DAEWOO M-150 BL2
SECTION 7B
MANUAL CONTROL HEATING, VENTILATION,
AND AIR CONDITIONING SYSTEM
CAUTION: Disconnect the negative battery cable before removing or installing any electrical unit or when a
tool or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable
will help prevent personal injury and damage to the vehicle. The ignition must also be in B unless otherwise
noted.
TABLE OF CONTENTS
Description and Operation 7B-2. . . . . . . . . . . . . . . . . .
System Components – Functional 7B-2. . . . . . . . . . .
Component Locator 7B-3. . . . . . . . . . . . . . . . . . . . . . . .
A/C System 7B-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Information and Procedures 7B-5. . . . .
General Diagnosis 7B-5. . . . . . . . . . . . . . . . . . . . . . . . . . .
Testing the Refrigerant System 7B-5. . . . . . . . . . . . . .
Insufficient Cooling “Quick Check”
Procedure 7B-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pressure-Temperature Relationship
of R-134a 7B-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Leak Testing the Refrigerant System 7B-7. . . . . . . . .
Air Conditioning System Diagnosis 7B-8. . . . . . . . . . . . .
Insufficient Cooling Diagnosis 7B-8. . . . . . . . . . . . . . .
Symptom Diagnosis 7B-11. . . . . . . . . . . . . . . . . . . . . . . .
Pressure Test Chart (R-134a System) 7B-11. . . . . . .
Repair Instructions 7B-13. . . . . . . . . . . . . . . . . . . . . . . .
On-Vehicle Service 7B-13. . . . . . . . . . . . . . . . . . . . . . . . .
General A/C System Service Procedures 7B-13. . . . . .
O-Ring Replacement 7B-13. . . . . . . . . . . . . . . . . . . . .
Handling Refrigerant 7B-13. . . . . . . . . . . . . . . . . . . . . .
Handling of Refrigerant Lines and Fittings 7B-13. . .
Maintaining Chemical Stability in the
Refrigeration System 7B-14. . . . . . . . . . . . . . . . . . .
Discharging, Adding Oil, Evacuating, and
Charging Procedures for A/C System 7B-14. . . . . Serviceable Components 7B-17. . . . . . . . . . . . . . . . . . . .
Control Assembly and Control Cables 7B-17. . . . . . .
Blower Motor and Cooling Hose 7B-17. . . . . . . . . . . .
Blower Resistor 7B-17. . . . . . . . . . . . . . . . . . . . . . . . . .
Blower Motor Switch 7B-17. . . . . . . . . . . . . . . . . . . . . .
A/C Push Knob 7B-18. . . . . . . . . . . . . . . . . . . . . . . . . .
Receiver–Dryer and Dual Cut Switch 7B-18. . . . . . . .
Receiver–Dryer Bracket 7B-20. . . . . . . . . . . . . . . . . . .
Compressor 7B-20. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Condenser 7B-21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A/C High Pressure Pipe Line 7B-22. . . . . . . . . . . . . . .
A/C Low Pressure Pipe Line 7B-25. . . . . . . . . . . . . . .
Evaporator Unit and Drain Hose 7B-26. . . . . . . . . . . .
Unit Repair 7B-28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Evaporator Core and Expansion Valve 7B-28. . . . . .
Compressor Overhaul 7B-29. . . . . . . . . . . . . . . . . . . . .
Specifications 7B-30. . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Specifications 7B-30. . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 7B-30. . . . . . . . . .
Special Tools and Equipment 7B-31. . . . . . . . . . . . . .
Special Tools Table 7B-31. . . . . . . . . . . . . . . . . . . . . . .
Schematic and Routing Diagrams 7B-32. . . . . . . . . .
A/C Diagrams 7B-32. . . . . . . . . . . . . . . . . . . . . . . . . . . .
A/C Airflow (Typical) 7B-33. . . . . . . . . . . . . . . . . . . . . .
A/C System (Typical) 7B-33. . . . . . . . . . . . . . . . . . . . .
MANUAL CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM 7B–13
DAEWOO M-150 BL2
REPAIR INSTRUCTIONS
ON-VEHICLE SERVICE
GENERAL A/C SYSTEM
SERVICE PROCEDURES
O-RING REPLACEMENT
Important: Even though O-rings may look identical, it is
extremely important that only recommended service re-
placement air conditioning O-rings be used, or exces-
sive leakage of refrigerant may occur.
