General Air Conditioning Maintenance Procedures (Chevrolet Captiva 1)

Replacing the sealing rings

Important: Although the O-rings may look identical, it is extremely important to ensure that only the O-rings recommended for replacement are used when servicing the air conditioning system, otherwise a major refrigerant leak may occur.

Important: The O-ring must always be placed on the flange tube to ensure proper positioning and sealing.

New O-rings from repair kits recommended by Daewoo must be installed at each disassembly of joints or fittings, except when the O-rings are supplied complete with new parts.

When replacing O-rings on an air conditioner assembly or joint, it is important to determine the fitting design to ensure that the correct O-ring from the repair kit is installed. Some joints and assemblies use a fitting with a "capturing" O-ring design, which uses a groove to retain the O-ring. Other assemblies do not have a groove, and a "non-capturing" or "standard" O-ring is used. The assembly and tightening procedures for both types are the same, but the O-rings are different.

Note: Before installation, make sure that neither the O-ring nor the fitting is damaged or deformed. Deformed or damaged parts must be replaced. Failure to follow the instructions for using the correct type of replacement parts and procedures may result in excessive refrigerant leakage.

Handling refrigerant

Warning! Work in a well-ventilated area and avoid inhaling refrigerant vapors. If breathing becomes difficult, seek medical attention immediately. If refrigerant comes into contact with any part of the body, rinse it with running water. If a rash or pain occurs, seek medical attention.

Air conditioning systems contain refrigerant, a chemical compound that requires special handling to avoid injury.

When performing work related to opening the refrigeration system, always wear safety glasses and wrap fittings, valves and connections in a clean cloth. Do not weld or steam clean on or in the immediate vicinity of vehicle-mounted air conditioning system assemblies and lines.

All refrigerant cylinders are supplied with a heavy metal screw cap. This cap is designed to protect the valve and safety plug from damage. It is strongly recommended to replace this cap after each use of the cylinder.

If it is necessary to transport a container with refrigerant by car, do not transport it in the passenger compartment.

Handling refrigerant pipes and fittings

Note: Too little or too much tightening torque on a fitting will cause the connections to become loose or parts to become deformed. Both of these conditions may result in refrigerant leakage.

• Keep all metal piping free from dents and bends. Any line restriction will result in poor system performance.
• It is prohibited to bend the flexible hose with a radius less than four hose diameters.
• Flexible hoses must not be placed closer than 65 mm (2-1/2 inches) to the exhaust manifold.
• Regularly inspect flexible hoses for leaks or brittleness.
• If signs of deterioration or leakage are detected, replace the flexible hoses with new ones.
• Before disconnecting any fitting on a refrigeration system, it is necessary to evacuate all refrigerant from the system.
• Exercise caution regardless of instrument readings.

Caution: Keep your face and hands away from the fitting to avoid injury if there is liquid refrigerant in the line.

• Open the fitting slowly.
• If pressure is detected while releasing the fitting, relieve the pressure as described in paragraph "Procedures for discharging, refilling oil, vacuuming and charging the air conditioning system" in this section.
• Immediately after opening any refrigerant line, cap or tape it. This prevents moisture and dirt from entering the system, which can cause internal wear of the compressor and the lines running through the condenser, evaporator coil, expansion valve, and compressor inlet strainers.

Important: To connect fittings with O-rings, use two wrenches of the appropriate size.

• Support the mating fitting to avoid deformation of the connecting pipes or components.
• It is necessary to support both the free fitting of the connector on the flexible hose and the mating part of the connector to which it is attached using two keys to avoid turning the fitting and damaging the bottom of the socket.
• The sealing rings and seats must always be in perfect condition. A burr or dirt particle can cause a refrigerant leak.
• Before installation, new O-rings should be immersed in clean polyalkylene glycol compressor oil.

Maintaining stability of chemical composition in the refrigeration system

The reliability of the operation and durability of the air conditioning system depends on the stability of the chemical composition in the refrigeration system. When the refrigeration system is contaminated with foreign materials (dirt, air or moisture), the stability of the chemical composition of the refrigerant and polyalkylene glycol (PAG) compressor oil is disrupted. In addition, the dependence of pressure on temperature changes, the efficiency of operation deteriorates, and internal corrosion and excessive wear of moving parts may occur.



