On later models (mid-1970's and later) covered by this guide, the receiver-dehydrator has been replaced by an accumulator/drier. The accumulator performs much in the same way as did the receiver unit on earlier vehicles. The accumulator serves as a storage unit for refrigerant, receiving vapors and liquid from the evaporator and is also used to purge the system of moisture like the receiver. The difference comes in the accumulator's location. It is normally found right after the evaporator in the refrigerant system, instead of before the evaporator (as with receiver-dehydrators). Like with the receiver units, the accumulator/driers have a great thirst for moisture and should ALWAYS be sealed to the atmosphere. Removal or installation should take place as quickly as possible in order to minimize exposure of the unit to the atmosphere.
REMOVAL & INSTALLATION
- Properly discharge and recover the refrigerant in the A/C system using a suitable recovery station.
- Disconnect the negative battery cable.
- Disconnect the accumulator inlet and outlet lines, then immediately cap all openings to prevent system contamination.
- If equipped, disengage the pressure cycling switch connection, then remove the switch.
- Remove the accumulator bracket bolts, then remove the accumulator assembly.
- Add the appropriate amount of refrigerant oil to the new accumulator assembly.
- Position the accumulator in the vehicle and secure using the bracket bolts.
- If equipped, install the pressure cycling switch and engage the connector.
- Lubricate the new O-rings with fresh refrigerant oil, then uncap the openings and install the lines.
- Connect the negative battery cable.
- After checking that all the refrigerant lines are properly tightened, evacuate, leak test and charge the system.