Important: Always slip the O-ring onto the flange tube
to ensure proper locating and sealing.
Install new DAEWOO-approved service replacement air
conditioning O-rings whenever a joint or a fitting is disas-
sembled, except when the O-rings are provided on new
components.
When replacing O-rings on an air conditioning compo-
nent or a joint connection, the fitting design should be
identified to ensure installation of the correct air condi-
tioning service replacement O-ring.
Before installation, verify that both O-rings and fittings
have not been nicked or deformed. Deformed or nicked
parts must be replaced. Failure to use the proper service
replacement parts and procedures may result in exces-
sive refrigerant leakage.
HANDLING REFRIGERANT
Caution: Always work in a well-ventilated area and
avoid breathing any refrigerant fumes. If you have
difficulty breathing, seek medical attention immedi-
ately. If refrigerant comes in contact with any part of
your body, flush the exposed area with water. If a
rash or pain develops, seek medical attention.
Air conditioning systems contain refrigerant. This is a
chemical mixture which requires special handling proce-
dures to avoid personal injury.
Always wear goggles and wrap a clean cloth around the
fittings, the valves and the connections when performing
work that involves opening the refrigerant system. Do
not weld or steam clean on or near any vehicle-installed
air conditioning lines or components.
All refrigerant drums are shipped with a heavy metal
screw cap. The purpose of the cap is to protect the valve
and the safety plug from damage. It is good practice to
replace the cap after each use of the drum.
If it is necessary to transport or carry any container of
refrigerant in a vehicle, do not carry it in the passenger
compartment.
HANDLING OF REFRIGERANT LINES
AND FITTINGS
Notice: Using too low or too high torque when tightening
a fitting can result in loose joints or deformed joint parts.
Both conditions can result in refrigerant leakage.
Keep all metal tubing lines free of dents or kinks. Any
line restrictions will cause the loss of system capacity.
Never bend a flexible hose line to a radius of less than
four times the diameter of the hose.
Never allow a flexible hose line to come near the ex-
haust manifold.
Inspect flexible hose lines regularly for leaks or brittle-
ness.
Replace flexible hose lines with new lines if you find
signs of deterioration or leaking.
Discharge the refrigeration system of all refrigerant
before disconnecting any fitting in the refrigeration
system.
Proceed very cautiously regardless of the gauge
readings.
Open the fittings very slowly.
Keep your face and your hands away from the fitting
so that you will not be injured if there happens to be
liquid refrigerant in the line.
If you notice pressure when you loosen a fitting, allow
the pressure to bleed off as described under “Dis-
charging, Adding Oil, Evacuating and Charging Pro-
cedures for A/C System” in this section.
Cap or tape any refrigerant line immediately after it is
opened. This will prevent the entrance of moisture
and dirt, which can cause internal compressor wear
or plugged lines in the condenser, the evaporator
core, the expansion valve or the compressor inlet
screens.
Important: Use two proper wrenches to connect the O-
ring fittings.
Back up the opposing fitting to prevent distortion of
the connecting lines or the components.
Back up both the swaged fitting on the flexible hose
connections and the coupling to which it is attached
with two wrenches to prevent turning the fitting and
damaging the ground seat.
Keep the O-rings and the seats in perfect condition. A
burr or a piece of dirt may cause a refrigerant leak.
Dip new O-rings in clean PAG refrigerant oil before
installation.
7B–14 MANUAL CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM
DAEWOO M-150 BL2
MAINTAINING CHEMICAL STABILITY
IN THE REFRIGERATION SYSTEM
The efficient operation and life of the air conditioning
system is dependent upon the chemical stability of the
refrigeration system. When foreign materials, such as
dirt, air, or moisture, contaminate the refrigeration sys-
tem, they will change the stability of the refrigerant and
the PAG compressor oil. They will also affect the pres-
sure-temperature relationship, reduce efficient opera-
tion, and can possibly cause interior corrosion and
abnormal wear of moving parts.
Observe the following practices to ensure chemical sta-
bility in the system:
Wipe away dirt or oil at and near any connection be-
fore opening that connection. This will reduce the
chance of dirt entering the system.
Cap, plug, or tape both sides of a connection as soon
as possible after opening the connection. This will
prevent the entry of dirt, foreign material, and mois-
ture.
Keep all tools clean and dry, including the manifold
gauge set and all replacement parts.
