If your Frigidaire refrigerator is not keeping the right temperature, the thermistor might be the problem. This small part helps the fridge maintain proper cooling. When it fails, temperatures can go too high or too low, which may lead to spoiled food or frost buildup on the evaporator coils.
Follow the guide below to replace the thermistor and restore your refrigerator’s normal function.
Quick diagnosis table
The thermistor sits behind the control housing on the ceiling of the fridge, so have the nut driver ready.
| Symptom detail | Likely cause | What to check | Fix or part |
|---|---|---|---|
| Fridge too warm or too cold | Failed thermistor | Compare set temperature to actual | Replace thermistor |
| Frost building on evaporator coils | Thermistor mismanaging defrost | Look for frost on coils | Replace thermistor |
| Uneven temperature between compartments | Bad temperature readings to board | Check both compartments | Replace thermistor |
| Cooling cycle runs constantly or rarely | Control board getting wrong readings | Note how often compressor cycles | Replace thermistor |
| Thermistor fails soon after repair | Loose harness or wrong part | Check harness connection and part match | Use matching Frigidaire thermistor |
Why the Thermistor Matters
The thermistor is a temperature sensor that helps the control board know when to cool and when to stop. A broken thermistor can affect how well the fridge runs:
- Helps regulate the cooling cycle to avoid overcooling or undercooling
- Sends temperature readings to the control board for efficient operation
- Helps manage when the defrost cycle activates
- Supports even temperature control across the fridge and freezer compartments
- Reduces energy waste by helping the fridge work only when needed
Common Causes of Thermistor Failure
Thermistors can fail for many reasons. Understanding the causes can help prevent future problems:
- Normal wear and tear over time
- Loose or broken wiring connections
- Exposure to excess moisture inside the fridge
- Damage during previous repairs or maintenance
- Electrical surges or power issues
- Use of incompatible replacement parts in past repairs
What You’ll Need
Get these tools and parts ready before starting:
- 1/4 inch nut driver
- Replacement thermistor that matches your specific Frigidaire model
Safety Tips Before You Start
Working on appliances at home requires careful preparation. Keep these safety tips in mind:
- Always unplug the refrigerator or turn off the power at the circuit breaker to avoid electric shock
- Turn off the water supply if your fridge is connected to a water line
- Place towels nearby to absorb any leftover water when removing parts
- Allow the fridge to warm up if it has been running recently so you do not touch very cold parts
- Use insulated gloves to protect your hands from sharp edges inside the fridge
- Keep your hands dry and work on a dry surface
- Use bright lighting to help you see small parts and wire connections
- Clear the work area of tools, clutter, children, and pets
- Do not force parts while removing or installing them. Gentle pressure helps avoid damage
- If you need to work with wires, use a non-metal tool or wear insulated gloves
- Safety glasses or a dust mask can help if you expect debris inside the unit
- Check your refrigerator’s user manual for any model-specific safety steps or instructions
How to Replace the Thermistor in a Frigidaire Refrigerator
Follow these steps to remove the old thermistor and install a new one to help your fridge maintain the right temperature.
Unplug and Access the Thermistor
- Turn off the refrigerator and unplug it from the power outlet
- Remove the water filter from its compartment
- Remove the three 1/4-inch screws under the control panel (they are recessed into the panel)
- At the top back of the refrigerator, remove the 1/4-inch screw on the right side behind the filter area
- Drop the cover down carefully after removing the screw
- On the left side, remove the two recessed 1/4-inch screws from the side cover
- Lower the control housing to access the thermistor on the upper left side
Remove the Old Thermistor
- Pull the control housing forward to give space
- Remove the damper to reach the thermistor
- Disconnect the thermistor harness
- Remove the thermistor from its position
Install the New Thermistor
- Connect the new thermistor to the wiring harness
- Attach the thermistor to the damper
- Reinstall the damper into the control housing
- Push the control housing back into place on the ceiling of the refrigerator
- Reinstall the three 1/4-inch screws to secure the housing
- Insert the two 1/4-inch screws on the left side panel at the top
- Replace the single 1/4-inch screw behind the filter area
- Put the cover back over the tubing
- Install the final 1/4-inch screw to secure the tubing cover
Related guides
- Fridge Leaking Water Inside? Causes and How to Fix It
- DIY Guide: Replacing the Cutter Grid in Your Whirlpool Ice Machine
Brief Recap
Now that you know what signs to look for and how to handle the replacement, you’re better prepared to take action if it happens again. Having the right tools, a compatible thermistor, and a safe workspace can make the job easier from start to finish. Keep an eye on your fridge’s performance in the days after the repair, and always listen for any unusual noises or temperature swings that may need attention. Taking quick steps like this can help keep your appliance in great shape for the long run.
With the cause confirmed, order the refrigerator thermistor parts for your exact model and keep the old part until the repair has passed a full cycle.
