LG Heat Pump Error Code CH16

CH16 is a general sensor fault code indicating that the LG heat pump's control board has detected an abnormal or missing signal from one or more temperature sensors. The system expects a sensor resistance of 5k ohm at 25 degrees Celsius when unplugged, and a reference voltage of 2.5Vdc at 25 degrees Celsius when connected. When the actual reading falls outside this range, the unit triggers CH16 and halts normal operation to prevent damage.

It is not advisable to continue operating the unit while CH16 is active. The heat pump uses sensor data to regulate its refrigeration cycle and protect components from overheating or over-pressurization. Without reliable sensor input, the system cannot make safe control decisions, which could lead to additional component damage over time.

Repair costs vary depending on the cause. A sensor replacement typically falls in the range of 75 to 250 dollars including parts and labor, depending on which sensor is at fault and its location in the system. If the PCB requires replacement, costs can range from 300 to 800 dollars or more depending on the unit model and regional labor rates. Getting a diagnostic service call first helps narrow down the exact component involved before committing to a repair.

Some causes of CH16 can be addressed without specialized tools, such as reseating a loose sensor connector or cleaning corroded terminals. However, accurately diagnosing a faulty sensor requires a multimeter to measure resistance and voltage against the specified values. Replacing sensors or a PCB involves working inside the unit and handling refrigerant-adjacent components, so professional service is recommended if basic connector checks do not resolve the fault.

A power reset may temporarily clear the CH16 code if the fault was caused by a transient electrical disturbance or a briefly unseated connector. However, if an underlying hardware problem exists such as a failed sensor or damaged wiring, the code will return once the unit resumes operation and the PCB detects the out-of-range signal again. Resetting without diagnosing the root cause is not a reliable fix.