2006 MERCEDES-BENZ SPRINTER ECU

(4) Remove the nut that secures the A/C liquid line
to the A/C condenser.
(5) Disconnect the A/C liquid line to the A/C con-
denser and remove and discard the O-ring seal.
(6) Install plug in, or tape over the opened liquid
line fitting and the condenser outlet port.
(7) Remove the routing clip retaining nut and dis-
engage the routing clip retainer on top of the left
frame rail from the front section of the liquid line.
(8) Remove the A/C pressure sensor from the front
liquid line fitting (Refer to 24 - HEATING & AIR
CONDITIONING/CONTROLS/A/C PRESSURE
TRANSDUCER - REMOVAL).
(9) Remove the bolt that secures the front section
of the liquid line to the top of the receiver/drier (Fig.
16).
(10) Disconnect the front section of the liquid line
from the receiver/drier and remove and discard the
O-ring seal.
(11) Install plug in, or tape over the opened liquid
line fitting and the receiver/drier inlet port.
(12) Remove the front section of the A/C liquid line
from the engine compartment.
REAR SECTION
(1) Recover the refrigerant from the refrigerant
system (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING/REFRIGERANT - STANDARD
PROCEDURE - REFRIGERANT SYSTEM RECOV-
ERY).
(2) Disconnect and isolate the negative battery
cable.
(3) Remove the grille (Refer to 23 - BODY/EXTE-
RIOR/GRILLE - REMOVAL).(4) Remove the nut that secures the A/C suction
and liquid lines to the stud on the A/C expansion
valve (Fig. 17).
(5) Disconnect the A/C suction and liquid lines
from the A/C expansion valve and remove and dis-
card the O-ring seals.
(6) Disengage the routing clip retainer from the
rear section of the A/C liquid line.
(7) Remove the bolt that secures the rear section
of the liquid line to the top of the receiver/drier (Fig.
16).
(8) Disconnect the rear section of the liquid line
from the receiver/drier.
(9) Remove the seal from the liquid line fitting
outlet port and discard.
(10) Install plugs in, or tape over the opened liquid
and suction line fittings, both receiver/drier ports and
both expansion valve ports.
(11) Remove the rear section of the liquid line from
the engine compartment.
Fig. 16 Receiver-Drier
1 - RECEIVER/DRIER
2 - A/C LIQUID LINE (REAR SECTION)
3 - A/C PRESSURE TRANSDUCER
4 - A/C LIQUID LINE (FRONT SECTION)
5 - CLAMP
Fig. 17 A/C Expansion Valve
1 - EVAPORATOR TUBE TAPPING PLATE
2 - O-RING SEAL (2)
3 - A/C EXPANSION VALVE
4 - BOLT (2)
5 - A/C SUCTION LINE
6 - NUT
7 - A/C LIQUID LINE
8 - O-RING SEAL (2)
24 - 78 PLUMBINGVA

INSTALLATION
NOTE: The A/C liquid line is serviced in two sec-
tions. The front section connects between the A/C
condenser and the receiver/drier and includes the
high side service port and the A/C pressure trans-
ducer on the fitting for the receiver/drier. The rear
section connects between the receiver/drier and the
A/C expansion valve.
FRONT SECTION
(1) Position the front section of the A/C liquid line
into the engine compartment.
(2) Remove the tape or plugs from the liquid line
fitting and the receiver/drier inlet port.
(3) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(4) Connect the front section of the liquid line to
the receiver/drier.
(5) Install the bolt that secures the liquid line fit-
ting to the receiver/drier. Tighten the bolt to 7 N´m
(62 in. lbs.).
(6) Position the front section of the liquid line into
the routing clip and install the routing clip onto the
body stud on the left frame rail.
(7) Install the routing clip retaining nut. Tighten
the nut to 5 N´m (45 in. lbs.).
(8) Remove the tape or plugs from the condenser
outlet port and the liquid line fitting.
(9) Lubricate a new O-ring seal with clean refrig-
erant oil and install it on the liquid line fitting.
(10) Connect the liquid line fitting to the con-
denser outlet port on the right side of the condenser.
(11) Install the nut that secures the liquid line fit-
ting to the condenser. Tighten the nut to 17 N´m (12
ft. lbs.).
