charging ISUZU KB P190 2007 Workshop Repair Manual

1-30 HEATER AND AIR CONDITIONING
ON-VEHICLE SERVICE
PRECAUTIONS FOR REPLACEMENT OR
REPAIR OF AIR CONDITIONING PARTS
There are certain procedures, practices and precautions that
should be followed when servicing air conditioning systems:
• Keep your work area clean.
• Always wear safety goggle and protective gloves when
working on refrigerant systems.
• Beware of the danger of carbon monoxide fumes caused by
running the engine.
• Beware of discharged refrigerant in enclosed or improperly
ventilated garages.
•
Always disconnect the negative battery cable and discharge
and recover the refrigerant whenever repairing the air
conditioning system.
• W hen discharging and recovering the refrigerant, do not
allow refrigerant to discharge too fast; it will draw
compressor oil out of the system.
• Keep moisture and contaminants out of the system. W hen
disconnecting or removing any lines or parts, use plugs or
caps to close the fittings immediately.
Never remove the caps or plugs until the lines or parts are reconnected or installed.
• W hen disconnecting or reconnecting the lines, use two
wrenches to support the line fitting, to prevent from twisting
or other damage.
• Always install new O-rings whenever a connection is
disassembled.
• Before connecting any hoses or lines, apply new specified
compressor oil to the O-rings.
• W hen removing and replacing any parts which require
discharging the refrigerant circuit, the operations described
in this section must be performed in the following sequence:

1) Using the ACR
4 (HFC-134a Refrigerant Recovery/
Recycling/Recharging/System) or equivalent to
thoroughly discharge and recover the refrigerant.
ACR
4 (115V 60Hz) : 5-8840-0629-0 (J-39500-A)
ACR4 (220-240V 50/60Hz)
: 5-8840-0630-0 (J-39500-220A)
ACR
4 (220-240V 50/60Hz Australian model)
: 5-8840-0631-0 (J-39500-220ANZ)
2) Remove and replace the defective part.
3)
After evacuation, charge the air conditioning system and
check for leaks.


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ISUZU KB P190 2007

HEATER AND AIR CONDITIONING 1-33
RECOVERY, RECYCLING, EVACUATION
AND CHARGING
Handling Refrigerant-134a (HFC-134a)
Air conditioning systems contain HFC-134a.
This is a chemical mixture, which requires special handling
procedures to avoid personal injury.
• Always wear safety goggles and protective gloves.
• Always work in a well-ventilated area. Do not weld or steam
clean on or near any vehicle-installed air conditioning lines
or components.
• If HFC-134a should come in contact with any part of the
body, flush the exposed area with cold water and
immediately seek medical help.
• If it is necessary to transport or carry any container of HFC-
134a in a vehicle, do not carry it in the passenger
compartment.
• If it is necessary to fill a small HFC-134a container from a
large one, never fill the container completely. Space should
always be allowed above the liquid for expansion.
• Keep HFC-134a containers stored below 40 °C (104 °F).


WARNING
•
••
•
SHOULD HFC-134a CONTACT YOUR EYE(S), CONSULT
A DOCTOR IMMEDIATELY.
•
••
•
DO NOT RUB THE AFFECTED EYE(S). INSTEAD,
SPLASH QUANTITIES OF FRESH COLD WATER OVER
THE AFFECTED AREA TO GRADUALLY RAISE THE
TEMPERATURE OF THE REFRIGERANT ABOVE THE
FREEZING POINT.
•
••
•
OBTAIN PROPER MEDICAL TREATMENT AS SOON AS
POSSIBLE. SHOULD THE HFC-134a TOUCH THE SKIN,
THE INJURY MUST BE TREATED THE SAME AS SKIN
WHICH HAS BEEN FROSTBITTEN OR FROZEN.

