LG Air Conditioner Error Code 216

Error code 216 on an LG air conditioning system signals a transmission error between HR unit 4 and the outdoor unit. This means communication between the branch controller box and the main outdoor unit has been lost or is corrupted. The system cannot operate the affected zones normally until the fault is resolved. A technician will check wiring connections and the HR unit 4 PCB communication LED as first steps.

A system reset may temporarily clear the error code, but it will return if the underlying communication fault is not corrected. Error 216 is tied to an active hardware or wiring problem between HR unit 4 and the outdoor unit. Resetting without fixing the root cause is not a solution and could mask the issue while leaving the system in a degraded or non-operational state.

Repair costs depend on the root cause. If the fault is simply a loose or damaged cable, costs are primarily labor and can range from roughly $100 to $300. If HR unit 4 requires a new PCB, parts and labor combined can range from $300 to $800 or more depending on the specific board and local service rates. A technician will need to diagnose the exact cause before providing an accurate estimate.

Basic checks such as visually inspecting cable connections at HR unit 4 and the outdoor unit can be done by a knowledgeable homeowner, but this type of VRF heat recovery system involves high-voltage wiring and complex communication networks. Diagnosing the PCB or rewiring transmission cables is best left to a qualified HVAC technician. Attempting internal repairs without proper training could create safety hazards or cause additional damage.

Operating the system with an active error 216 is not recommended. The outdoor unit cannot properly communicate with HR unit 4, which means refrigerant flow and zone control for that branch may be unreliable or completely non-functional. Continued operation in a fault state can place additional stress on other system components. The system should be diagnosed and repaired before resuming normal use.