To ensure the stability of the chemical composition in the system, the following recommendations must be followed:

• Before opening any connection, it is necessary to wipe away dirt and oil around it. This reduces the risk of dirt getting into the system.
• Once the connection has been opened, both ends of the connection must be closed as quickly as possible with a cap, plug or tape. This prevents dirt, foreign materials and moisture from entering the system.
• All tools, including the manifold gauge kit, and all spare parts must be clean and dry.
• When filling polyalkylene glycol compressor oil, use a clean and dry filling device and container. This will prevent moisture from getting into the oil as much as possible. See "Procedures for discharging, refilling oil, vacuuming and charging the air conditioning system" in this section.
• Everything you need should be at hand so that when opening the air conditioning system, all operations can be performed quickly. Do not leave the air conditioning system open longer than necessary.
• Evacuate and recharge the air conditioning system that has been opened. For instructions on how to perform these procedures, see paragraph "Procedures for discharging, refilling oil, vacuuming and charging the air conditioning system" in this section.

All spare parts are dehydrated and sealed before delivery. They must remain sealed until immediately before installation. When opened, all parts must be at room temperature. This prevents condensing moisture from the air from entering the system. All parts must be sealed as quickly as possible.

Procedures for discharging, refilling oil, vacuuming and charging the air conditioning system

Warning! Use only refillable refrigerant cylinders approved for use in charging stations. Use of other cylinders may result in personal injury and void the warranty. Refer to the manufacturer's instructions for use of the charging station.

Caution: Always wear safety glasses and gloves when performing any work involving opening the refrigeration system to avoid injury.

The charging station discharges, evacuates and charges the air conditioning system with a single unit. Filtering the refrigerant during the pump down cycle, along with filtering during the evacuation cycle, ensures that clean, dry refrigerant is supplied to charge the air conditioning system.

Note: Do not use the R-134A charging station for systems charged with R-12 refrigerant. Refrigerants and oils from different systems are not compatible with each other and should not be mixed, even in small quantities. Mixing refrigerant residues will damage the equipment.

It is prohibited to use adapters from one size of fittings to another. Such connections create contamination that can lead to system failure.

Setting up and operating the charging station

There are many charging stations available. They all perform the various tasks required to discharge the system and recover the refrigerant, evacuate the system, add a measured amount of oil, and charge the air conditioning system with a measured amount of refrigerant. Refer to the manufacturer's instructions for all initial setup and operation procedures.

Control Panel Functions

The charging station has controls and indicators that allow the operator to control and monitor the processes being carried out. For more detailed information, see the manufacturer's instructions. As a rule, these include the following elements:

1. Main power switch

• Provides power to the control panel.

2. Indicator

• Shows the programmed time for vacuuming.
• Shows the programmed mass of refrigerant for charging.
• For programming details, please refer to the manufacturer's instructions.

3. Pressure gauge for low pressure side branch pipe

• Shows the pressure on the low pressure side of the system.

4. Pressure gauge for high pressure side pipe

• Shows the pressure on the high pressure side of the system.

5. Controls on the panel

• Control various work functions.

6. Low pressure side valve

• Connects the low pressure side of the air conditioning system to the station.

7. Moisture indicator

• Shows whether the refrigerant is wet or dry.

8. High pressure side valve

• Connects the high pressure side of the air conditioning system to the station.

Refrigerant recovery

Important: Use only refrigerant cylinders that are designed for the charging station you are using. The overflow limiter mechanism of the station is calibrated for the specific type of cylinders. The cylinder valves are also adapted to the specific type of station.

1. Connect the high pressure side hose using a quick disconnect connector to the high pressure fitting of the vehicle's air conditioning system.

2. Open the valve on the connector.

3. Connect the low pressure side hose using a quick disconnect connector to the low pressure fitting of the vehicle's air conditioning system.

4. Open the valve on the connector.

5. Check the high and low side pressure gauges on the station control panel to ensure that there is pressure in the A/C system. If there is no pressure, there is no refrigerant in the system to recover.

Important: If there is no refrigerant in the system, the pumping operation must be stopped, which under these conditions will pump the air into the pumping cylinder.

6. Open both valves on the high and low pressure sides.

7. Open the gas and liquid valves on the cylinder.

8. Drain any oil that may be in the oil separator.

9. Close the oil drain valve.

10. Connect the station to a socket with the appropriate voltage.

11. Turn on the main power switch.

Note: Do not reuse compressor oil. Reusing oil may cause damage to the air conditioning system. Dispose of compressor oil according to applicable regulations.