(12) Reinstall the A/C pressure transducer (Refer
to 24 - HEATING & AIR CONDITIONING/CON-
TROLS/A/C PRESSURE TRANSDUCER - INSTAL-
LATION).
(13) Install the grille (Refer to 23 - BODY/EXTE-
RIOR/GRILLE - INSTALLATION).
(14) Reconnect the battery negative cable.
(15) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/RE-
FRIGERANT - STANDARD PROCEDURE -
REFRIGERANT SYSTEM EVACUATE).
(16) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/RE-
FRIGERANT - STANDARD PROCEDURE -
REFRIGERANT SYSTEM CHARGE).
REAR SECTION
(1) Position the rear section of the A/C liquid line
into the engine compartment.(2) Remove the tape or plugs from the liquid and
suction line fittings, the receiver/drier outlet port and
both expansion valve ports.
(3) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them onto the suction and
liquid line fittings for the expansion valve.
(4) Connect the liquid line and suction line fittings
to the A/C expansion valve.
(5) Install the nut that secures the suction line
and liquid line fittings to the stud on the A/C expan-
sion valve. Tighten the nut to 10 N´m (89 in. lbs.).
(6) Lubricate new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(7) Connect the liquid line fitting to the receiver/
drier outlet port.
(8) Install the bolt that secures the liquid line fit-
ting to the receiver/drier. Tighten the bolt to 7 N´m
(62 in. lbs.).
(9) Install the routing clip retainer to the rear sec-
tion of the liquid line.
(10) Install the grille (Refer to 23 - BODY/EXTE-
RIOR/GRILLE - INSTALLATION).
(11) Reconnect the negative battery cable.
(12) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/RE-
FRIGERANT - STANDARD PROCEDURE -
REFRIGERANT SYSTEM EVACUATE).
(13) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/RE-
FRIGERANT - STANDARD PROCEDURE -
REFRIGERANT SYSTEM CHARGE).
RECEIVER / DRIER
DESCRIPTION
The receiver/drier is mounted in a bracket secured
to the left front strut tower in the engine compart-
ment. The receiver/drier is connected between the
front and rear sections of the A/C liquid line between
the condenser outlet and the evaporator inlet.
The receiver/drier cannot be repaired. If the receiv-
er/drier is faulty or damaged, or if the refrigerant
system has been contaminated or left open to the
atmosphere for an indeterminable period or if the
compressor has failed, it must be replaced.
OPERATION
The receiver/drier performs a filtering action to
prevent foreign material in the refrigerant from con-
taminating the A/C expansion valve. Refrigerant
enters the receiver/drier as a high-pressure, low tem-
perature liquid. Desiccant inside the receiver/drier
absorbs any moisture which may have entered and
become trapped within the refrigerant system. In
addition, during periods of high demand operation of
the A/C system, the receiver/drier acts as a reservoir
to store surplus refrigerant.
VAPLUMBING 24 - 79

The receiver/drier cannot be repaired. If the receiv-
er/drier is faulty or damaged, or if an internal failure
of the A/C compressor has occurred, the receiver/drier
must be replaced.
REMOVAL
WARNING: Refer to the applicable warnings and
cautions for this system before performing the fol-
lowing operation (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - WARNINGS) and (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
CAUTIONS). Failure to follow the warnings and cau-
tions could result in possible personal injury or
death.
(1) Recover the refrigerant from the refrigerant
system (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - STANDARD PROCEDURE -
REFRIGERANT SYSTEM RECOVERY).
(2) Remove the bolts that secure the front and rear
sections of the A/C liquid line to the top of the receiv-
er/drier (Fig. 18).
(3) Disconnect the liquid line fittings from the
receiver/drier and remove and discard the O-ring
seals.
(4) Install a plug in, or tape over the opened liquid
line fittings and the receiver/drier ports.
(5) Loosen the clamp that secures the receiver/
drier to the mounting bracket.
(6) Remove the receiver/drier from the engine com-
partment.
INSTALLATION
NOTE: If the receiver/drier is being replaced, add 30
milliliters (1 fluid ounce) of refrigerant oil to the
refrigerant system. Use only refrigerant oil of the
type recommended for the A/C compressor in the
vehicle.
