single molded plastic unit. The defroster outlet
grilles are heat-staked to the defroster outlets and
cannot be serviced separately. The demister tubes on
each end of the mail demister duct are only serviced
in the instrument panel assembly(Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
DEFROSTER DUCTS - INSTALLATION).
24 - 36 DISTRIBUTIONBR/BE
HVAC HOUSING (Continued)

INSTRUMENT PANEL DUCTS
REMOVAL
The panel and center distribution ducts (Fig. 10)
are only serviced as part of the instrument panel
assembly. Refer to Instrument Panel System for the
service procedures.
INSTALLATION
The panel and center distribution ducts are only
serviced as part of the instrument panel assembly.
Refer to Instrument Panel System for the service
procedures.
BLEND DOOR
REMOVAL
(1) Remove the HVAC housing from the vehicle,
and disassemble the housing halves. (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - REMOVAL) (Refer to 24 - HEAT-
ING & AIR CONDITIONING/DISTRIBUTION/HVAC
HOUSING - DISASSEMBLY)(2) Lift the blend door pivot shaft out of the pivot
hole in the bottom of the HVAC housing (Fig. 11).
INSTALLATION
(1) Install the blend door pivot shaft in the bottom
of the HVAC housing.
(2) Assemble the HVAC housing. (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - ASSEMBLY)
(3) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
MODE DOOR
REMOVAL - HEAT/DEFROST DOOR
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
Fig. 10 PANEL AND CENTER DISTRIBUTION DUCTS
1 - BRACKET
2 - SCREW
3 - CENTER DISTRIBUTION DUCT
4 - SCREW
5 - PANEL DUCTS
Fig. 11 BLEND DOOR
1 - HEAT/DEFROST DOOR
2 - TEMP/BLEND AIR DOOR
BR/BEDISTRIBUTION 24 - 37

WARNING: IF THE VEHICLE IS EQUIPPED WITH AIR
CONDITIONING, REVIEW THE WARNINGS AND
CAUTIONS IN PLUMBING BEFORE PERFORMING
THE FOLLOWING OPERATION. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - WARNING)
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - CAUTION)
(1) Remove and disassemble the HVAC housing.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - DISASSEMBLY)
(2) Remove the heat/defrost door actuator from the
HVAC housing. (Refer to 24 - HEATING & AIR CON-
DITIONING/CONTROLS/MODE DOOR ACTUATOR
- REMOVAL)
(3) Remove the heat/defrost door from the HVAC
housing.
REMOVAL - PANEL/DEFROST DOOR
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the instrument panel assembly from
the vehicle(Refer to 23 - BODY/INSTRUMENT PAN-
EL/INSTRUMENT PANEL ASSEMBLY - REMOV-
AL).
(3) Remove the panel/defrost door actuator from
the HVAC housing. (Refer to 24 - HEATING & AIR
CONDITIONING/CONTROLS/MODE DOOR
ACTUATOR - REMOVAL)
(4) Remove the defroster and demister duct
adapter from the HVAC housing. ***L***
(5) Lift the panel/defrost door out of the top open-
ing of the HVAC housing.
INSTALLATION - HEAT/DEFROST DOOR
(1) Install the heat/defrost door in the HVAC hous-
ing.(2) Assemble the HVAC housing. (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - ASSEMBLY)
(3) Install the heat/defrost door actuator on the
HVAC housing. (Refer to 24 - HEATING & AIR CON-
DITIONING/CONTROLS/MODE DOOR ACTUATOR
- INSTALLATION)
(4) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
INSTALLATION - PANEL/DEFROST DOOR
(1) Install the panel/defrost door through the top
opening of the HVAC housing.
(2) Install the defroster and demister duct adapter
on the HVAC housing. (Refer to 24 - HEATING &
AIR CONDITIONING/DISTRIBUTION/DEFROSTER
DUCTS - INSTALLATION)
(3) Install the panel/defrost door actuator on the
HVAC housing. (Refer to 24 - HEATING & AIR CON-
DITIONING/CONTROLS/MODE DOOR ACTUATOR
- REMOVAL)
(4) Install the instrument panel assembly in the
vehicle(Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL ASSEMBLY - INSTALLA-
TION).
(5) Connect the battery negative cable.