Use a clean and dry transfer device and container to
add PAG refrigerant oil. This will ensure that the oil
remains as moisture-free as possible. Refer to “Dis-
charging, Adding Oil, Evacuating and Charging Pro-
cedures for A/C System” in this section.
Have everything you need ready to allow you to per-
form all operations quickly when opening an A/C sys-
tem. Do not leave the A/C system open any longer
than necessary.
Evacuate and recharge any A/C system that has
been opened. Refer to “Discharging, Adding Oil, Eva-
cuating and Charging Procedures for A/C System” in
this section for the instructions to perform this proce-
dure properly.
All service parts are dehydrated and sealed before ship-
ping. They should remain sealed until just before making
connections. All the parts should be at room tempera-
ture before uncapping. This prevents condensation of
moisture from the air from entering the system. Reseal
all parts as soon as possible if the caps have been re-
moved but the connections cannot be made promptly.
DISCHARGING, ADDING OIL,
EVACUATING, AND CHARGING
PROCEDURES FOR A/C SYSTEMS
Caution: Use only refillable refrigerant tanks that
are authorized for the charging station being used.
The use of other tanks may cause personal injury or
void the warranty. Refer to the manufacturer’s in-
structions for the charging station.Caution: To avoid personal injury, always wear
goggles and gloves when performing work that in-
volves opening the refrigeration system.
A charging station discharges, evacuates, and re-
charges an air conditioning system with one hook-up.
Filtering during the recovery cycle together with filtering
during the evacuation cycle ensures a supply of clean,
dry refrigerant for A/C system charging.
Notice:
Never use the R-134a charging station on a system
charged with R-12. The refrigerants and the oils are
not compatible and must never be mixed in even the
smallest amount. Mixing refrigerant residue will dam-
age the equipment.
Never use adapters which convert from one size fit-
ting to another. This will allow contamination which
may cause system failure.
Charging Station Setup and Maintenance
Refer to the manufacturer’s instructions for all initial set-
up procedures and all maintenance procedures. There
are many charging stations available. All perform the
various tasks required to discharge the system and re-
cover refrigerant, evacuate the system, add a measured
amount of oil, and recharge an air conditioning system
with a measured amount of refrigerant.
Control Panel Functions
A charging station will have controls and indicators to al-
low the operator to control and monitor the operation in
progress. Refer to the manufacturer’s instructions for
details. These can be expected to include:
1. Main Power Switch: The main power switch supplies
electrical power to the control panel.
2. Display: The display shows the time programmed for
vacuum and the weight of the refrigerant pro-
grammed for recharging. Refer to the manufacturer’s
instructions for detailed programming information.
3. Low Side Manifold Gauge: This gauge shows the
system’s low side pressure.
4. High Side Manifold Gauge: This gauge shows the
system’s high side pressure.
5. Controls: This will contain the controls that control
various operating functions.
6. Low Side Valve: This valve connects the low side of
the A/C system to the unit.
7. Moisture Indicator: This indicator shows if the refrig-
erant is wet or dry.
8. High Side Valve: This valve connects the high side of
the A/C system to the unit.
MANUAL CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM 7B–15
DAEWOO M-150 BL2
Refrigerant Recovery
Important: Use only a refrigerant tank that is designed
for the charging station in use. The unit’s overfill limita-
tion mechanism is calibrated specifically for use with this
tank. The tank’s valves are also specifically for this unit.
1. Attach the high side hose with the quick disconnect
coupler to the high side fitting of the vehicle’s A/C
system.
2. Open the coupler valve after attachment.
3. Attach the low side hose with the quick disconnect
coupler to the low side fitting of the vehicle’s A/C
system.
4. Open the coupler valve after attachment.
5. Check the high side and the low side gauges on the
unit’s control panel in order to ensure that the A/C
system has pressure. If there is no pressure, there
is no refrigerant in the system to recover.
Important: If there is no refrigerant in the system, do
not continue with the recovery operation. This will draw
air into the recovery tank.
6. Open both the high side and the low side valves.
7. Open the gas and the liquid valves on the tank.
8. Drain any oil that may be in the oil separator.
9. Close the oil drain valve.
10. Plug the unit into the proper voltage outlet.
11. Turn on the main power switch.
Notice: Never reuse refrigerant oil. Damage to the A/C
system may result. Dispose of the refrigerant oil proper-
ly.