12. Start the pumping process. Refer to the manufacturer's instructions for the charging station you are using.

Important: During the pump down process, some polyalkylene glycol (PAG) lubricating oil may be removed. The amount of oil removed may vary. The charging station separates the oil from the refrigerant and provides a means to determine the amount of oil removed. An equal amount of oil must be added when the system is recharged. Refer to the manufacturer's operating instructions for the charging station being used.

13. Wait 5 minutes, then check the suction gauge on the control panel. If the air conditioning system maintains a vacuum, the pumping is complete.

14. If the pressure on the low pressure gauge is above zero, there is refrigerant left in the system. Evacuate the remaining refrigerant. Repeat this operation until the vacuum in the system is maintained for 2 minutes.

Important: If the control indicator shows that the refrigerant cylinder is full during the recovery process and the unit shuts down, install an empty cylinder to collect the refrigerant needed for subsequent operations in this procedure. Do not use other types of cylinders.

Vacuuming

The station cylinder must contain enough R-134a refrigerant for charging. Check the amount of refrigerant in the cylinder. If it contains less than 3.6 kg (8 lbs) of refrigerant, fresh refrigerant must be added to the cylinder. Refer to the manufacturer's instructions for adding refrigerant.

1. Make sure the low and high pressure side hoses are connected to the air conditioning system. Open both the high and low pressure side valves on the station control panel.

2. Open both valves (gas and liquid) on the cylinder.

Important: Refer to the manufacturer's operating instructions for the charging station being used. The system must be evacuated before charging the system with new or recycled refrigerant.

3. Turn on the vacuum pump and start the vacuuming process. Non-condensable gases (mainly air) are removed from the cylinder automatically during the system recharging process. A pressure drop can be heard.

4. Check for leaks in the system. Refer to the manufacturer's operating instructions for the charging station you are using.

Important: Change the oil in the vacuum pump regularly. Refer to the manufacturer's operating instructions for the charging station you are using.

Refilling the air conditioning system with oil

The oil removed from the air conditioning system during the pumping process must be replenished at this stage.

1. Use a flask of PAG oil of the appropriate grade for the R-134a system.

1. Use a flask of PAG oil of the appropriate grade for the R-134a system.

Important:

• Oil bottles must be kept tightly closed at all times to prevent moisture and contaminants from entering the oil.
• For this operation, it is necessary to maintain a vacuum in the air conditioning system. Do not open the oil filling valve when the pressure in the air conditioning system is positive. This will cause oil to flow back through the neck of the bottle.
• Do not allow the oil level to drop below the feed tube when charging or refilling the system, as this will allow air to enter the air conditioning system.

2. Refer to the manufacturer's operating instructions for the charging station being used. Add the appropriate amount of PAG oil to the system.

3. Close the valve after the required amount of oil has been pumped into the system.

Charger

Important: The system must be evacuated before charging.

1. Close the low pressure side valve on the control panel.

2. Open the high pressure side valve on the control panel.

3. Please refer to the manufacturer's operating instructions for the charging station you are using.

4. Enter the amount of refrigerant required to charge the air conditioning system, making sure to select the correct unit of measurement - kilograms (kg) or pounds (lb).

5. Start the charging process.

The download was successful

1. Close the high pressure side valve on the station control panel. Both valves should be closed.

2. Start the engine and turn on the air conditioning system.

3. Let the engine run until the high and low pressure side gauge readings stabilize.

4. Compare the readings with the data in the technical specifications.

5. Check the evaporator outlet temperature to ensure the air conditioning system is operating within system specifications.

6. Leave the air conditioner running.

7. Close the connector valve on the high pressure side.

8. Disconnect the high pressure side hose from the vehicle.

9. Open the high and low pressure side valves on the control panel. The system will quickly draw refrigerant from the two hoses through the low pressure side hose.

10. Close the connector valve on the low pressure side.

11. Disconnect the low pressure side hose from the vehicle.

The transfer was unsuccessful

Sometimes the entire portion of refrigerant is not pumped into the air conditioning system. This can happen for two reasons:

1. Almost the same pressure in the station cylinder and in the air conditioning system.

• For this reason, the pumping will be too slow.
• Please refer to the manufacturer's operating instructions for the charging station you are using.

2. The station's cylinder did not have enough coolant to fully charge it.

• It is necessary to evacuate a partial charge of refrigerant from the vehicle's system, and then re-evacuate and recharge the air conditioning system.
• Please refer to the manufacturer's operating instructions for the charging station you are using.