Isuzu Rodeo UE. Manual - part 23

1A–62 HEATING, VENTILATION AND AIR CONDITIONING (HVAC)

Removal

1. Disconnect the battery ground cable.
2. Discharge and recover refrigerant.

D

Refer to Refrigerant Recovery in this section.

3. Remove radiator grille.
4. Remove clip and clamp.
5. Disconnect liquid line (High-pressure pipe).
6. Disconnect suction line (Low-pressure pipe) using a

back-up wrench.

7. Disconnect suction line (Low-pressure hose) using a

back-up wrench.

8. Disconnect discharge line (High-pressure hose)

using a back-up wrench.

D

Use a backup wrench when disconnecting and
reconnecting the refrigerant lines.

D

When removing the refrigerant line connecting part,
the connecting part should immediately be plugged
or capped to prevent foreign matter from being
mixed into the line.

Installation

To install, follow the removal steps in the reverse order,
noting the following point:

1. O-rings cannot be reused. Always replace with new

ones. 

2. Be sure to apply new compressor oil to the O-rings

when connecting lines.

3. Tighten the refrigerant line to the specified torque.

Refer to Main Data and Specifications for Torque
Specifications in this section.

Main Data And Specifications

General Specifications

Heater Unit

Temperature control

Reheat air mix system

Capacity

3,700 Kcal./hr.

Air flow

280 m

#

/h

HEATER CORE

Type

Fin and tube type

Element dimension

167 mm (6.6 in.) 

×

 151 mm (5.9 in.) 

×

 35 mm (1.4 in.)

Radiating area

Approx. 2.4 m

@

EVAPORATOR ASSEMBLY

Capacity

4,100 Kcal./hr.

Air flow

430 m

#

/hr

EVAPORATOR CORE

Type

Al-laminate louver fin type

Element dimension

235 mm (9.3 in.) 

×

 224 mm (8.8 in.) 

×

 60 mm (2.4 in.)

EXPANSION VALVE

Type

External pressure equalizer type

THERMOSTAT SWITCH

Type

Electronic thermostat

OFF: Below 0.5 

±

 0.5 

°

C (32.9 

±

 0.9 

°

F)

ON: Above 4.5 

±

 0.5 

°

C (40.1 

±

 0.9 

°

F)

CONDENSER

Type

Parallel flow type

Radiation performance

9,400 Kcal./hr

RECEIVER/DRIER

Type

Assembly includes sight glass with dual (triple) pres-
sure switch (V6) or pressure sensor (L14)

Internal volume

300 cc (10 fl.oz.)

HEATING, VENTILATION AND AIR CONDITIONING (HVAC) 1A–63

PRESSURE SWITCH

Type

Dual pressure switch

Low pressure control

ON: 205.9

±

29.4 kPa (29.9

±

4.3 psi)

OFF: 176.5

±

24.5 kPa (25.6

±

3.6 psi)

High pressure control

ON: 2353.6

±

196.1 kPa (341.3

±

28.4 psi)

OFF: 2942.0

±

196.1 kPa (426.6

±

28.4 psi)

Triple pressure switch (V6, A/T)

Low pressure control

ON: 196.3

±

29.4 kPa (27.0

±

4.3 psi)

OFF: 176.5

±

19.6 kPa (25.6

±

2.8 psi)

Medium pressure control

ON: 1471.0

±

98.1 kPa (213.3

±

14.2 psi)

OFF: 1078.7

±

117.7 kPa (156.4

±

17.7 psi)

High pressure control

ON: 2353.6

±

196.1 kPa (341.3

±

28.4 psi)

OFF: 2942.0

±

196.1 kPa (426.6

±

28.4 psi)

REFRIGERANT

Type

HFC-134a

Specified amount

650 g (1.43 lbs.)

Torque Specifications

852RX003

1A–64 HEATING, VENTILATION AND AIR CONDITIONING (HVAC)

874RX006

HEATING, VENTILATION AND AIR CONDITIONING (HVAC) 1A–65

Compressor

Service Precaution

WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT LOCATION VIEW IN ORDER TO
DETERMINE WHETHER YOU ARE PERFORMING
SERVICE ON OR NEAR THE SRS COMPONENTS OR
THE SRS WIRING. WHEN YOU ARE PERFORMING
SERVICE ON OR NEAR THE SRS COMPONENTS OR
THE SRS WIRING, REFER TO THE SRS ON-VEHICLE
SERVICE INFORMATION. FAILURE TO FOLLOW
CAUTIONS COULD RESULT IN POSSIBLE AIR BAG
DEPLOYMENT, PERSONAL INJURY, OR
OTHERWISE UNNEEDED SRS SYSTEM REPAIRS.

CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners  that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (paints, greases, or other
corrosion inhibitors) on threaded fasteners or
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener. When
you install fasteners, use the correct tightening
sequence and specifications. Following these
instructions can help you avoid damage to parts and
systems.

General Description

When servicing the compressor, keep dirt or foreign
material from getting on or into the compressor parts and
system.  Clean tools and a clean work area are important
for proper service.  The compressor connections and the
outside of the compressor should be cleaned before any
”On–Vehicle” repair, or before removal of the
compressor.  The parts must be kept clean at all times and
any parts to be reassembled should be cleaned with
Trichloroethane, naphtha, kerosene, or equivalent
solvent, and dried with dry air.  Use only lint free cloths to
wipe parts.
The operations described below are based on bench
overhaul with compressor removed from the vehicle,
except as noted.  They have been prepared in order of
accessibility of the components.  When the compressor is
removed from the vehicle for servicing, the oil remaining
in the compressor should be discarded and new
compressor oil added to the compressor.
Compressor malfunction will appear in one of four ways:
noise, seizure, leakage or low discharge pressure.
Resonant compressor noises are not cause for alarm;
however, irregular noise or rattles may indicate broken
parts or excessive clearances due to wear.  To check
seizure, de–energize the magnetic clutch and check to

see if the drive plate can be rotated.  If rotation is
impossible, the compressor is seized.  Low discharge
pressure may be due to a faulty internal seal of the
compressor, or a restriction in the compressor.  Low
discharge pressure may also be due to an insufficient
refrigerant charge or a restriction elsewhere in the
system.  These possibilities should be checked prior to
servicing the compressor.  If the compressor is
inoperative, but is not seized, check to see if current is
being supplied to the magnetic clutch coil terminals.
The compressor oil used in the HFC–134a system
compressor differs from that used in R–12 systems.
Also, compressor oil to be used varies according to the
compressor model.  Be sure to avoid mixing two or more
different types of oil.
If the wrong oil is used, lubrication will be poor and the
compressor will seize or malfunction.

DKV-14G Type Compressor

DKV–14G is equipped with five–vane rotary compressor.
These vanes are built into a rotor which is mounted on a
shaft.
When the shaft rotates, the vanes built into the cylinder
block assembly are operated by centrifugal force.
This changes the volume of the spare formed by the rotor
and cylinder, resulting in the intake and compression of
the refrigerant gas.  The discharge valve and the valve
stopper, which protects the discharge valve, are built into
the cylinder block assembly.  There is no suction valve but
a shaft seal is installed between the shaft and head; a
trigger valve, which applies back pressure to the vanes, is
installed in the cylinder block and a refrigerant gas
temperature sensor is installed in the front head.
The specified quantity of compressor oil is contained in
the compressor to lubricate the various parts using the
refrigerant gas discharge pressure.

871RX002