Samsung Refrigerator Thermistor Replacement - Signs & How-To

Samsung Refrigerator Thermistor Replacement — What This Part Does

A Samsung refrigerator thermistor is an NTC temperature sensor that lets the main control board read compartment or evaporator temperature. The control uses those readings to manage cooling cycles and defrost timing. When a thermistor drifts, breaks electrically, or loses contact with the surface it monitors, the board gets out-of-range or nonsense data and can’t run the compressor and defrost logic correctly.

Thermistors fail because the resistance element degrades over time, wiring corrodes or breaks at the connector, or the sensor gets knocked out of position so it no longer touches the cold tube or senses the right airstream. Ice buildup or poor airflow can also create symptoms that look like a bad sensor, but if testing shows resistance clearly outside spec or an open or short circuit, replacement is the fix.

Jump to Replacement Steps

Signs It Needs Replacing

• Compartment too warm or too cold despite thermostat setting The control board makes wrong cooling decisions because it’s reading an incorrect temperature from the failed thermistor.
• Compressor runs continuously or cycles too often A sensor showing warmer than actual temp tells the board to keep cooling, or a sensor showing colder than actual causes rapid on-off cycling.
• Display shows a temperature sensor error code Samsung units throw fault codes when a thermistor signal is open, shorted, or out of the expected range.
• Excessive frost or ice buildup in freezer Bad defrost-sensor readings prevent the board from ending defrost at the right temperature, leading to incomplete melts or runaway cooling.
• Inconsistent or erratic temperature swings day to day Intermittent wiring faults or a thermistor drifting in and out of range cause unstable compartment temps even when the compressor works.
• Food spoiling faster than normal or freezing in the fridge section The control can’t hold set point when it’s getting bogus feedback from one or more temperature sensors.

How to Replace It

1. Unplug the refrigerator from the wall to kill all power before you start.
2. Remove food, shelves, drawers, and any interior covers or panels blocking access to the thermistor location (Samsung units may have sensors in the fridge compartment, freezer compartment, on the evaporator coil, or near the ambient air inlet).
3. Locate the suspect thermistor by tracing the wiring from the control board or by finding the small sensor clipped to a tube or mounted in the airstream (consult your model’s service sheet or wiring diagram if you have multiple sensors).
4. Disconnect the thermistor connector and inspect the harness and plug for corrosion, damaged pins, or broken wires.
5. Test the old thermistor with a multimeter set to ohms: at room temperature a typical Samsung sensor reads around 5 kΩ, and in ice water around 16.3 kΩ (replace if room-temp resistance is off by more than 5 percent, or if you see an open or short).
6. If the sensor tests bad, pull it from its clip or mounting bracket (note the exact position and orientation so the new one senses the same spot).
7. Install the new thermistor in the same clip and location, making sure it contacts the evaporator tube or sits in the airstream exactly as the original did.
8. Plug the new sensor connector back into the harness, tuck and route wiring so it won’t get pinched or rubbed by moving parts or covers.
9. Reinstall all panels, shelves, and drawers, plug the refrigerator back in, and monitor compartment temperatures and compressor cycles over the next 24 hours to confirm stable operation and no error codes.

The Part You Need

Related Error Codes

If this part is failing you may also see one of these codes:

• Samsung Refrigerator 1E error code
• Samsung Refrigerator 21E error code
• Samsung Refrigerator 22E error code
• Samsung Refrigerator 25E error code
• Samsung Refrigerator 2E error code
• Samsung Refrigerator 33E error code
• Samsung Refrigerator 39E error code
• Samsung Refrigerator 4E error code
• Samsung Refrigerator 5E error code
• Samsung Refrigerator 88 error code

When to Call a Pro

If you see multiple sensor codes at once, if the new thermistor still reads out of range after replacement, or if you’re not confident identifying which of several sensors is bad, call a tech with a service manual and diagnostic mode access. Also get help if the wiring harness is damaged behind interior walls or if you suspect a failed main control board rather than just the sensor. Samsung refrigerators often have three or more thermistors, and misdiagnosing which one is at fault wastes time and parts.