Caution! The air conditioning system is under high pressure. Do not loosen any hoses or fittings or remove any parts until the system has been discharged. Air conditioning refrigerant should only be disposed of in a special container at an automotive air conditioning repair shop. Always wear safety glasses when disconnecting air conditioning system hoses.
Caution! Vehicles manufactured since 1994 use non-ozone-depleting R-134a refrigerant in the air conditioning system. R-134a refrigerant and its lubricating oil are not compatible with the R-12 system used in vehicles manufactured before 1993. Under no circumstances should R-12 refrigerant or R-12 refrigerant oil be added to an R-134a system or vice versa. Mixing different types of refrigerants and/or oils will cause damage to the air conditioning system.
Examination
1. To ensure that your air conditioner operates at maximum efficiency, the following checks should be performed regularly.
- a) Check the drive belt. If it is worn out or has lost its qualities, replace it (see chapter 1, section 21).
- b) Check the air conditioning system hoses. Check for cracks, bulges, or signs of wear. Check the hoses and pipes for oil bubbles or signs of fluid leakage. Replace the hose(s) if there is any sign of wear, damage or leaks.
- c) Check that there are no leaves, insects or other contaminants left in the evaporator fins. To clean the evaporator, you can use a source of compressed air.
- d) Check that the system is filled with sufficient refrigerant.
2. It is recommended to turn on the system for about 10 minutes at least once a month, especially in winter. Long periods of non-use of the system may result in hardening and subsequent wear of all oil seals.
3. Due to the complexity of the air conditioning system and the need to use special equipment to service this system, a more in-depth analysis of the malfunctions that occur and the necessary repairs is not included in this manual. However, this chapter contains some simple checks and descriptions of replacement procedures for some parts.
4. The most common reason for poor air conditioning performance is insufficient refrigerant charge. If the system is producing little cool air, you can perform one of the following tests to determine if the refrigerant level is low.
5. Warm up the engine to normal operating temperature.
6. Set the air conditioning temperature selector to the lowest temperature setting and the blower to maximum flow. Open the doors (to ensure the operation of the air conditioning system while cooling the interior).
7. When the compressor starts working (the compressor clutch will make an audible click and the clutch center will begin to rotate) feel the outlet pipe located near the right front frame member next to the radiator.
8. If a drop in temperature is noticeable, then the coolant level is probably OK (see chapter 6, section 4 for information on the air conditioning clutch control system). Further testing of the system should be performed by a professional repairman.
9. If frost builds up on the inlet pipe or it is colder than the filter surface, the refrigerant charge is low. On models produced before 1993 and earlier, a technician or service representative must charge the air conditioning system. If you have a 1994 model year vehicle, see below.
Refrigerant addition (only for systems with R-134a refrigerant)
Note: Due to recent EPA regulations, R-12 refrigerant used in 1993 and earlier models is no longer produced.
10. Obtain a canister of R-134a refrigerant and a canister opener tool designed to work with the R-134a connection. This tool has a short piece of tubing that can be attached between the valve of the unit and the charging valve on the bottom. One canister of refrigerant may not be enough to charge the system to the required level.
Caution! Never add more than 2 cans of refrigerant to the system.
11. Connect the tamper evident valve to the canister and the end of the hose to the downstream side of the system, following the tamper evident valve manufacturer's instructions. Do not open the canister at this time.
Caution: Do not connect the hose to the top of the system.
12. Warm up the engine and turn on the air conditioning system. Keep the hose away from the fan and other moving parts.
13. Following the can opener manufacturer's instructions, add refrigerant to the low side of the system until the filter surface and the evaporator inlet feel like they are the same temperature. Allow some time for stabilization before adding refrigerant.
14. When the surface of the filter drier and the evaporator inlet pipe seem equally hot, add the remaining refrigerant in the canister.
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