2003 CHRYSLER CARAVAN heater

(2) Drain the engine cooling system. (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM DRAIN).
(3) Disconnect and isolate the battery negative
cable.
(4) Raise and support the vehicle.
(5) Disconnect the underbody refrigerant line seal-
ing plate from the rear heater-A/C unit evaporator
extension line sealing plate that extends through the
rear floor panel behind the right rear wheel housing
(Fig. 6).
(6) Remove the seals from the liquid line and suc-
tion line fittings and discard.
(7) Install plugs in, or tape over the opened liquid
line and suction line fittings and both ports in the
evaporator extension line sealing plate.
(8) Remove the three nuts that secure the rear
heater-A/C unit mounting studs to the rear floor
panel behind the right rear wheel housing (Fig. 7).
(9) Lower the vehicle.
(10) Remove the right quarter trim panel and
right D-pillar trim panel from the quarter inner
panel. (Refer to 23 - BODY/INTERIOR/QUARTER
TRIM PANEL - REMOVAL).
(11) Remove the rear A/C distribution duct from
the rear heater-A/C unit and the rear roof duct.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION - REAR/AUXILIARY A/C DISTRI-
BUTION DUCT - REMOVAL).
(12) Disconnect the body wire harness connector
for the rear heater-A/C unit housing from the rear
HVAC wire harness connector located near the
expansion valve at the back of the unit.
(13) Remove the two screws that secure the top of
the quarter trim panel attaching bracket to the quar-
ter inner panel.(14) Remove the two screws that secure the bottom
of the quarter trim panel attaching bracket to the
rear heater-A/C unit housing.
(15) Remove the rear heater distribution duct from
the right quarter inner panel. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/DISTRIBUTION -
REAR/REAR HEATER DISTRIBUTION DUCT -
REMOVAL).
(16) Take the proper precautions to protect the
carpeting below the rear heater core from spilled
engine coolant and have absorbent toweling readily
available to clean up any spills.
(17) Disconnect the heater hoses at the rear heater
core. (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - REAR/HEATER HOSE - REMOV-
AL).
(18) Install plugs in, or tape over the opened
heater core fittings and both heater hoses.
(19) Use absorbent toweling to mop up any engine
coolant spills from the preceding operation.
(20) Remove the screw that secures the back of the
rear heater-A/C unit housing to the right D-pillar
(Fig. 8).
(21) Remove the screw that secures the front of
the rear heater-A/C unit housing to the right quarter
inner panel.
(22) Lift the rear heater-A/C unit housing up far
enough for the lower mounting studs and the evapo-
rator extension lines to clear the mounting holes in
the rear floor panel.
(23) Remove the rear heater-A/C unit housing from
the vehicle.
(24) Use absorbent toweling to mop up any engine
coolant spills from the preceding operation.
Fig. 6 Refrigerant Lines
1 - UNDERBODY REFRIGERANT LINE SEALING PLATE
Fig. 7 Rear Heater-A/C Unit Mounting Studs
1 - REAR HEATER-A/C UNIT MOUNTING STUDS
RSDISTRIBUTION - REAR24-57
REAR HEATER-A/C HOUSING (Continued)
ProCarManuals.com

INSTALLATION
NOTE: If the rear heater core or the rear heater-A/C
housing have been removed from the vehicle for
service, the rear heater core may be pre-filled with
the proper engine coolant mixture prior to recon-
necting the heater hoses to the heater core hose fit-
tings. (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - REAR/HEATER CORE - STANDARD
PROCEDURE - HEATER CORE FILLING).
(1) Position the rear heater-A/C unit housing into
the vehicle with the evaporator extension line sealing
plate inserted into the rectangular hole in the rear
floor panel behind the right rear wheel house.
(2) Align the rear heater-A/C unit housing lower
mounting studs with the mounting holes in the rear
floor panel and lower the unit to the floor.
(3) Install and tighten the screw that secures the
front of the rear heater-A/C unit housing to the right
quarter inner panel. Tighten the screw to 11 N´m (97
in. lbs.).(4) Install and tighten the screw that secures the
back of the rear heater-A/C unit housing to the right
D-pillar. Tighten the screw to 11 N´m (97 in. lbs.).
(5) Remove the plugs or tape from both heater core
fittings and both heater hoses.
(6) Reconnect the heater hoses to the rear heater
core. (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - REAR/HEATER HOSE - INSTAL-
LATION).