F06R300012


REFRIGERANT RECOVERY
The refrigerant must be discharged and recovered by using
ACR4 (HFC-134a Refrigerant Recovery/Recycling/Recharging/
System) or equivalent before removing or installing air
conditioning parts.
ACR
4 (115V 60Hz) :5-8840-0629-0 (J-39500-A)
ACR4 (220-240V 50/60Hz)
: 5-8840-0630-0 (J-39500-220A)
ACR
4 (220-240V 50/60Hz Australian model)
: 5-8840-0631-0 (J-39500-220ANZ)
1) Connect the high and low charging hoses of the ACR
4 (or
equivalent) as shown.
2) Recover the refrigerant by following the ACR
4
Manufacturer's Instructions.
3) W hen a part is removed, put a cap or a plug on the connecting portion so that dust, dirt or moisture cannot get
into it.

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1-34 HEATER AND AIR CONDITIONING

REFRIGERANT RECYCLING
Recycle the refrigerant recovered by ACR4 or equivalent.
For the details of the actual operation, follow the steps in the
ACR
4 Manufacturer's Instructions.
ACR4 (115V 60Hz) :5-8840-0629-0 (J-39500-A)
ACR4 (220-240V 50/60Hz)
: 5-8840-0630-0 (J-39500-220A)
ACR
4 (220-240V 50/60Hz Australian model)
: 5-8840-0631-0 (J-39500-220ANZ)

F06R300014


EVACUATION OF THE REFRIGERANT
SYSTEM
NOTE:
Explained below is a method using a vacuum pump. Refer
to the ACR
4 (or equivalent) Manufacturer's Instructions
when evacuating the system with ACR4 (or equivalent).

Air and moisture in the refrigerant will cause problems in the air
conditioning system.
Therefore, before charging the refrigerant, be sure to evacuate
air and moisture thoroughly from the system.
1) Connect the gauge manifold. •
••
•
High-pressure valve (HI) - Discharge-side
•
••
•
Low-pressure valve (LOW ) - Suction-side
2) Discharge and recover the refrigerant.
3) Connect the center hose of the gauge manifold set to the vacuum pump inlet.
4) Operate the vacuum pump, open shutoff valve and then open both hand valves.
5) W hen the low-pressure gauge indicates approx. 100kPa (750 mmHg/30 inHg), continue the evacuation for 5 minutes
or more.
6) Close both hand valves and stop the vacuum pump.


7) Check to ensure that the pressure does not change after 10
minutes or more. •
••
•
If the pressure changes, check the system for leaks.
•
••
•
If leaks occur, retighten the refrigerant line connections
and repeat the evacuation steps.
8) If no leaks are found, again operate the vacuum pump for 20 minutes or more. After confirming that the gauge
manifold pressure is at 100 kPa (750 mmHg/30 inHg), close
both hand valves.
9) Close positive shutoff valve.
Stop the vacuum pump and disconnect the center hose from the vacuum pump.


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HEATER AND AIR CONDITIONING 1-35
CHARGING THE REFRIGERANT SYSTEM
There are various methods of charging refrigerant into the air
conditioning system.
These include using the ACR
4 (HFC-134a Refrigerant
Recovery/ Recycling/Recharging/System) or equivalent and
direct charging with a manifold gauge charging station.
ACR
4 (115V 60Hz) : 5-8840-0629-0 (J-39500-A)
ACR4 (220-240V 50/60Hz)
: 5-8840-0630-0 (J-39500-220A)
ACR
4 (220-240V 50/60Hz Australian model)
: 5-8840-0631-0 (J-39500-220ANZ)
F06R300012
Charging procedure
•
••
•
ACR4 (or equivalent) method
For the charging of refrigerant recovered by ACR4, follow the
Manufacturer's Instruction.


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1-36 HEATER AND AIR CONDITIONING
F06R300013



•
••
•
Direct charging with a manifold gauge charging
station method.
Handling the charging valve handle when installing refrigerant
container.
1) Before attaching the charge valve to the refrigerant container, turn the charge valve handle counterclockwise
until the needle is fully retracted.
2) Turn the plate nut counterclockwise until it reaches its highest position relative to the charge valve.
3) Install the charge valve onto the refrigerant container.
4) Turn the plate nut clockwise and connect the center hose of the manifold gauge to the charge valve.
5) Tighten the plate nut sufficiently by hand. Then turn the charge valve handle clockwise to lower the needle and bore
a hole in the refrigerant container.
6) Turn the charge valve handle counterclockwise to raise the needle. The refrigerant in the refrigerant container is
charged into the air conditioning system by the operation of
the manifold gauge.
•
••
•
Be absolutely sure not to reuse the emptied

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HEATER AND AIR CONDITIONING 1-37
refrigerant container.


