How to Tell the Difference Between a Refrigerator Compressor Issue and a Starting Device Issue

How to Tell the Difference Between a Refrigerator Compressor Issue and a Starting Device Issue

When your refrigerator stops cooling, the problem may stem from either the compressor or the starting device. These components work together to circulate refrigerant and maintain the appliance’s cooling efficiency. Identifying the root cause of the issue can save you time, money, and unnecessary repairs. Here’s a guide to help you distinguish between a compressor issue and a starting device problem.

Step 1: Understand the Function of Each Component

  1. Compressor: The compressor is the heart of the refrigerator’s cooling system. It pumps refrigerant through the coils, enabling heat exchange that keeps your fridge cold.
  2. Starting Device: This component includes the start relay and overload protector, which help the compressor start running. If the starting device fails, the compressor may not turn on.

Step 2: Signs of a Compressor Issue

A faulty compressor can be more challenging to diagnose, but here are some common symptoms:

  1. No Cooling: If the compressor is not running, the refrigerator won’t cool at all.
  2. Constant Clicking: A faulty compressor may click on and off repeatedly as it tries (and fails) to start.
  3. Overheating: Touch the compressor; if it’s unusually hot, this could indicate an internal problem.
  4. Humming but Not Cooling: If the compressor runs but the fridge isn’t cooling, there could be an issue with the refrigerant or internal components.
  5. No Sound or Vibration: Compressors usually produce a low hum or vibration. A silent and non-vibrating compressor might be defective.

Step 3: Signs of a Starting Device Issue

Starting device problems are more common and often easier to fix. Look for these signs:

  1. Repetitive Clicking Noise: This indicates the start relay is trying to start the compressor but failing.
  2. Compressor Doesn’t Start: If the starting device is defective, the compressor won’t turn on.
  3. Burnt Smell or Physical Damage: A burnt smell or visible damage to the starting relay suggests it has failed.
  4. Intermittent Cooling: The fridge may cool sporadically if the starting device is struggling to activate the compressor.

Step 4: Perform a Diagnostic Test

1. Test the Starting Device

  • Step 1: Unplug the refrigerator for safety.
  • Step 2: Locate the starting device, typically attached to the side of the compressor.
  • Step 3: Remove the starting device and inspect it for damage or burning.
  • Step 4: Test the device with a multimeter to check for continuity.
    • Result: No continuity indicates the device is faulty and needs replacement.

2. Test the Compressor

  • Step 1: Keep the starting device removed.
  • Step 2: Use a multimeter to test the compressor's terminals for continuity:
    • Resistance Test: Place the multimeter probes on the terminals. You should get resistance readings between each pair of terminals.
    • Ground Test: Place one probe on a terminal and the other on the compressor casing. If there is continuity, the compressor is grounded and likely defective.
  • Result: If the compressor fails either test, it may need to be replaced.

Step 5: Troubleshooting Tips

  1. Replace the Starting Device First

    • Since starting devices are inexpensive and fail more often than compressors, it’s worth replacing the starting device first to see if it resolves the issue.

  2. Listen for Compressor Sounds

    • If the compressor runs after replacing the starting device, the problem was with the starting relay or overload protector.
    • If the compressor doesn’t start, it’s likely defective.

  3. Call a Professional

    • If you’re unsure of your diagnostic results or the compressor shows signs of failure, consult a professional technician. Compressor repairs can be complex and often require specialized tools.

When to Replace the Compressor

If the compressor is the root cause of the problem, replacing it may not always be cost-effective. Compressors are expensive, and labor costs can be high. For older refrigerators, it might be better to invest in a new appliance instead.

Conclusion

Distinguishing between a compressor issue and a starting device problem can be done with careful observation and simple diagnostic tools like a multimeter. In most cases, starting device failures are easier and less expensive to fix, so always test and replace the starting device first. If you suspect a compressor failure, consider consulting a professional or visiting a reliable appliance parts store like PRS Parts Inc. in Honolulu, Hawaii, for high-quality replacement parts and expert advice.

Image courtesy of Specialty Product Technologies - Joslyn Clark.

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