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refrigerator won't cool

Why Is My Sub-Zero Refrigerator Not Cooling?



Sub-Zero refrigeration technology has long been considered superior among high-end brands. So much so that any cooling issues can usually be fixed with simple maintenance or a minor adjustment. Why is my Sub-Zero refrigerator not cooling? The temperature may be set incorrectly, requiring a quick change on the control panel or temperature dial. Troubleshoot Sub-Zero refrigerator temperature problems with these common causes.

5 Reasons For a Sub-Zero Refrigerator Not Cooling

From incorrect temperature settings to a damaged door gasket, the most likely reasons for a Sub-Zero refrigerator not cooling have a DIY fix. Here’s how to pinpoint the problem and the right solution.

#1. Incorrect Sub-Zero Refrigerator Temperature

Sub-Zero refrigerators cool optimally when set at a particular temperature or within a specific range. Inadvertent changes to the control panel or temperature dial can result in a Sub-Zero refrigerator not keeping cold.

For refrigerators with an electronic control panel, Sub-Zero recommends a temperature setting of 38℉. The temperature can be raised or lowered by pressing the “warmer” or “cooler” buttons on the control panel. For those models with a temperature control dial, make sure the dial is set between 4 and 6 for optimal cooling.

#2. Refrigerator Was Recently Stocked With Food

Loading your refrigerator with a large number of groceries or warm food may increase the internal temperature. While it should cool down in a few hours, proper loading methods can better maintain the refrigerator’s internal temperature. 

Follow these loading tips to maintain cool refrigerator temperatures:

  • Leave adequate space between stored items so cool air can circulate. 
  • Avoid storing food in front of refrigerator vents so cool air can freely enter.
  • Allow warm items to come to room temperature before storing them in the refrigerator.
  • Make sure stored items don’t block the door from closing.

Sub-Zero refrigerator not cooling

#3. Refrigerator Doors Were Left Open

Doors that were inadvertently left open are one of the most common reasons a refrigerator won’t cool. Try to open doors for as short a time as possible when replacing and retrieving food. Always make sure the doors are completely closed after each use.

Your Sub-Zero Door Ajar Alarm would alert you if the doors were left open for more than 30-60 seconds. To enable this feature, press the “Alarm” key on the control panel. A bell icon should appear on the display, indicating that the alarm is enabled. 

#4. Sub-Zero Door Gasket is Dirty or Damaged

The rubber gasket along the door’s perimeter creates a tight seal when the door is closed. This enables cool air to stay inside the refrigerator and prevents warm, room temperature air from entering.

Your Sub-Zero refrigerator won’t get cold enough if the seal is compromised from damage or debris. Even small holes or tears can allow cool air to exit the refrigerator and warm air to enter, increasing the internal temperature. Inspect the gasket for dirty buildup or signs of damage. While a dirty gasket can be cleaned with a damp cloth to restore its seal, a damaged gasket must be replaced.

Sub-Zero refrigerator temperature problems

#5. Dirty Sub-Zero Condenser Coils

Lastly, dirty condenser coils are another common reason for a Sub-Zero refrigerator not cooling. These coils remove heat from the refrigerant that runs through them, providing cool air for the refrigerator. Coils that are coated in dust and dirt may not be able to cool the refrigerant, overworking the condenser and creating warmer temperatures. 

Cleaning the coils every 6 months can ensure that they operate properly and that the refrigerator maintains its temperature.

Follow these steps to perform a Sub-Zero condenser coil cleaning:

  • Turn off the refrigerator’s power.
  • Remove the Sub-Zero refrigerator grille.
  • Clean the coils with a vacuum’s soft bristle brush attachment.
  • Replace the grille.
  • Restore the refrigerator’s power.

Is your Sub-Zero refrigerator not cooling even after these troubleshooting tips? A  professional assessment may be the only way you and your refrigerator can keep your cool. Schedule your service with the Sub-Zero refrigerator repair experts at RD Appliance Service, Corp today!

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