RECIRCULATION DOOR
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
WARNING: IF THE VEHICLE IS EQUIPPED WITH AIR
CONDITIONING, REVIEW THE WARNINGS AND
CAUTIONS IN PLUMBING BEFORE PERFORMING
THE FOLLOWING OPERATION. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - WARNING)
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - CAUTION)
24 - 38 DISTRIBUTIONBR/BE
MODE DOOR (Continued)

PLUMBING
TABLE OF CONTENTS
page page
PLUMBING
DESCRIPTION..........................40
OPERATION............................41
WARNING..............................42
CAUTION..............................42
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM LEAKS.......................43
STANDARD PROCEDURE
STANDARD PROCEDURE - A/C LINE
COUPLERS...........................44
STANDARD PROCEDURE - REFRIGERANT
SYSTEM SERVICE EQUIPMENT...........45
STANDARD PROCEDURE - REFRIGERANT
RECOVERY...........................45
STANDARD PROCEDURE - REFRIGERANT
SYSTEM EVACUATE....................46
STANDARD PROCEDURE - REFRIGERANT
SYSTEM CHARGE......................46
SPECIFICATIONS........................46
A/C COMPRESSOR
DESCRIPTION..........................46
OPERATION............................46
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - A/C
COMPRESSOR........................47
REMOVAL..............................47
INSTALLATION..........................48
A/C CONDENSER
DESCRIPTION..........................49
OPERATION............................49
REMOVAL..............................49
INSTALLATION..........................50
SUCTION AND DISCHARGE LINE
REMOVAL..............................51
INSTALLATION..........................52LIQUID LINE
REMOVAL..............................52
INSTALLATION..........................52
A/C EVAPORATOR
DESCRIPTION..........................53
OPERATION............................53
REMOVAL..............................53
INSTALLATION..........................53
A/C ORIFICE TUBE
DESCRIPTION..........................54
OPERATION............................54
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - FIXED
ORIFICE TUBE.........................54
REMOVAL..............................54
INSTALLATION..........................54
ACCUMULATOR
DESCRIPTION..........................55
OPERATION............................55
REMOVAL..............................55
INSTALLATION..........................55
HEATER CORE
DESCRIPTION..........................56
OPERATION............................56
REMOVAL..............................56
INSTALLATION..........................56
REFRIGERANT
DESCRIPTION..........................56
OPERATION............................57
REFRIGERANT OIL
DESCRIPTION..........................57
OPERATION............................57
STANDARD PROCEDURE
STANDARD PROCEDURE - REFRIGERANT
OIL LEVEL............................57
PLUMBING
DESCRIPTION - A/C LINE COUPLERS
Spring-lock type refrigerant line couplers are used
to connect many of the refrigerant lines and other
components to the refrigerant system. These couplers
require a special tool for disengaging the two coupler
halves.
DESCRIPTION- REFRIGERANT LINES
The refrigerant lines and hoses are used to carry
the refrigerant between the various air conditioning
system components. A barrier hose design with a
nylon tube, which is sandwiched between rubber lay-
ers, is used for the R-134a air conditioning system on
this vehicle. This nylon tube helps to further contain
the R-134a refrigerant, which has a smaller molecu-
lar structure than R-12 refrigerant. The ends of the
refrigerant hoses are made from lightweight alumi-
num or steel, and commonly use braze-less fittings.
24 - 40 PLUMBINGBR/BE

SERVICE WARNINGS
WARNING:
THE AIR CONDITIONING SYSTEM CONTAINS
REFRIGERANT UNDER HIGH PRESSURE. SEVERE
PERSONAL INJURY MAY RESULT FROM IMPROPER
SERVICE PROCEDURES. REPAIRS SHOULD ONLY
BE PERFORMED BY QUALIFIED SERVICE PERSON-
NEL.
AVOID BREATHING THE REFRIGERANT AND
REFRIGERANT OIL VAPOR OR MIST. EXPOSURE
MAY IRRITATE THE EYES, NOSE, AND/OR THROAT.
WEAR EYE PROTECTION WHEN SERVICING THE
AIR CONDITIONING REFRIGERANT SYSTEM. SERI-
OUS EYE INJURY CAN RESULT FROM DIRECT
CONTACT WITH THE REFRIGERANT. IF EYE CON-
TACT OCCURS, SEEK MEDICAL ATTENTION IMME-
DIATELY.