(1) Position the receiver/drier onto the mounting
bracket on the front left strut tower.
(2) Tighten the clamp that secures the receiver/
drier to the mounting bracket.
(3) Remove the tape or plugs from the liquid line
fittings and the receiver/drier ports.
(4) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the liquid line fit-
tings.
(5) Connect the front and rear sections of the liq-
uid line to the receiver/drier.
(6) Install the bolts that secures the liquid line fit-
tings to the receiver/drier. Tighten the bolts to 7 N´m
(62 in. lbs.).
(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).
REFRIGERANT
DESCRIPTION
The refrigerant used in this air conditioning sys-
tem is a HydroFluoroCarbon (HFC), type R-134a.
Unlike R-12, which is a ChloroFluoroCarbon (CFC),
R-134a refrigerant does not contain ozone-depleting
chlorine. R-134a refrigerant is a non-toxic, non-flam-
mable, clear, and colorless liquefied gas.
Even though R-134a does not contain chlorine, it
must be reclaimed and recycled just like CFC-type
refrigerants. This is because R-134a is a greenhouse
gas and can contribute to global warming.
OPERATION
R-134a refrigerant is not compatible with R-12
refrigerant in an air conditioning system. Even a
small amount of R-12 added to an R-134a refrigerant
system will cause compressor failure, refrigerant oil
sludge or poor air conditioning system performance.
In addition, the PolyAlkylene Glycol (PAG) synthetic
refrigerant oils used in an R-134a refrigerant system
are not compatible with the mineral-based refriger-
ant oils used in an R-12 refrigerant system.
R-134a refrigerant system service ports, service
tool couplers and refrigerant dispensing bottles have
Fig. 18 Receiver/Drier
1 - RECEIVER/DRIER
2 - A/C LIQUID LINE (REAR SECTION)
3 - A/C PRESSURE TRANSDUCER
4 - A/C LIQUID LINE (FRONT SECTION)
5 - CLAMP
24 - 80 PLUMBINGVA

all been designed with unique fittings to ensure that
an R-134a system is not accidentally contaminated
with the wrong refrigerant (R-12). There are also
labels posted in the engine compartment of the vehi-
cle and on the compressor identifying to service tech-
nicians that the air conditioning system is equipped
with R-134a.
REFRIGERANT OIL
DESCRIPTION
The refrigerant oil used in R-134a refrigerant sys-
tems is a synthetic-based, PolyAlkylene Glycol (PAG),
wax-free lubricant. Mineral-based R-12 refrigerant
oils are not compatible with PAG oils, and should
never be introduced to an R-134a refrigerant system.
There are different PAG oils available, and each
contains a different additive package. The A/C com-
pressors for this vehicle are designed to use an ND-8
PAG refrigerant oil. Use only the refrigerant oil of
this type to service the refrigerant system.
OPERATION
After performing any refrigerant recovery or recy-
cling operation, always replenish the refrigerant sys-
tem with the same amount of the recommended
refrigerant oil as was removed. Too little refrigerant
oil can cause compressor damage, and too much can
reduce air conditioning system performance.
PAG refrigerant oil is much more hygroscopic than
mineral oil, and will absorb any moisture it comes
into contact with, even moisture in the air. The PAG
oil container should always be kept tightly capped
until it is ready to be used. After use, recap the oil
container immediately to prevent moisture contami-
nation.
STANDARD PROCEDURE
REFRIGERANT OIL LEVEL
When an A/C system is assembled at the factory,
all components except the compressor are refrigerant
oil free. After the refrigerant system has been
charged and operated, the refrigerant oil in the com-
pressor is dispersed throughout the refrigerant sys-
tem. The receiver-drier, evaporator, condenser, and
compressor will each retain a significant amount of
the needed refrigerant oil.
It is important to have the correct amount of oil in
the refrigerant system. This ensures proper lubrica-
tion of the A/C compressor. Too little oil will result in
damage to the A/C compressor. Too much oil will
reduce the cooling capacity of the A/C system.
