LG Air Conditioner Error Code E554

E554 on an LG air conditioner indicates a gas leak error, specifically that the outdoor unit has detected full or near-complete refrigerant leakage. The system monitors the indoor evaporator sensor and refrigerant pressures to detect this condition. When refrigerant is critically low or absent, the unit will shut down and display E554 to prevent compressor damage.

No, you should not attempt to run the unit while E554 is active. Operating a system with critically low or absent refrigerant places extreme stress on the compressor and can cause permanent damage within a short time. Additionally, refrigerant leaks can pose environmental and health hazards depending on the refrigerant type and the concentration in an enclosed space.

A simple power reset will not permanently clear E554 because the fault is tied to an actual system condition, specifically low or absent refrigerant. The unit may restart briefly after a reset but will redetect the fault and display E554 again once it runs its diagnostics. The underlying cause, whether a leak, a closed service valve, or a faulty EVA sensor, must be corrected before the error will stay cleared.

Most of the hands-on repair for E554 requires EPA Section 608 certification to legally handle refrigerants, so the recharge portion must be performed by a licensed technician. However, a homeowner can check that the outdoor unit service valves are fully open and inspect visible pipe connections for oily residue, which indicates a leak. Any confirmed refrigerant leak must be repaired and the system properly recharged by a professional before the error will clear.

Repair costs depend on where the leak is located and how much refrigerant needs to be replaced. Leak detection and repair labor alone can range from around $150 to $400 or more, and refrigerant recharge costs vary based on the type and quantity required, often adding another $100 to $350. If the leak caused compressor damage due to running low on refrigerant, costs can be significantly higher.