Samsung Mini Split C122 Error Code
Quick answer
C122 means an evaporator sensor fault - the service manual lists C122/C123 as the indoor mid / indoor-in evaporator (EVA-TH) temperature sensor error, matching the E122 evaporator-sensor convention on other Samsung lines. One source (SplitAtlas, WindFree Premium) reads C122 as a motion sensor error instead; models with an AI motion sensor can also flag it, so confirm on your model.
Severity: medium · DIY difficulty: simple
Safety
Only a power-cycle reset and visual checks you can do without removing any panel. Do not open the indoor or outdoor unit, test board voltages, touch capacitors (they hold lethal charge), re-pin wiring, or replace PCBs.
What C122 means
C122 means an evaporator sensor fault - the service manual lists C122/C123 as the indoor mid / indoor-in evaporator (EVA-TH) temperature sensor error, matching the E122 evaporator-sensor convention on other Samsung lines. One source (SplitAtlas, WindFree Premium) reads C122 as a motion sensor error instead; models with an AI motion sensor can also flag it, so confirm on your model.
Code meaning varies by series
- Samsung AR09TXFYAWKNEU service manual, indoor display table: C122, C123 Indoor MID / Indoor IN EVA-TH sensor error
- SplitAtlas (WindFree Premium): C122 motion sensor error - variant reading; motion-sensor faults are C143 on the AR09TXFYAWKNEU table.
Causes, ranked
1. Evaporator mid/in thermistor drifted open/short or out of resistance range occasional diy-ok
Check: One power-cycle reset at the breaker (3 minutes). A transient sensor reading may clear; if C122 returns immediately, the sensor or its connection is failing.
Fix: If the code clears and stays clear, no repair needed. Otherwise book service.
2. Loose or corroded sensor connector / damaged harness on the indoor coil occasional pro-only
Check: Technician only: sensor connector seating and harness continuity behind the indoor panel.
Fix: Technician: reseat or replace the connector/harness.
3. Failed EVA-TH thermistor or indoor PBA input occasional pro-only
Check: Technician only: measure sensor resistance against the temperature-resistance chart.
Fix: Technician: replace the evaporator thermistor; if the sensor tests fine, evaluate the indoor PBA.
4. Motion sensor fault (variant reading on WindFree AI models) occasional pro-only
Check: Technician only: verify which subsystem flagged C122 on your model via error-history readout.
Fix: Technician: clean/reseat or replace the motion sensor module if it is the flagged component.
Related codes
samsung/c101 · samsung/c123 · samsung/c121
Sources
- Samsung AR09TXFYAWKNEU service manual - indoor display errors (C122/C123 EVA-TH sensor) — verified 2026-08-29
- Samsung split-type error codes (service-manual-sourced list, C122/C123 EVA-TH sensor) — verified 2026-08-29
- SplitAtlas Samsung C122 page (variant reading: motion sensor error) — verified 2026-08-29