(7) Reinstall the rear heater distribution duct onto
the right quarter inner panel. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/DISTRIBUTION -
REAR/REAR HEATER DISTRIBUTION DUCT -
INSTALLATION).
(8) Install and tighten the two screws that secure
the bottom of the quarter trim panel attaching
bracket to the rear heater-A/C unit housing. Tighten
the screws to 1.7 N´m (15 in. lbs.).
(9) Install and tighten the two screws that secure
the top of the quarter trim panel attaching bracket to
the quarter inner panel.
Fig. 8 Rear Heater-A/C Housing
1 - U-NUT (3)
2 - REAR HEATER-A/C HOUSING
3 - SCREW (3)
4 - EXPANSION VALVE5 - STUD (3)
6 - HEATER LINES
7 - NUT (5)
8 - STUD (2)
24 - 58 DISTRIBUTION - REARRS
REAR HEATER-A/C HOUSING (Continued)
ProCarManuals.com

(10) Reconnect the body wire harness connector for
the rear heater-A/C unit housing to the rear HVAC
wire harness connector located near the expansion
valve at the back of the unit.
(11) Reinstall the auxiliary A/C distribution duct
onto the rear heater-A/C unit and the rear roof duct.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION - REAR/AUXILIARY A/C DISTRI-
BUTION DUCT - INSTALLATION).
(12) Reinstall the right quarter trim panel and
right D-pillar trim panel onto the quarter inner
panel. (Refer to 23 - BODY/INTERIOR/QUARTER
TRIM PANEL - INSTALLATION).
(13) Raise and support the vehicle.
(14) Install and tighten the three nuts that secure
the rear heater-A/C unit mounting studs to the rear
floor panel behind the right rear wheel housing.
Tighten the nuts to 9 N´m (80 in. lbs.).
(15) Remove the tape or plugs from the underbody
liquid line and suction line fittings and both ports in
the rear heater-A/C unit evaporator extension line
sealing plate that extends through the rear floor
panel behind the right rear wheel housing.
(16) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the liquid line and
suction line fittings.
(17) Reconnect the underbody refrigerant line seal-
ing plate to the evaporator extension line sealing
plate.
(18) Install and tighten the screw that secures the
underbody refrigerant line sealing plate to the evap-
orator extension line sealing plate. Tighten the screw
to 23 N´m (17 ft. lbs.).
(19) Lower the vehicle.
(20) Reconnect the battery negative cable.
(21) Refill the engine cooling system. (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
(22) Evacuate the refrigerant system. (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(23) Charge the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
(24) Run the HVAC Cooldown test to verify proper
operation(Refer to 24 - HEATING & AIR CONDI-
TIONING - DIAGNOSIS AND TESTING).REAR HEATER DISTRIBUTION
DUCT
REMOVAL
(1) Remove the trim from the right quarter inner
panel. (Refer to 23 - BODY/INTERIOR/RIGHT
QUARTER TRIM PANEL - REMOVAL).
(2) Remove the two screws that secure the rear
heater distribution duct to the right quarter inner
panel (Fig. 9).
(3) Slide the rear heater distribution duct forward
far enough to disengage it from the outlet on the
front of the rear heater-air conditioner unit housing.
(4) Remove the rear heater distribution duct from
the vehicle.
INSTALLATION
(1) Align the inlet end of rear heater distribution
duct with the outlet on the front of the rear heater-
air conditioner unit housing.
(2) Slide the rear heater distribution duct rear-
ward far enough to fully engage the inlet end of the
duct with the outlet on the front of the rear heater-
air conditioner unit housing.
(3) Install and tighten the two screws that secure
the rear heater distribution duct to the right quarter
inner panel. Tighten the screws to 1.6 N´m (14 in.
lbs.).
(4) Reinstall the trim onto the right quarter inner
panel. (Refer to 23 - BODY/INTERIOR/RIGHT
QUARTER TRIM PANEL - INSTALLATION).