12. Begin the recovery process. Refer to the manufac-
turer’s instructions for the charging station in use.
Important: Some A/C system PAG lubricating oil may
be removed with the refrigerant during recovery. The
amount of oil removed varies. A charging station sepa-
rates the oil from the refrigerant and allows a means of
determining how much oil was removed. Replace the
same amount of oil when you recharge the system. Re-
fer to the manufacturer’s instructions for the charging
station in use.
13. Wait 5 minutes. Check the control panel low side
gauge. If the A/C has maintained vacuum, the re-
covery is complete.
14. There is more refrigerant in the system if the low
side gauge pressure rises above zero. Recover the
additional refrigerant. Repeat this step until the sys-
tem maintains vacuum for two minutes.
Important: If the control indicator shows that the refrig-
erant tank is full during the recovery process and the unit
shuts off, install an empty unit tank to store the refriger-
ant needed for steps later in the procedure. Do not use
any other type of tank.
Evacuation
The unit tank must contain a sufficient amount of R-134a
refrigerant for charging. Check the amount of refrigerant
in the tank. If there is less than 3.6 kg (8 pounds) of re-
frigerant, add new refrigerant to the tank. Refer to the
manufacturer’s instructions for adding refrigerant.
1. Verify that the high side and the low side hoses are
connected to the A/C system. Open both the high
side and the low side valves on the unit’s control pan-
el.
2. Open both the gas and the liquid valves on the tank.
Important: Refer to the manufacturer’s instructions for
the charging station in use. It is necessary to evacuate
the system before recharging it with new or recycled re-
frigerant.
3. Start the vacuum pump and begin the evacuation
process. Non-condensable gases (mostly air) are au-
tomatically vented from the tank during the recycling
process. You may hear the pressure being released.
4. Check for leaks in the system. Refer to the manufac-
turer’s instructions for the charging station in use.
Important:
Change the vacuum pump oil frequently. Refer to the
manufacturer’s instructions for the charging station in
use.
A/C System Oil Charge Replenishing
Any oil removed from the A/C system during the recov-
ery process must be replenished at this time.
1. Use the correct graduated bottle of polyalkaline glycol
(PAG) oil for the R-134a system.
Important:
Keep the oil bottles tightly capped at all times to pro-
tect the oil from moisture and contamination.
Never open the oil injection valve while there is posi-
tive pressure in the A/C system. This will result in oil
blow-back through the bottle vent. You must have
A/C system vacuum for this operation.
Never let the oil level drop below the pick-up tube
while charging or replenishing the system. This will
allow air into the A/C system.
2. Refer to the manufacturer’s instructions for the charg-
ing station in use. Add the proper amount of PAG oil
to the system.
3. Close the valve when the required oil charge has
been pulled into the system.
Charging
Important: Evacuate the air conditioning system before
charging.
1. Close the low side valve on the control panel.
2. Open the high side valve on the control panel.
MANUAL CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM 7B–19
DAEWOO M-150 BL2
D18B504A
4. Remove the dual cut switch.
With the receiver dryer clothed, vise the receiver
dryer (1).
Remove the dual cut switch (2).
Discard the O–ring (3).
D18B505B
Installation Procedure
1. Install the new O–ring.
2. Install the dual cut switch.
Tighten the dual cut switch to 13 Nm (115 lb-in).
D18B506B
3. Install the receiver dryer.
Install the new O–rings.
Install the bracket bolt (1).
Tighten
Tighten the bracket bolt to 5 Nm (44 lb-in).
Install the receiver dryer flange nuts (2).
Tighten
Tighten the receiver dryer flange nut to 14 Nm (10.5
lb-ft).
Connect the dual cut switch connector.
4. Install the front bumper fascia. Refer to Section 9O,
Bumpers and Fascias.
5. Evacuate and recharge the system. Refer to “Dis-
charging, Adding Oil, Evacuating, and Charging Pro-
cedures for A/C System” in this section.
7B–20 MANUAL CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM
DAEWOO M-150 BL2
D108B507
RECEIVER DRYER BRACKET
Removal Procedure
1. Remove the front bumper fascia. Refer to Section
9O, Bumpers and Fascias.
2. Remove the receiver dryer bracket.
Remove the receiver dryer bracket bolt (1).
Remove the receiver dryer bracket–to–body bolts
(2).
