Q: How to Replace the Receiver-Drier in an R-134a A/C System?A: Have an AC technician discharge and recover the refrigerant. Disconnect the battery's negative terminal, remove the refrigerant lines from the A/C accumulator, and cap them to prevent dirt or moisture entry. Disconnect the pressure switch's electrical connector, remove the A/C accumulator's bracket bolt, and remove the unit. Install new O-rings onto the line fittings, lightly coat them with refrigerant oil, and tighten the fittings. Use only AC-specific O-rings. If replacing the A/C accumulator, add 10 ml of refrigerant oil. Reconnect the battery and have the system evacuated, charged, and leak tested. Add additional refrigerant oil when replacing components. Ensure oil compatibility with the R-134a system. Note: On certain models, the A/C accumulator is integrated with the condenser and not separately serviceable.