Fig. 9 Rear Heater Distribution Duct
1 - REAR HEATER DISTRIBUTION DUCT
2 - REAR HEATER-A/C UNIT OUTLET
3 - SCREW (2)
RSDISTRIBUTION - REAR24-59
REAR HEATER-A/C HOUSING (Continued)
ProCarManuals.com

PLUMBING - FRONT
TABLE OF CONTENTS
page page
PLUMBING - FRONT
WARNING
WARNING...........................61
WARNING - A/C PLUMBING.............61
CAUTION - A/C PLUMBING...............61
A/C COMPRESSOR
DESCRIPTION.........................63
OPERATION...........................63
DIAGNOSIS AND TESTING - COMPRESSOR
NOISE DIAGNOSIS....................63
REMOVAL
REMOVAL - COMPRESSOR - 2.4/3.3/3.8L
ENGINES............................64
REMOVAL - COMPRESSOR MOUNTING
BRACKET - 2.4L ENGINE...............65
INSTALLATION
INSTALLATION - COMPRESSOR..........65
INSTALLATION - COMPRESSOR
MOUNTING BRACKET - 2.4L ENGINE......66
CONDENSER
DESCRIPTION.........................66
OPERATION...........................66
REMOVAL.............................66
INSTALLATION.........................67
DISCHARGE LINE
REMOVAL.............................68
INSTALLATION.........................69
EVAPORATOR
DESCRIPTION.........................69
OPERATION...........................70
REMOVAL.............................70
INSTALLATION.........................71
EXPANSION VALVE
DESCRIPTION.........................72
OPERATION...........................72
DIAGNOSIS AND TESTING - EXPANSION
VALVE ..............................72
REMOVAL.............................73
INSTALLATION.........................74
HEATER CORE
DESCRIPTION.........................74
OPERATION...........................74
REMOVAL
REMOVAL- HEATER CORE EXTENSION
TUBES.............................75REMOVAL - HEATER CORE.............76
INSTALLATION
INSTALLATION- HEATER CORE
EXTENSION TUBES...................77
INSTALLATION - HEATER CORE..........78
HEATER HOSE
REMOVAL.............................78
INSTALLATION.........................80
LIQUID LINE
REMOVAL.............................80
INSTALLATION.........................82
RECEIVER/DRIER
DESCRIPTION.........................83
OPERATION...........................84
REMOVAL.............................84
INSTALLATION.........................84
REFRIGERANT
DESCRIPTION.........................85
OPERATION...........................85
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM CHARGE LEVEL...............85
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM LEAKS......................86
STANDARD PROCEDURE
STANDARD PROCEDURE - REFRIGERANT
SYSTEM SERVICE EQUIPMENT..........87
STANDARD PROCEDURE - REFRIGERANT
SYSTEM CHARGE.....................88
STANDARD PROCEDURE - REFRIGERANT
SYSTEM EVACUATE...................89
STANDARD PROCEDURE - REFRIGERANT
RECOVERY..........................89
REFRIGERANT OIL
DESCRIPTION.........................90
OPERATION...........................90
STANDARD PROCEDURE - REFRIGERANT
OIL LEVEL...........................90
SUCTION LINE
REMOVAL.............................90
INSTALLATION.........................91
SERVICE PORTS
REMOVAL.............................92
INSTALLATION.........................93
24 - 60 PLUMBING - FRONTRS
ProCarManuals.com

PLUMBING - FRONT
WARNING
WARNING
WARNING:: THE ENGINE COOLING SYSTEM IS
DESIGNED TO DEVELOP INTERNAL PRESSURES
OF 97 TO 123 KILOPASCALS (14 TO 18 POUNDS
PER SQUARE INCH). DO NOT REMOVE OR
LOOSEN THE COOLANT PRESSURE CAP, CYLIN-
DER BLOCK DRAIN PLUGS, RADIATOR DRAIN,
RADIATOR HOSES, HEATER HOSES, OR HOSE
CLAMPS WHILE THE SYSTEM IS HOT AND UNDER
PRESSURE. FAILURE TO OBSERVE THIS WARNING
CAN RESULT IN SERIOUS BURNS FROM THE
HEATED ENGINE COOLANT. ALLOW THE VEHICLE
TO COOL FOR A MINIMUM OF 15 MINUTES
BEFORE OPENING THE COOLING SYSTEM FOR
SERVICE.
WARNING: THE ENGINE COOLING SYSTEM CON-
TAINS ANTIFREEZE. ANTIFREEZE IS AN ETHYLENE
GLYCOL BASED COOLANT AND IS HARMFUL IF
SWALLOWED OR IF THE VAPORS ARE INHALED. IF
SWALLOWED, DRINK TWO GLASSES OF WATER
AND INDUCE VOMITING. IF VAPORS ARE INHALED,
MOVE TO AN AREA FOR FRESH AIR. SEEK MEDI-
CAL ATTENTION IMMEDIATELY. DO NOT STORE IN
OPEN OR UNMARKED CONTAINERS. WASH SKIN
AND CLOTHING THOROUGHLY AFTER COMING IN
CONTACT WITH ETHYLENE GLYCOL. KEEP OUT
OF REACH OF CHILDREN.