D18B508B
Installation Procedure
1. Install the receiver dry bracket with the bolts.
Tighten
Tighten the receiver dryer bracket–to–body bolts
to 5 Nm (44 lb-in) (1).
Tighten the receiver dryer bracket bolt to 5 Nm
(44 lb-in) (2).
2. Install the front bumper fascia. Refer to Section 9O,
Bumpers and Fascias.
D108B509
D18B510A
COMPRESSOR
Removal Procedure
1. Remove the receiver dryer. Refer to “Receiver Dryer
and Dual Cut Switch” in this section.
2. Remove the A/C belt. Refer to Section 6B, Power
Steering Pump.
3. Remove the compressor.
Discharge and recover the refrigerant. Refer to
“Discharging, Adding Oil, Evacuating, and Charg-
ing Provedures for A/C System” in this section.
Remove the bolt securing the low pressure pipe
line to the compressor (1).
Remove the bolt securing the high pressure pipe
line to the compressor (2).
Disconnect the electrical connector (3).
Remove the upper bolt mounting the compressor–
to–bracket (4).
Remove the lower bolts mounting the compres-
sor–to–bracket (5).
MANUAL CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM 7B -- 21
DAEWOO M-150 BL2
D18B511B
Installation Procedure
1. Install the compressor with the mounting bolts.
Tighten
DTighten the compressor--to--bracket upper bolt to
20 NSm (15 lb-ft) (1).
DTighten the compressor--to--bracket lower bolts to
22 NSm (16 lb-ft) (2).
2. Connect the electrical connector.
D18B512A
3. Install the A/C high pressure pipe line to the compres-
sor with the bolt.
Tighten
Tighten the A/C high pressure pipe line bolt to 23 NSm
(17 lb-ft) (3).
4. Install the A/C low pressure pipe line to the compres-
sor with the bolt.
Tighten
Tighten the A/C low pressure pipe line bolt to 23 NSm
(17 lb-ft) (4).
5. Evacuate and charge the system. Refer to “Discharg-
ing, Adding Oil, Evacuating, and Charging Procedure
for A/C System” in this section.
6. Install the A/C belt. Refer toSection 6B, Power Steer-
ing Pump.
7. Install the receiver dryer. Refer to “Receiver Dryer
and Dual Cut Switch” in this section.
D18B513A
CONDENSER
1. Disconnect the negative battery cable.
2. Remove the front bumper fascia. Refer toSection
9O, Bumpers and Fascias.
3. Discharge and recover the refrigerant. Refer to “Dis-
charging, Adding Oil, Evacuating, and Charging Pro-
cedures for A/C system” in this section.
4. Remove the condenser.
DLoosen the condenser pipe--to--compressor pipe
fitting (1).
DLoosen the condenser pipe--to--receiver dryer pipe
fitting (2).
7B -- 22 MANUAL CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM
DAEWOO M-150 BL2
D18B514A
DRemove the condenser mounting nuts (3).
DPush the top of the condenser (4).
DTake off the condenser from the lower bracket by
lifting the condenser (5).
DRemove the condenser (6).
D18B515B
Installation Procedure
Important:Discard the removed O--rings.
1. Install the condenser with the nuts.
Tighten
Tighten the condenser mounting nuts to 4 NSm(36lb-
in).
D18B516B
2. Tighten the fittings and the bolt.
Tighten
DTighten the condenser pipe--to--compressor pipe
fitting to 23 NSm (17 lb-ft) (1).
DTighten the condenser pipe--to--receiver dryer pipe
fitting to 14 NSm (10.5 lb-ft) (2).
3. Evacuate and recharge the system. Refer to “Dis-
charging, Adding Oil, Evacuating, and Charging Pro-
cedures for A/C System” in this section.
4. Install the front bumper fascia. Refer toSection 9O,
Bumpers and Fascias.
5. Connect the negative battery cable.
D108B517
A/C HIGH PRESSURE PIPE LINE
(Left -- Hand Drive Shown, Right -- Hand
Drive Similar)
Removal Procedure
1. Disconnect the negative battery cable.
2. Remove the front bumper fascia. Refer toSection
9O, Bumpers and Fascias.
3. Discharge and recover the refrigerant. Refer to “Dis-
charging, Adding Oil, Evacuating, and Charging Pro-
cedures for A/C System” in this section.
4. Remove the A/C high pressure pipe line between the
compressor and the condenser.
DRemove the bolt securing the high pressure pipe
line to the compressor (1).