It will not be necessary to check the oil level in the
A/C compressor or to add oil, unless there has been
an oil loss. An oil loss may occur due to a rupture orleak from a refrigerant line, a connector fitting, a
component, or a component seal. If a leak occurs, add
30 milliliters (1 fluid ounce) of refrigerant oil to the
refrigerant system after the repair has been made.
Refrigerant oil loss will be evident at the leak point
by the presence of a wet, shiny surface around the
leak.
Refrigerant oil must be added when a receiver/
drier, A/C evaporator, or A/C condenser are replaced.
See the Refrigerant Oil Capacities chart. When an
A/C compressor is replaced, the refrigerant oil must
be drained from the old compressor and measured.
Drain all of the refrigerant oil from the new compres-
sor, then fill the new compressor with the same
amount of refrigerant oil that was drained out of the
old compressor.
REFRIGERANT OIL CAPACITIES
Component ml fl oz
Total A/C System Fill 410 13.9
Receiver/Drier 30 1.0
A/C Condenser 30 1.0
A/C Evaporator 60 2.0
A/C CompressorDrain and measure the oil
from the old compressor -
see text.
SUCTION LINE
REMOVAL
WARNING: Refer to the applicable warnings and
cautions for this system before performing the fol-
lowing operation (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - WARNINGS) and (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
CAUTIONS). Failure to follow the warnings and cau-
tions could result in possible personal injury or
death.
(1) Recover the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM RECOVERY)
(2) Disconnect and isolate the negative battery
cable.
(3) Remove the routing clip retaining nut and dis-
engage the metal routing clip from the A/C suction
line.
(4) Disengage the plastic routing clip located near
the A/C expansion valve from the A/C suction line.
(5) Remove the nut that secures the A/C suction
and liquid lines to the stud on the A/C expansion
valve (Fig. 19).
VAPLUMBING 24 - 81

(6) Disconnect the A/C suction and liquid lines
from the A/C expansion valve and remove and dis-
card the O-ring seals.
(7) Install plugs in, or tape over the opened liquid
and suction line fittings and both expansion valve
ports.
(8) Remove the bolt that secures the A/C suction
line to the A/C compressor (Fig. 20).
(9) Disconnect the A/C suction line from the A/C
compressor and remove and discard the O-ring seal.
(10) Install plugs in, or tape over the opened suc-
tion line fitting and the compressor suction port.
(11) Remove the A/C suction line from the engine
compartment.
INSTALLATION
(1) Position the A/C suction line into the engine
compartment.
(2) Remove plugs or tape from the suction line fit-
ting and the compressor suction port.
(3) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it onto the suction line fit-
ting.
(4) Connect the A/C suction line to the A/C com-
pressor.
(5) Install the bolt that secures the A/C suction
line to the A/C compressor. Tighten the bolt to 23
N´m (17 ft. lbs.).
(6) Remove the tape or plugs from the liquid and
suction line fittings and both expansion valve ports.
(7) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the liquid and suc-
tion line fittings.
(8) Connect the A/C liquid and suction lines to the
A/C expansion valve.
(9) Install the nut that secures the A/C liquid and
suction lines to the A/C expansion valve. Tighten the
nut to 10 N´m (89 in. lbs.).
(10) Position the metal routing clip around the A/C
suction line and install the routing clip onto the body
stud.
(11) Install the routing clip retaining nut. Tighten
the nut to 5 N´m (45 in. lbs.).
Fig. 19 A/C Expansion Valve
1 - EVAPORATOR TUBE TAPPING PLATE
2 - O-RING SEAL (2)
3 - A/C EXPANSION VALVE
4 - BOLT (2)
5 - A/C SUCTION LINE
6 - NUT
7 - A/C LIQUID LINE
8 - O-RING SEAL (2)
Fig. 20 A/C Compressor - Refrigerant Lines
1 - A/C COMPRESSOR
2 - O-RING SEAL
3 - A/C SUCTION LINE
4 - BOLT
5 - RETAINING CLIP
6 - BOLT
7 - A/C DISCHARGE LINE
8 - O-RING SEAL
24 - 82 PLUMBINGVA

(12) Install the plastic routing clip retainer onto
the A/C suction line.
(13) Reconnect the negative battery cable.
(14) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM EVACUATE).
(15) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM CHARGE).