WARNING: DISPOSE OF ETHYLENE GLYCOL
BASED COOLANT PROPERLY. CONTACT YOUR
DEALER OR A LOCAL GOVERNMENT AGENCY FOR
THE LOCATION OF AN APPROVED ETHYLENE GLY-
COL COLLECTION AND/OR RECYCLING CENTER IN
YOUR AREA.
WARNING - A/C PLUMBING
WARNING:: THE AIR CONDITIONING SYSTEM CON-
TAINS REFRIGERANT UNDER HIGH PRESSURE.
SEVERE PERSONAL INJURY MAY RESULT FROM
IMPROPER SERVICE PROCEDURES. REPAIRS
SHOULD ONLY BE PERFORMED BY QUALIFIED
SERVICE PERSONNEL.
WARNING: AVOID BREATHING THE REFRIGERANT
AND REFRIGERANT OIL VAPOR OR MIST. EXPO-
SURE MAY IRRITATE THE EYES, NOSE, AND/ORTHROAT. WEAR EYE PROTECTION WHEN SERVIC-
ING THE AIR CONDITIONING REFRIGERANT SYS-
TEM. SERIOUS EYE INJURY CAN RESULT FROM
DIRECT CONTACT WITH THE REFRIGERANT. IF
EYE CONTACT OCCURS, SEEK MEDICAL ATTEN-
TION IMMEDIATELY.
WARNING: DO NOT EXPOSE THE REFRIGERANT
TO OPEN FLAME. POISONOUS GAS IS CREATED
WHEN REFRIGERANT IS BURNED. AN ELEC-
TRONIC LEAK DETECTOR IS RECOMMENDED.
WARNING: IF ACCIDENTAL SYSTEM DISCHARGE
OCCURS, VENTILATE THE WORK AREA BEFORE
RESUMING SERVICE. LARGE AMOUNTS OF
REFRIGERANT RELEASED IN A CLOSED WORK
AREA WILL DISPLACE THE OXYGEN AND CAUSE
SUFFOCATION.
WARNING: THE EVAPORATION RATE OF R-134a
REFRIGERANT AT AVERAGE TEMPERATURE AND
ALTITUDE IS EXTREMELY HIGH. AS A RESULT,
ANYTHING THAT COMES IN CONTACT WITH THE
REFRIGERANT WILL FREEZE. ALWAYS PROTECT
THE SKIN OR DELICATE OBJECTS FROM DIRECT
CONTACT WITH THE REFRIGERANT.
WARNING: THE R-134a SERVICE EQUIPMENT OR
THE VEHICLE REFRIGERANT SYSTEM SHOULD
NOT BE PRESSURE TESTED OR LEAK TESTED
WITH COMPRESSED AIR. SOME MIXTURES OF AIR
AND R-134a HAVE BEEN SHOWN TO BE COMBUS-
TIBLE AT ELEVATED PRESSURES. THESE MIX-
TURES ARE POTENTIALLY DANGEROUS, AND MAY
RESULT IN FIRE OR EXPLOSION CAUSING INJURY
OR PROPERTY DAMAGE.
CAUTION - A/C PLUMBING
CAUTION:: Liquid refrigerant is corrosive to metal
surfaces. Follow the operating instructions supplied
with the service equipment being used.
CAUTION: Never add R-12 to a refrigerant system
designed to use R-134a. Damage to the system will
result.
CAUTION: R-12 refrigerant oil must not be mixed
with R-134a refrigerant oil. They are not compatible.
RSPLUMBING - FRONT24-61
ProCarManuals.com

(9) Remove the nut that secures the discharge line
fitting to the top of the compressor (Fig. 8).
(10) Disconnect the discharge line fitting from the
compressor discharge port.
(11) Remove the seals from the discharge line fit-
ting and discard.
(12) Install plugs in, or tape over the opened dis-
charge line fitting and the compressor discharge port.
(13) Remove the discharge line from the engine
compartment.
INSTALLATION
(1) Position the discharge line into the engine com-
partment.
(2) Remove the tape or plugs from the compressor
discharge port and the discharge line fitting.
(3) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the discharge line fit-
ting.
(4) Install a new dual plane seal and reconnect the
discharge line fitting to the compressor discharge
port on the top of the compressor.
(5) Install and tighten the nut that secures the
discharge line fitting to the compressor. Tighten the
nut to 23 N´m (17 ft. lbs.).