1) Make sure the evacuation process is correctly completed.
2) Connect the center-hose of the manifold gauge to the refrigerant container. •
••
•
Turn the charge valve handle counterclockwise to purge
to the charging line and purge any air exiting in the
center-hose of the manifold gauge.
3) Open the low-pressure hand valve and charge the refrigerant about 200 g (0.44 lbs.). •
••
•
Make sure the high-pressure hand valve is closed.
•
••
•
Avoid charging the refrigerant by turning the refrigerant
container upside down.
4) Close the low-pressure hand valve of the manifold gauge. •
••
•
Check to ensure that the degree of pressure does not
change.
5) Check the refrigerant leaks by using a HFC-134a leak detector. •
••
•
If a leak occurs, repair the leak connection, and start all
over again from the first step of evacuation.
6) If no leaks are found, open the low-pressure hand valve of the manifold gauge. Then continue charging refrigerant to
the system. •
••
•
W hen charging the system becomes difficult:
(1) Run the engine at Idling and close the all vehicle doors.
(2) A/C switch is "ON".
(3) Set the fan control knob (fan switch) to its highest position.
(4) Set air source selector lever to “RECIRC”



WARNING
BE ABSOLUTELY SURE NOT TO OPEN THE HIGH-
PRESSURE HAND VALVE. SHOULD THE HIGH-
PRESSURE HAND VALVE BE OPENED, THE HIGH-
PRESSURE REFRIGERANT GAS WOULD FLOW
BACKWARD, AND THIS MAY CAUSE THE REFRIGERANT
CONTAINER TO BURST.
7) W hen the refrigerant container is emptied, use the following procedure to replace it with a new refrigerant container.
(1) Close the low-pressure hand valve.
(2) Raise the needle upward and remove the charge valve.
(3) Reinstall the charge valve to the new refrigerant container.
(4) Purge any air existing in the center hose of the manifold gauge.






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1-38 HEATER AND AIR CONDITIONING
8) Charge the system to the specified amount and then close the low-pressure hand valve.
Refrigerant Amount g(lbs)
4JA1-T, 4JH1-TC, C24SE 720 (1.59)
4JJ1-TC (Standard Output)
4JJ1-TC (High Output)
4JK1-TC (High Output)
650 (1.43)

9) Check for refrigerant leaks by using a HFC-134a leak detector.
• A fully charged system is indicated by the sight glass on
the receiver/drier being free of any bubbles (Refer to
"Reading Sight Glass").
• Check the high and low pressure value of the manifold
gauge. (Refer to “CHECKING REFRIGERANT SYSTEM
W ITH MAINFOLD GAUGE” in SERVICE
INFORMATION.)
Immediately after charging refrigerant, both high and low
pressures are slightly high and to the left of the gauge, but they
settle down to the guide pressure valves as shown below:
• Ambient temperature; 30 ∼35 °C (86 ∼95 °F)
• Guide pressure
High-pressure side;
Approx. 1373 ∼1670 kPa (14 ∼17 kg/cm
2 / 199 ∼242 psi)
Low-pressure side;
Approx. 127 ∼245 kPa (1.3 ∼2.5 kg/cm
2 / 18 ∼36 psi)
10) Close the low pressure hand valve and charge valve of the refrigerant container.
11) Stop the air conditioning and the engine.
12) Disconnect the high and low pressure hoses from the manifold gauge fittings.





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HEATER AND AIR CONDITIONING 1-51

GENERAL REPAIR PROCEDURE
OIL SPECIFICATION
•
The HFC-134a system requires a synthetic (PAG)
compressor oil.
• Compressor (PAG) oil varies according to compressor
model. Be sure to use oil specified for the model of
compressor.
Specified Compressor Oil
DH-PR



HANDLING OF OIL
•
The oil should be free from moisture, dust, metal powder,
etc.
• Do not mix with other oil.
• The water content in the oil increases when exposed to the
air. After use, seal oil from air immediately.
• The compressor oil must be stored in steel containers, not
in plastic containers.