WATER VALVE
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Partially drain the engine cooling system
(Refer to 7 - COOLING/ENGINE/COOLANT - STAN-
DARD PROCEDURE - DRAINING COOLING SYS-
TEM).
(3) Disconnect the wire harness connector from the
heater water valve (Fig. 21).
(4) Loosen the hose clamps from the heater water
valve.
(5) Using a twisting motion gently remove the
heater hoses from the heater water valve.
(6) Remove the bolts that secure the heater water
valve bracket.
(7) Remove the bracket and pulsed water control
valve from the engine compartment.
(8) Turn the bracket slightly and remove the water
valve from the rubber mounts.
(9) If necessary, remove the rubber mounts from
the bracket or water valve.
INSTALLATION
(1) If removed, install the rubber mounts to the
heater water valve or bracket.
(2) Turn bracket slightly to the right and install
the heater water valve to the bracket.
(3) Install the water valve and mounting bracket
into the engine compartment.
(4) Install the two bracket retaining bolts. Tighten
the bolts to 5 N´m (45 in. lbs.).
(5) Using a twisting motion gently install the
heater hoses onto the water valve.
(6) Tighten the hose clamps securely.
(7) Connect the wire harness connector to the
heater water valve.
(8) Reconnect the negative battery cable.
(9) Fill the engine cooling system (Refer to 7 -
COOLING/ENGINE/COOLANT - STANDARD PRO-
CEDURE - COOLING SYSTEM FILL).
REARA/CCONDENSER FAN
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the cover from the rear A/C condenser
housing (Refer to 24 - HEATING & AIR CONDI-
TIONING/DISTRIBUTION - REAR/A/C CON-
DENSER COVER - REMOVAL).
Fig. 21 Heater Water Valve
1 - HEATER WATER VALVE
2 - HOSE CLAMP (3)
3 - HEATER HOSE (3)
4 - RUBBER MOUNT (2)
5 - BOLTS (2)
6 - BRACKET
7 - RUBBER MOUNT
VAPLUMBING 24 - 83

(3) Disconnect the condenser fan wire harness
from the condenser fan suppression filter (Fig. 22).
(4) Loosen the four bolts that secure the rear A/C
condenser fan to the top of the rear A/C condenser
housing.
(5) Rotate the rear A/C condenser fan counter-
clockwise and remove the fan from the top of the rear
A/C condenser housing.
INSTALLATION
(1) Position the rear A/C condenser fan to the top
of the rear A/C condenser housing.
(2) Rotate the rear A/C condenser fan clockwise to
engage the fan to the four retaining bolts. Tighten
the bolts to 12 N´m (106 in. lbs.).
(3) Connect the condenser fan wire harness to the
rear condenser fan suppression filter.
(4) Reconnect the negative battery cable.
(5) Install the cover onto the rear A/C condenser
housing (Refer to 24 - HEATING & AIR CONDI-
TIONING/DISTRIBUTION - REAR/A/C CON-
DENSER COVER - INSTALLATION).
REARA/CEVAPORATOR
REMOVAL
WARNING: Refer to the applicable warnings and
cautions for this system before performing the fol-
lowing operation (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - WARNINGS) and (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
CAUTIONS). Failure to follow the warnings and cau-tions could result in possible personal injury or
death.
(1) Remove the rear A/C evaporator housing and
place it on a workbench (Refer to 24 - HEATING &
AIR CONDITIONING/DISTRIBUTION - REAR/
REAR A/C EVAPORATOR HOUSING - REMOVAL).
(2) Remove the five screws and washers that
secure the condensate drain pan to the bottom of the
rear A/C evaporator and remove the drain pan (Fig.
23).
(3) Remove the insulating tape from around the
area of the rear A/C expansion valve and disconnect
the expansion valve from the rear A/C evaporator
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING/REAR A/C EXPANSION VALVE -
REMOVAL).
(4) Remove the left blower motor from the rear
A/C evaporator housing (Refer to 24 - HEATING &
AIR CONDITIONING/DISTRIBUTION - REAR/
BLOWER MOTOR - REMOVAL).
CAUTION: Be careful when drilling out rivets to pre-
vent damage to the rear A/C components.
