To replace the A/C evaporator core in BMW 3 series models, begin by discharging the air conditioning refrigerant through a BMW dealer or specialist. Then, in the engine compartment, remove the in-cabin air filter and heater/ventilation inlet air ducting, followed by the heater core and instrument panel. In the engine compartment, release the right air intake flap from the blower housing, disconnect the air conditioning lines from the firewall, and remove the air conditioning blower limit switch. Disconnect the temperature sensor, unclip the linkage from the servo motor, and release wiring connectors and harnesses. Remove the lower part of the evaporator housing and the A/C evaporator core itself, taking care not to damage the cooling fins. For Z4 models, remove the heater assembly, adapter plate, evaporator cover, and expansion valve. For the expansion valve, discharge the refrigerant, remove the in-cabin air filter and air intake flap, disconnect the air conditioning lines, and replace the valve. In Z4 models, remove the refrigerant line clamps, disconnect the air conditioning lines from the firewall, and replace the expansion valve. For the A/C accumulator, replace it when necessary and discharge the refrigerant. Remove the pipes and coupling, then lower the A/C accumulator from the clamp. Finally, for the compressor, discharge the refrigerant, raise the vehicle, and remove the engine splash shield and drive belt. Remove the front windshield wiper fluid reservoir, disconnect the wiring connector, and disconnect the air conditioning lines from the compressor. Remove the compressor and install it with the correct amount of refrigerant oil, new seals, and have it recharged. Additionally, for the HVAC Pressure Switches, disconnect the wiring connector and unscrew the switches from the A/C accumulator. Reinstall them securely and have the refrigerant recharged. For the condenser, discharge the refrigerant and remove the air filter housing and radiator. Disconnect the refrigerant lines from the condenser and remove it. Install the new condenser with the correct amount of refrigerant oil and new seals, and have it recharged. Finally, for the blower limit switch, unclip the right-hand footwell air duct, pry the linkage arm from the servo motor, and remove the bracket, servo motor, and switch. Reinstall it following the reverse of removal steps.
Posted by BMWPartsDeal Specialist