(6) Remove the tape or plugs from the condenser
inlet port and the discharge line fitting.
(7) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the discharge line fit-
ting.
(8) Install a new dual plane seal and reconnect the
discharge line fitting to the condenser inlet port on
the right side of the cooling module.
(9) Install and tighten the nut that secures the
discharge line fitting to the condenser. Tighten the
nut to 23 N´m (17 ft. lbs.).
(10) Position the radiator sight shield onto the
radiator closure panel crossmember.
(11) Install and tighten the five small screws that
secure the front fascia grille inserts to the radiator
sight shield. Tighten the screws to 2 N´m (18 in. lbs.).
(12) Install and tighten the two large screws that
secure the front fascia and the outboard ends of the
radiator sight shield to the radiator closure panel
crossmember. Tighten the screws to 6 N´m (53 in.
lbs.).
(13) Evacuate the refrigerant system. (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(14) Charge the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
EVAPORATOR
DESCRIPTION
The evaporator is located in the heater-A/C unit
housing, behind the instrument panel. The evapora-
tor is positioned in the heater-A/C housing so that all
air that enters the housing must pass over the fins of
the evaporator before it is distributed through the
system ducts and outlets. However, air passing over
the evaporator fins will only be conditioned when the
compressor is engaged and circulating refrigerant
Fig. 7 Condenser Connections
1 - CONDENSER
2 - DISCHARGE LINE FITTING
3 - LIQUID LINE FITTING
4 - NUT
Fig. 8 Discharge Line
1 - DISCHARGE LINE
2 - NUT
3 - DISCHARGE LINE FITTING
4 - STUD
5 - DISCHARGE PORT
RSPLUMBING - FRONT24-69
DISCHARGE LINE (Continued)
ProCarManuals.com

through the evaporator tubes. The heater-A/C unit
housing must be removed from the vehicle to access
the evaporator for service. The evaporator cannot be
adjusted or repaired and, if faulty or damaged, it
must be replaced.
OPERATION
Refrigerant enters the evaporator from the expan-
sion valve as a low-temperature, low-pressure liquid/
vapor mixture. As air flows over the fins of the evap-
orator, the humidity in the air condenses on the fins,
and the heat from the air is absorbed by the refrig-
erant. Heat absorption causes the refrigerant to boil
and vaporize. The refrigerant becomes a low-pressure
gas when it leaves the evaporator.
REMOVAL
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - A/C PLUMBING),
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - CAUTION - A/C PLUMBING),
and (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - HEATER PLUMB-
ING).
(1) Remove the HVAC unit housing from the vehi-
cle. (Refer to 24 - HEATING & AIR CONDITION-
ING/DISTRIBUTION - FRONT/HVAC HOUSING -
REMOVAL).
(2) Remove the heater core tubes from the heater
core. (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - FRONT/HEATER CORE -
REMOVAL - HEATER CORE TUBES).
(3) Remove and discard the foam seal from the
HVAC housing seal flange around the fresh air inlet
opening and the expansion valve/evaporator tube
opening on the dash panel side of the unit.
(4) Remove the expansion valve from the evapora-
tor inlet and outlet tube fittings. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/EXPANSION VALVE - REMOVAL).
(5) Disconnect the HVAC wire harness connector
for the blower motor from the motor connector recep-
tacle on the bottom of the outboard end of the evap-
orator housing.
(6) Disengage the HVAC wire harness from the
routing clips molded into the outside of the HVAC
housing components.
(7) Remove the four screws from the dash panel
side of the unit that secure the top of the distribution
housing to the inboard end of the evaporator housing
(Fig. 9).(8) Pull the top of the distribution housing away
from the evaporator housing far enough to disengage
the two hook formations on the bottom of the distri-
bution housing from the two receptacles on the evap-
orator housing (Fig. 10).
(9) Remove the two screws that secure the upper
intake air housing to the lower intake air housing.
(10) Remove the three screws that secure the
upper intake air housing to the top of the outboard
end of the evaporator housing. Be certain not to miss
the screw located just inside the inboard side of the
fresh air intake opening.
(11) Remove the upper intake air housing from the
top of the evaporator housing to expose the recircu-
Fig. 9 HVAC Housing
1 - DISTRIBUTION HOUSING
2 - SCREWS (3)
3 - HVAC WIRING HARNESS
4 - ROUTING CLIP
5 - EVAPORATOR HOUSING
Fig. 10 Distribution Housing Hooks
1 - RECEPTACLES ON EVAPORATOR HOUSING
2 - HOOKS ON DISTRIBUTION HOUSING
24 - 70 PLUMBING - FRONTRS
EVAPORATOR (Continued)
ProCarManuals.com

the notched area between the upper and lower hous-
ing halves.