(5) Remove the rivets that secure the three covers
to the rear A/C evaporator and remove the covers.
(6) Remove the four rivets that secure the rear A/C
evaporator the bottom of the rear A/C evaporator
housing and remove the evaporator.
Fig. 22 Rear A/C Condenser Fan
1 - REAR A/C CONDENSER FAN
2 - BOLT (4)
3 - REAR CONDENSER FAN SUPPRESSION FILTER
4 - FAN WIRE HARNESS CONNECTOR
5 - REAR A/C CONDENSER HOUSING
Fig. 23 Rear A/C Evaporator
1 - REAR A/C EVAPORATOR HOUSING
2 - RIVET (12)
3 - COVERS
4 - REAR A/;C EVAPORATOR
5 - SCREW AND WASHER (5)
6 - CONDENSATE DRAIN PAN
24 - 84 PLUMBINGVA

INSTALLATION
NOTE: Be certain to add refrigerant oil if the rear
A/C evaporator is being replaced. The refrigerant oil
must be drained from the old evaporator and mea-
sured to determine the amount of refrigerant oil to
add to the new evaporator. Use only refrigerant oil
of the type recommended for the rear A/C compres-
sor in the vehicle.
(1) If the rear A/C evaporator is being replaced,
install the correct amount and type of refrigerant oil
into the new rear A/C evaporator. Drain the old evap-
orator and measure the refrigerant oil. Fill the new
evaporator with the same amount of new refrigerant
oil that was drained out of the old evaporator.
(2) Position the rear A/C evaporator to the bottom
of the rear A/C evaporator housing and install four
new rivets.
(3) Position the three covers to the rear A/C evap-
orator and install eight new rivets.
(4) Install the left blower motor onto the rear A/C
evaporator housing (Refer to 24 - HEATING & AIR
CONDITIONING/DISTRIBUTION - REAR/BLOWER
MOTOR - INSTALLATION).
(5) Connect the rear A/C expansion valve to the
rear A/C evaporator and install new insulating tape
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING/REAR A/C EXPANSION VALVE -
INSTALLATION).
(6) Position the condensate drain pan to the bot-
tom of the rear A/C evaporator and install the five
screws and washers that secure the drain pan to the
evaporator. Tighten the screws to 2.2 N´m (20 in.
lbs.).
(7) Install the rear A/C evaporator housing (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/REAR A/C EVAPORATOR HOUSING -
INSTALLATION).
REARA/CEXPANSION VALVE
DESCRIPTION
The rear A/C expansion valve controls the amount
of refrigerant entering the rear A/C evaporator (Fig.
24). The rear A/C expansion valve is of an externally-
equalized thermostatic expansion valve (TXV) design
and consists of a cast metal body with a removable
equalizer tube and an integral thermal sensor which
uses a capillary tube and sensing bulb.
The rear A/C expansion valve is located to the left
of the rear blower motors in the rear evaporator
housing.
OPERATION
High-pressure, high temperature liquid refrigerant
from the liquid line passes through the expansion
valve orifice, converting it into a low-pressure, low-
temperature mixture of liquid and gas before it
enters the A/C evaporator. A thermal sensor in the
rear A/C expansion valve monitors the temperature
of the refrigerant leaving the rear evaporator by use
of a sensing bulb positioned next to the evaporator
outlet tube. The thermal sensor adjusts the orifice
size at the evaporator inlet to allow the proper
amount of refrigerant into the rear A/C evaporator in
order to meet vehicle cooling requirements. Control-
ling the refrigerant flow through the A/C evaporator
ensures that none of the refrigerant leaving the evap-
orator is still in a liquid state, which could cause
damage to the A/C compressor.
To overcome the effect of the pressure drop within
the rear A/C evaporator, an external equalizer tube is
connected to the evaporator outlet tube and runs to
the underside if the diaphragm within the expansion
valve.
The rear A/C expansion valve is factory calibrated
and cannot be adjusted or repaired and, if faulty or
damaged, it must be replaced.
Fig. 24 Rear A/C Expansion Valve
1 - REAR A/C EXPANSION VALVE
2 - EQUALIZER TUBE
3 - CAPILLARY TUBE
4 - SENSING BULB
VAPLUMBING 24 - 85