LG Heat Pump Error Code E183

E183 indicates that during the system's piping check routine, an unexpected change in evaporator inlet temperature was detected at a secondary indoor unit. This suggests that refrigerant is flowing through an unintended circuit, pointing to a piping connection error, crossed refrigerant lines, or a faulty component like an expansion valve or thermistor. The system flags this condition to prevent improper operation resulting from incorrect refrigerant routing.

It is not advisable to continue running the system while E183 is active. The error indicates that refrigerant distribution may not be functioning as intended, which can result in inefficient operation, inadequate heating or cooling, and potential stress on system components. Shutting down the unit and scheduling a diagnostic inspection is the safest course of action.

A power reset may temporarily clear the E183 code, but it will return if the underlying piping or component issue is not resolved. The error is generated during the piping check routine, so each time the system runs that sequence, it will detect the same problem and re-trigger the fault. A lasting fix requires identifying and correcting the root cause of the unintended refrigerant temperature change.

Some causes of E183, like wiring errors or improperly labeled piping connections, may be accessible to a knowledgeable DIYer who is familiar with multi-zone HVAC systems. However, any work involving refrigerant lines or expansion valves requires an EPA 608-certified technician. Because the error involves refrigerant circuit verification, professional diagnosis is strongly recommended.

Repair costs vary widely depending on the root cause. If the fix involves correcting piping or wiring connections, labor costs alone might range from $100 to $300. If a thermistor or electronic expansion valve needs replacement, parts and labor combined could range from $200 to $600 or more. A full diagnosis from a certified technician is needed to provide an accurate estimate.