(3) Install and tighten the twelve screws around
the perimeter of the evaporator housing that secure
the upper housing half to the lower half. Tighten the
screws to 2 N´m (18 in. lbs.).
(4) Position the upper half of the recirculation air
door onto the lower half of the door.
(5) Install and tighten the two screws that secure
the upper half of the recirculation air door to the
lower half of the door. Tighten the screws to 2 N´m
(18 in. lbs.).
(6) Position the upper intake air housing onto the
top of the evaporator housing over the recirculation
air door and the blower wheel housing. Be certain
that the upper pivot of the recirculation air door is
captured in the pivot receptacle of the upper intake
air housing.
(7) Install and tighten the three screws that secure
the upper intake air housing to the top of the out-
board end of the evaporator housing. Be certain not
to miss the screw located just inside the inboard side
of the fresh air intake opening. Tighten the screws to
2 N´m (18 in. lbs.).
(8) Install and tighten the two screws that secure
the upper intake air housing to the lower intake air
housing. Tighten the screws to 2 N´m (18 in. lbs.).
(9) Engage the two hook formations on the bottom
of the distribution housing in the two receptacles on
the evaporator housing.
(10) Roll the top of the distribution housing up
into position against the evaporator housing.
(11) Install and tighten the three screws from the
dash panel side of the unit that secure the top of the
distribution housing to the inboard end of the evapo-
rator housing. Tighten the screws to 2 N´m (18 in.
lbs.).
(12) Engage the HVAC wire harness in the routing
clips molded into the outside of the HVAC housing
components.
(13) Reconnect the HVAC wire harness connector
for the blower motor with the motor connector recep-
tacle on the bottom of the outboard end of the evap-
orator housing.
(14) Reinstall the expansion valve onto the evapo-
rator inlet and outlet tube fittings. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/EXPANSION VALVE - INSTALLATION).
(15) Install a new foam seal onto the HVAC hous-
ing seal flange around the fresh air inlet opening and
the expansion valve/evaporator tube opening on the
dash panel side of the unit.
(16) Reinstall the heater core tubes into the heater
core. (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - FRONT/HEATER CORE -
INSTALLATION - HEATER CORE TUBES).(17) Reinstall the HVAC unit housing into the
vehicle. (Refer to 24 - HEATING & AIR CONDI-
TIONING/DISTRIBUTION - FRONT/HVAC HOUS-
ING - INSTALLATION).
(18) Run the HVAC Control Actuator Calibration
procedure(Refer to 24 - HEATING & AIR CONDI-
TIONING - DIAGNOSIS AND TESTING)(Refer to 24
- HEATING & AIR CONDITIONING - DIAGNOSIS
AND TESTING).
EXPANSION VALVE
DESCRIPTION
The front ªHº valve-type thermal expansion valve
(TXV) is located at the dash panel between the liquid
and suction lines, and the evaporator coil. The
assembly consists of an H-valve body and a thermal
sensor. High-pressure, low temperature liquid refrig-
erant from the liquid line passes through the expan-
sion valve orifice, converting it into a low-pressure,
low-temperature mixture of liquid and gas before it
enters the evaporator coil. The expansion valve is a
factory calibrated unit and cannot be adjusted or
repaired. If faulty or damaged, the expansion valve
must be replaced.
OPERATION
A mechanical sensor in the expansion valve control
head monitors the temperature and pressure of the
refrigerant leaving the evaporator coil through the
suction line, and adjusts the orifice size at the liquid
line to let the proper amount of refrigerant into the
evaporator coil to meet the vehicle cooling require-
ments. Controlling the refrigerant flow through the
evaporator ensures that none of the refrigerant leav-
ing the evaporator is still in a liquid state, which
could damage the compressor. The thermo sensor
measures refrigerant suction gas temperature which
is monitored by the a/c control assembly.
DIAGNOSIS AND TESTING - EXPANSION VALVE
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - A/C PLUMBING)
and (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - CAUTION - A/C PLUMBING).
NOTE: The expansion valve should only be tested
following testing of the compressor.
24 - 72 PLUMBING - FRONTRS
EVAPORATOR (Continued)
ProCarManuals.com