Refrigerant Circuit Components, Replacing: Notes
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→ Leaking or Damaged Components except Compressor, Reservoir, or Receiver
→ Compressor, Replacing without Flushing Refrigerant Circuit
→ Compressor, Replacing Due to Leakage or Internal Damage
→ Receiver or Accumulator and Restrictor, Replacing after Cleaning Refrigerant Circuit
→ Receiver or Reservoir, Replacing without Flushing Refrigerant Circuit
- All components of the refrigerant circuit submitted for quality observation are always to be sealed (use original sealing caps of replacement part).
- To date, the replacement parts "compressor, reservoir, receiver, evaporator and condenser" have been filled with nitrogen gas. This charge is being gradually discontinued/the pressure of the nitrogen charge is now so low that escape of gas is no longer perceptible on initial opening.
- On vehicles equipped with a compressor with no A/C clutch, the engine is only to be started following complete assembly of the refrigerant circuit (compressor always in operation as well).
- When the refrigerant circuit is empty, the compressor with A/C Compressor Regulator Valve N280 (without A/C clutch) is switched to internal lubrication with the result that only a minimal amount of oil is pumped from the compressor into the circuit.
NOTE:
- As parts are sometimes stored for lengthy periods and at different locations within the spare parts organization, it is entirely possible that gas will escape from some parts and not from others on initial opening (even in the case of identical spare part numbers). Sealing caps at replacement part connections are therefore to be removed carefully and the nitrogen gas allowed to escape slowly.
- The refrigerant circuit is equipped either with a restrictor and reservoir or an expansion valve and receiver.
- Dryer cartridge or components with desiccant bag (reservoir, receiver) are always to be replaced after flushing refrigerant circuit; in doing so, leave sealed as long as possible to minimize absorption of moisture.
- Dryer cartridge or components with desiccant bag (reservoir, receiver) are always to be replaced after cleaning refrigerant circuit (flushing with refrigerant R134a → Refrigerant Circuit, Flushing with Refrigerant R134a or blowing through using compressed air and nitrogen → Refrigerant Circuit, Flushing with Compressed Air and Nitrogen ); in doing so, leave sealed as long as possible to minimize absorption of moisture.
- The period of time for which a refrigerant circuit may be left open without having to replace a component with desiccant bag (reservoir, receiver) is largely governed by ambient influences. Given a high ambient temperature and a high humidity level or if the vehicle has been standing in the open for example or driven (in wet, foggy weather conditions), the period will be considerably shorter than for a vehicle which has been standing in a heated dry area. The size of the opening through which moisture may enter into the circuit also influences the period for which a refrigerant circuit can be left open without having to replace components with desiccant bag.
- Seal open connections and pipes (to prevent absorption of moisture).
- Always replace restrictor.
CAUTION:
- Contaminated refrigerant oils are to be disposed of as used oils of unknown origin.
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