DO NOT EXPOSE THE REFRIGERANT TO OPEN
FLAME. POISONOUS GAS IS CREATED WHEN
REFRIGERANT IS BURNED. AN ELECTRONIC LEAK
DETECTOR IS RECOMMENDED.
IF ACCIDENTAL SYSTEM DISCHARGE OCCURS,
VENTILATE THE WORK AREA BEFORE RESUMING
SERVICE. LARGE AMOUNTS OF REFRIGERANT
RELEASED IN A CLOSED WORK AREA WILL DIS-
PLACE THE OXYGEN AND CAUSE SUFFOCATION.
THE EVAPORATION RATE OF R-134a REFRIGER-
ANT AT AVERAGE TEMPERATURE AND ALTITUDE
IS EXTREMELY HIGH. AS A RESULT, ANYTHING
THAT COMES IN CONTACT WITH THE REFRIGER-
ANT WILL FREEZE. ALWAYS PROTECT THE SKIN
OR DELICATE OBJECTS FROM DIRECT CONTACT
WITH THE REFRIGERANT.
THE R-134a SERVICE EQUIPMENT OR THE VEHI-
CLE REFRIGERANT SYSTEM SHOULD NOT BE
PRESSURE TESTED OR LEAK TESTED WITH COM-
PRESSED AIR. SOME MIXTURES OF AIR AND
R-134a HAVE BEEN SHOWN TO BE COMBUSTIBLE
AT ELEVATED PRESSURES. THESE MIXTURES ARE
POTENTIALLY DANGEROUS, AND MAY RESULT IN
FIRE OR EXPLOSION CAUSING INJURY OR PROP-
ERTY DAMAGE.
SERVICE CAUTIONS
CAUTION: Liquid refrigerant is corrosive to metal
surfaces. Follow the operating instructions supplied
with the service equipment being used.
Never add R-12 to a refrigerant system designed to
use R-134a. Damage to the system will result.
R-12 refrigerant oil must not be mixed with R-134a
refrigerant oil. They are not compatible.
Do not use R-12 equipment or parts on the R-134a
system. Damage to the system will result.Do not overcharge the refrigerant system. This will
cause excessive compressor head pressure and
can cause noise and system failure.
Recover the refrigerant before opening any fitting
or connection. Open the fittings with caution, even
after the system has been discharged. Never open
or loosen a connection before recovering the refrig-
erant.
Do not remove the secondary retention clip from
any spring-lock coupler connection while the refrig-
erant system is under pressure. Recover the refrig-
erant before removing the secondary retention clip.
Open the fittings with caution, even after the sys-
tem has been discharged. Never open or loosen a
connection before recovering the refrigerant.
The refrigerant system must always be evacuated
before charging.
Do not open the refrigerant system or uncap a
replacement component until you are ready to ser-
vice the system. This will prevent contamination in
the system.
Before disconnecting a component, clean the out-
side of the fittings thoroughly to prevent contami-
nation from entering the refrigerant system.
Immediately after disconnecting a component from
the refrigerant system, seal the open fittings with a
cap or plug.
Before connecting an open refrigerant fitting,
always install a new seal or gasket. Coat the fitting
and seal with clean refrigerant oil before connect-
ing.
Do not remove the sealing caps from a replacement
component until it is to be installed.
When installing a refrigerant line, avoid sharp
bends that may restrict refrigerant flow. Position the
refrigerant lines away from exhaust system compo-
nents or any sharp edges, which may damage the
line.
Tighten refrigerant fittings only to the specified
torque. The aluminum fittings used in the refriger-
ant system will not tolerate overtightening.
When disconnecting a refrigerant fitting, use a
wrench on both halves of the fitting. This will pre-
vent twisting of the refrigerant lines or tubes.
Refrigerant oil will absorb moisture from the atmo-
sphere if left uncapped. Do not open a container of
refrigerant oil until you are ready to use it. Replace
the cap on the oil container immediately after using.
Store refrigerant oil only in a clean, airtight, and
moisture-free container.
Keep service tools and the work area clean. Con-
tamination of the refrigerant system through care-
less work habits must be avoided.