COMPRESSOR OIL CHECK
The Oil used to lubricate the compressor is circulating with the
refrigerant.
W henever replacing any component of the system or a large
amount of gas leakage occurs, add oil to maintain the original
amount of. oil.

Oil Capacity
Capacity total in
system CR-14 180 cm
3 (5.07 lmp fl oz)
Compressor
(Service parts)
charging amount
CR-14
180 cm3 (5.07 lmp fl oz)



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1-52 HEATER AND AIR CONDITIONING
Checking and Adjusting for Used Compressor
(1) Perform Oil return operation.
(Refer to "Oil Return Operation" in this section.)
(2) Discharge refrigerant and remove the compressor.


(3) Drain the compressor oil and measure the extracted oil with
a measuring cylinder.
(4) Check the compressor oil for contamination.
(Refer to "Contamination of Compressor Oil" in this section.)
(5) Adjust oil level following the procedure below.
Type Collected Amount Charging Amount
more than 90 cm3
(2.53 lmp fl oz) same as collected
amount
less than 90 cm3
(2.53 lmp fl oz) 90 cm3
(2.53 lmp fl oz) CR-14

(6) Install the compressor, then evacuate, charge and perform
oil return operation.
(7) Check system operation.



When it is impossible to perform oil return operation, the
compressor oil should be checked in the following order:
(1) Discharge refrigerant and remove the compressor.
(2) Drain the compressor oil and measure the extracted oil with a measuring cylinder.
(3) Check the oil for contamination.
(4) If more than 90 cm
3 (2.53 lmp fl oz) for CR-14 type is
extracted from the compressor, supply same amount of oil
to the compressor to be installed.
If the amount of oil extracted is less than 90 cm
3 (2.53 lmp
fl oz) for CR-14 type recheck the compressor oil in the
following order:
(5) Supply 90 cm
3 (2.53 lmp fl oz) for CR-14 type oil to the
compressor and install it onto the vehicle.
(6) Perform oil return operation.
(7) Remove the compressor and recheck the amount of oil.
(8) Adjust the compressor oil.


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HEATER AND AIR CONDITIONING 1-89
AIR CONDITIONING CYCLE TROUBLESHOOTING

TROUBLE POSSIBLE CAUSE CORRECTION
1. Magnetic clutch does not run
•
Refer to “MAGNETIC CLUTCH”
troubleshooting in this section
2. Compressor is not rotating properly
• Drive belt loosened or broken •
Adjust the drive belt to the specified
tension or replace the drive belt
• Magnetic clutch face is not clean and
slips •
Clean the magnetic clutch face or replace

• Incorrect clearance between magnetic
drive plate and pulley •
Adjust the clearance (Refer to
“COMPRESSOR OVERHAUL”)
• Compressor oil leaks from shaft seal or
shell •
Replace the compressor

• Compressor seized • Replace the compressor
3. Insufficient or excessive charge of
refrigerant •
Discharge and recover refrigerant.
Recharge to specified amount.
4. Leaks in the refrigerant system


•
Check refrigerant system for leaks and
repair as necessary
Discharge and recover refrigerant.
Recharge to specified amount.
5. Condenser clogged or insufficient radiation

•
Clean the condenser or replace as
necessary
• Check radiator or condenser fan function
6. Temperature control link unit of the heater
unit defective •
Repair the link unit
7. Unsteady operation due to foreign
substance in expansion valve •
Replace the expansion valve

No cooling or
insufficient
cooling
8. Poor operation of electronic thermostat
•
Check electronic thermostat and replace
as necessary
1. Evaporator clogged or frosted
•
Check evaporator core and replace or
clean the core
2. Air leaking from cooling unit or air duct
•
Check evaporator and duct connection,
then repair as necessary
Insufficient
velocity
of cooling air
3. Blower motor does not rotate properly
• Refer to “FAN CONTROL KNOB (FAN
SW ITCH)” troubleshooting in this section

* For the execution of the charging and discharging operation in the table above, refer to the “RECOVERY,
RECYCLING, EVACUATING AND CHARGING” in this section.



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