LG Air Conditioner Error Code E180

E180 means the system has detected that both the cooling and heating MCU solenoid valves opened at the same time, which is not a normal or safe operating condition. These two valves are supposed to operate exclusively of each other to route refrigerant in the correct direction. The system responds by stopping automatically and attempting a restart to recheck whether the fault is still present. If the simultaneous valve opening is confirmed on the next cycle, the fault will persist and require hands-on diagnosis.

You should not attempt to continue running the unit while the E180 fault is active or recurring. Simultaneous opening of both refrigerant control valves can disrupt refrigerant flow in ways that may damage the compressor or other sealed system components over time. The automatic stop the unit performs is a protective measure, and bypassing or repeatedly resetting through it without addressing the cause risks further damage.

Repair costs will vary depending on the root cause identified during diagnosis. If the issue is a corroded connector or a wiring short, repair costs may fall in a lower range covering labor only, typically somewhere between $75 and $200. Replacing a faulty solenoid valve coil or valve assembly can run between $150 and $400 depending on the unit model and parts availability. If the MCU itself needs replacement, costs can range from $300 to $600 or more, including parts and labor.

The system is designed to perform an automatic stop and then restart to recheck the valve states as part of its first-detection response. If the fault was caused by a brief transient electrical event, the system may recover on its own after the restart. However, if an underlying mechanical or electrical problem exists with the solenoid valves, wiring, or MCU, the error will return and the unit will need a technician to diagnose and repair the root cause.

The system already performs an automatic reset as part of its first-detection procedure for E180. A manual power cycle may temporarily clear the displayed code, but if the underlying fault with the solenoid valves or their control circuitry is still present, the error will return once the system attempts to switch between cooling and heating modes again. A proper repair of the faulty component is required to clear the code permanently.