Quiet operation is just one of a Sub-Zero refrigerator’s superior qualities, making any loud noises that much more unusual. Why is my Sub-Zero refrigerator freezer loud? If the refrigerator noise stops when freezer door is closed, the freezer evaporator fan may have malfunctioned. Determine why your Sub-Zero refrigerator freezer is loud with these troubleshooting tips.
What To Do When Your Sub-Zero Refrigerator Freezer Is Loud
While evaporator fan issues are often the case when your Sub-Zero refrigerator freezer is loud, there may be other causes. However, before we troubleshoot abnormal sounds, it’s important to understand what sounds are part of normal operation.
Normal Sub-Zero Refrigerator Freezer Noises
As quiet as your Sub-Zero refrigerator freezer may be, some operating noise is to be expected.
The following sounds are part of normal Sub-Zero freezer operation and aren’t a cause for concern:
- Humming: A low Sub-Zero humming noise can be heard when the compressor and evaporator fan are operating normally.
- Sizzling and crackling: These brief sounds can be heard at various points in the defrost cycle when moisture drips on the defrost heater.
- Banging or crashing: A quick bang or crash may be heard when ice drops into the ice bin.
However, if your Sub-Zero refrigerator freezer makes noise when door is closed, but not open, an evaporator fan problem may be responsible. Here’s how to troubleshoot evaporator fan issues.
Is There a Buildup of Ice?
When your Sub-Zero refrigerator is loud with gurgling sounds, it’s usually an indicator that the fan is obstructed by ice. You may also notice a buildup of ice around the freezer’s rear panel, where the evaporator fan is located. To determine if the fan is icy, consult your user manual to determine how to remove the rear panel on your model freezer.
If ice is visible on or around the evaporator fan, Sub-Zero recommends manually defrosting the freezer to melt the ice. Some model refrigerators allow for manual defrosting of specific sections so the rest of the refrigerator can remain operational. Your user manual will specify if this is possible on your model refrigerator.
Faulty Evaporator Fan Motor
If the evaporator fan isn’t obstructed by ice you may still find your Sub-Zero refrigerator loud with knocking noises. These sounds often mean that the fan blades are encountering a different obstruction or are damaged. While the evaporator fan is accessible, look for any other obstructions that could prevent the blades from rotating and remove them. However, if the blade is damaged or the fan doesn’t turn easily by hand, it must be professionally replaced.
Is your Sub-Zero freezer noisy when door is closed even if the fan blades are working properly? It’s possible that the fan motor is faulty. When the fan motor fails, your Sub-Zero refrigerator’s normal humming noise will be much louder in volume when the door is closed. In this case, the fan motor must be replaced.
Compressor or Condenser Problems in Sub-Zero Refrigerator
If loud refrigerator noise is not attributable to the evaporator fan, then there is likely a compressor or condenser issue. In addition to loud noises, you may also notice your refrigerator is warm inside and not cooling adequately.
The following condenser or compressor problems may be at fault when your Sub-Zero refrigerator freezer is loud:
- Dirty condenser coils: These coils cool refrigerant so that cool air can be produced for the refrigerator. If they become coated in dust and dirt, the condenser may work harder and louder to cool the refrigerator. Consult your user manual to determine how to clean the condenser coils on your model refrigerator. Most can be found behind an upper grille and are easily vacuumed with a narrow hose attachment to remove dust and debris.
- Condenser fan malfunction: Like the evaporator fan, the condenser fan can suffer malfunctions and blockages that impair its function. When this happens, the condenser coils may not cool adequately. If the condenser fan is loud or not rotating properly, it must be replaced.
- Failing compressor: The compressor will also make a loud humming sound when it starts to fail. While it may continue to operate and cool the refrigerator, it should be professionally replaced as soon as possible.
The technicians at Caesar’s Appliance Sales & Service can perform any Sub-Zero refrigerator repair. Call or schedule your service online!