Samsung Refrigerator Error Code 24 usually points to a defrost-related problem, most often a failed defrost heater circuit or an open component in the evaporator defrost system. The single most likely fix is to inspect and replace the faulty defrost heater, defrost sensor, or damaged wiring harness after performing a full power reset.
Unplug the refrigerator or switch off the breaker for 15 to 30 minutes, then restore power. This clears temporary PCB logic faults and can reset a false error caused by a voltage glitch or interrupted defrost cycle. If the code returns, move to the next step.
The most common real fix is checking the defrost heater and defrost sensor at the evaporator assembly. If the heater is open, the thermal fuse has blown, or the thermistor is out of range, the control board will detect a defrost failure and trigger Error Code 24.
For a deeper diagnostic check, inspect the wiring harness from the evaporator section to the main control board and test continuity with a multimeter. If the heater circuit and sensor values are normal but the error persists, the main PCB may not be sending or reading the defrost signal correctly.
On a Samsung Refrigerator, Error Code 24 generally indicates a fault in the defrost system, especially around the freezer evaporator circuit. During normal operation, the control board energizes the defrost heater at set intervals to melt frost from the evaporator coils. If the PCB does not detect the expected temperature change through the thermistor or senses an open heater circuit, it stores the fault and displays the code.
In practical terms, this means frost can build up around the evaporator cover and fan area, reducing airflow and causing cooling problems in both compartments. A restricted evaporator often leads to warm temperatures, unusual fan noise, or poor ice production. The root cause is commonly a failed heater, bad defrost sensor, blown thermal fuse, loose connector, or a damaged wiring harness.
Although the control board itself can fail, that is less common than a component failure in the defrost circuit. Start with the heater assembly, thermistor, and harness before replacing any PCB. Accurate testing matters because a simple open circuit in one small component can shut down the entire automatic defrost process.
The defrost heater warms the evaporator during the defrost cycle to melt accumulated frost. If the heater element is open or burned out, the refrigerator cannot clear ice buildup, and the control board may trigger Error Code 24.
The defrost sensor monitors evaporator temperature and reports it back to the main PCB. If the thermistor resistance is out of range or the sensor is shorted or open, the board cannot confirm that defrost is working correctly.
Many Samsung refrigerators use a thermal fuse in the defrost circuit as a safety device. If that fuse opens, the heater loses power completely, and the board sees a failed defrost condition even if the heater itself still tests good.
Moisture, vibration, and repeated temperature changes can damage wires near the evaporator cover or connectors at the sensor and heater. A loose plug, corroded terminal, or broken wire can interrupt continuity and mimic a failed component.
If the heater, fuse, thermistor, and harness all test correctly, the main PCB may not be switching voltage to the heater relay or reading the sensor circuit properly. This is less common, but it does happen after power surges or capacitor failure on the board.
Follow the steps below one at a time — many error codes can be fixed faster than they look.
Tools you may need: screwdriver, multimeter, flashlight
Safety warning: Disconnect power before opening any panels or touching internal components.
Start with a full reset. Unplug the refrigerator or turn off the dedicated breaker for 15 to 30 minutes, then restore power and monitor the display. If Error Code 24 disappears and cooling returns to normal, the issue may have been a temporary control glitch. If the code comes back, continue with internal inspection.
Check for frost buildup behind the freezer evaporator cover. Remove shelves or bins as needed, then take off the interior rear panel and inspect the evaporator coil area with a flashlight. Heavy ice accumulation usually confirms a defrost failure, and you may also notice the evaporator fan blocked by frost. If the panel is frozen in place, do not force it; manually defrost the compartment first and then continue.
Test the defrost heater for continuity with a multimeter. Disconnect the heater connector and measure resistance across the heater terminals; an open reading usually means the heater has failed and must be replaced. While you are there, inspect the heater casing and nearby connectors for burn marks, melted insulation, or moisture damage.
Inspect the defrost sensor, thermistor, and thermal fuse. The thermistor should not be physically cracked, waterlogged, or disconnected, and its resistance should change predictably with temperature. The thermal fuse should show continuity; if it is open, replace it and inspect the heater circuit carefully for the reason it overheated. If you are not comfortable interpreting thermistor values, that is a good point to call a professional.
Examine the wiring harness from the evaporator section to the cabinet connector and main control board. Look for pinched wires, corroded terminals, loose plugs, or broken conductors near bends and clips. Use the multimeter to verify continuity through the heater and sensor circuits. Repair damaged wiring only with proper connectors and insulation rated for appliance use.
After replacing any failed component, fully defrost the evaporator if ice buildup is still present. Reassemble the cover, restore power, and allow the refrigerator several hours to stabilize. If airflow improves and the code does not return, the repair was successful. If the evaporator refreezes quickly or the display shows Error Code 24 again, move to the final diagnostic step.
Check the main control board and call a professional if needed. If all field components test good but the board is not sending voltage to the defrost heater or is misreading the thermistor circuit, the PCB may need replacement. Because board diagnosis can involve live voltage checks and electronic testing around relays and capacitors, this is usually the point where professional service is the safest choice.
Yes, you can try a reset first by unplugging the refrigerator or switching off the breaker for 15 to 30 minutes. This may clear a temporary PCB fault, but if the code returns, the refrigerator likely has a real defrost circuit problem that needs testing with a multimeter.
It is not usually an immediate electrical emergency, but it should not be ignored. A failed defrost system can cause heavy frost buildup, blocked airflow, warmer food temperatures, and strain on the evaporator fan and compressor. Fixing it early helps prevent food spoilage and additional component damage.
The most common failure is the defrost heater circuit, including the heater itself, the thermal fuse, or the defrost sensor. In many service calls, one of these parts tests open or out of range. Wiring harness issues are also common in damp evaporator areas.
The total cost depends on which part has failed and whether you do the labor yourself. A simple sensor, fuse, or heater repair is usually much less expensive than replacing the main control board. If a technician must diagnose wiring or PCB issues, labor can make the total noticeably higher.
You can sometimes use it short term, but performance often gets worse as frost builds up on the evaporator. Cooling may become uneven, the fan can get noisy, and freezer temperatures may rise. It is better to address the issue quickly rather than waiting for a full loss of airflow.
Call a professional if you find heavy ice but cannot safely remove the evaporator cover, if the thermistor readings are unclear, or if all components test good and you suspect a PCB failure. You should also stop and get service if live voltage testing is required or if wiring damage extends into the cabinet.
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