Samsung Air Conditioner Error Code P505

The P505 error code on a Samsung air conditioner indicates an outdoor unit overload 2 protection control error. This fault is related to the compressor or motor protection circuitry in the outdoor unit detecting an overcurrent or overload condition on a secondary monitored channel. The system's protection logic triggers this code when current draw or thermal stress on a key outdoor component exceeds safe operating thresholds, causing the unit to shut down to prevent permanent damage.

Overload protection circuits in outdoor units continuously monitor the electrical load on the compressor and associated motors. When a component draws more amperage than the rated limit, or when thermal sensors detect heat buildup beyond safe levels, the control board logs this fault and halts operation. The "overload 2" designation suggests this is tied to a specific secondary protection loop, which may monitor a fan motor, a secondary compressor winding, or an additional current sensing circuit separate from the primary overload protection path.

Common contributors to this fault include refrigerant charge issues, restricted airflow across the condenser coil, a failing compressor drawing high current, or a defective overload relay or protection component on the control board. Electrical supply problems such as low voltage or phase imbalance in multi-phase systems can also force components to draw excess current. A thorough diagnosis should include measuring supply voltage, checking amperage draw on outdoor unit components, inspecting the condenser coil for blockage, and verifying refrigerant pressure levels before replacing any parts.