24 - 42 PLUMBINGBR/BE
PLUMBING (Continued)

CAUTION - REFRIGERANT HOSES/LINES/
TUBES PRECAUTIONS
Kinks or sharp bends in the refrigerant plumbing
will reduce the capacity of the entire system. High
pressures are produced in the system when it is oper-
ating. Extreme care must be exercised to make sure
that all refrigerant system connections are pressure
tight.
A good rule for the flexible hose refrigerant lines is
to keep the radius of all bends at least ten times the
diameter of the hose. Sharp bends will reduce the
flow of refrigerant. The flexible hose lines should be
routed so they are at least 80 millimeters (3 inches)
from the exhaust manifold. It is a good practice to
inspect all flexible refrigerant system hose lines at
least once a year to make sure they are in good con-
dition and properly routed.
There are two types of refrigerant fittings:
²All fittings with O-rings need to be coated with
refrigerant oil before installation. Use only O-rings
that are the correct size and approved for use with
R-134a refrigerant. Failure to do so may result in a
leak.
²Unified plumbing connections with gaskets can-
not be serviced with O-rings. The gaskets are not
reusable and new gaskets do not require lubrication
before installing.
Using the proper tools when making a refrigerant
plumbing connection is very important. Improper
tools or improper use of the tools can damage the
refrigerant fittings. Always use two wrenches when
loosening or tightening tube fittings. Use one wrench
to hold one side of the connection stationary, while
loosening or tightening the other side of the connec-
tion with a second wrench.
The refrigerant must be recovered completely from
the system before opening any fitting or connection.
Open the fittings with caution, even after the refrig-
erant has been recovered. If any pressure is noticed
as a fitting is loosened, tighten the fitting and
recover the refrigerant from the system again.
Do not discharge refrigerant into the atmosphere.
Use an R-134a refrigerant recovery/recycling device
that meets SAE Standard J2210.
The refrigerant system will remain chemically sta-
ble as long as pure, moisture-free R-134a refrigerant
and refrigerant oil is used. Dirt, moisture, or air can
upset this chemical stability. Operational troubles or
serious damage can occur if foreign material is
present in the refrigerant system.
When it is necessary to open the refrigerant sys-
tem, have everything needed to service the system
ready. The refrigerant system should not be left open
to the atmosphere any longer than necessary. Cap or
plug all lines and fittings as soon as they are opened
to prevent the entrance of dirt and moisture. All linesand components in parts stock should be capped or
sealed until they are to be installed.
All tools, including the refrigerant recycling equip-
ment, the manifold gauge set, and test hoses should
be kept clean and dry. All tools and equipment must
be designed for R-134a refrigerant.
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM LEAKS
WARNING: (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - WARNING) (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING - CAU-
TION) BEFORE PERFORMING THE FOLLOWING
OPERATION.
If the air conditioning system is not cooling prop-
erly, determine if the refrigerant system is fully-
charged. (Refer to 24 - HEATING & AIR
CONDITIONING - DIAGNOSIS AND TESTING -
A/C PERFORMANCE) If the refrigerant system is
low or empty; a leak at a refrigerant line, connector
fitting, component, or component seal is likely.
An electronic leak detector designed for R-134a
refrigerant, or a fluorescent R-134a leak detection
dye and a black light are recommended for locating
and confirming refrigerant system leaks. Refer to the
operating instructions supplied by the equipment
manufacturer for proper care and use of this equip-
ment.
An oily residue on or near refrigerant system lines,
connector fittings, components, or component seals
can indicate the general location of a possible refrig-
erant leak. However, the exact leak location should
be confirmed with an electronic leak detector prior to
component repair or replacement.
To detect a leak in the refrigerant system with an
electronic leak detector, perform one of the following
procedures:
SYSTEM EMPTY
(1) Evacuate the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM EVACUATE)
(2) Connect and dispense 0.283 kilograms (0.625
pounds or 10 ounces) of R-134a refrigerant into the
evacuated refrigerant system. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - STAN-
DARD PROCEDURE - REFRIGERANT SYSTEM
CHARGE)
(3) Position the vehicle in a wind-free work area.
This will aid in detecting small leaks.
(4) With the engine not running, use a electronic
R-134a leak detector and search for leaks. Because
R-134a refrigerant is heavier than air, the leak detec-
BR/BEPLUMBING 24 - 43
PLUMBING (Continued)