Sub-Zero is considered the crรจme de la crรจme of refrigeration. While most factories test two or three units per manufacturing run, each refrigerator manufactured by Sub-Zero goes through careful inspection before being cleared to leave the factory. Their dedication to reliability and continuity throughout every model is another reason why they remain an industry leader. No matter the size or capacity, each Sub-Zero refrigerator is equipped with the latest features in refrigeration technology. 


It is clear why Sub-Zero continues to be the choice of professional chefs and experienced home cooks the world over. But even when it comes to these brilliantly designed and expertly equipped pieces of machinery, they too can malfunction from time to time. 

Have you noticed that your Sub-Zero refrigerator is running a bit warm? Is food spoiling more rapidly? Are you starting to see condensation on the inside of your refrigerator and are concerned that it isnโ€™t just the warmer weather that had your refrigerator running warm? If any of this is sounding familiar to you, we took the liberty of putting together a quick Sub-Zero troubleshooting guide to help you fix your refrigerator if it is running on the warmer side. 

 Warm Sub-Zero Refrigerator Troubleshooting Guide

There are some obvious and not-so-obvious indicators that there is a temperature problem in your Sub-Refrigerator. These troubleshooting exercises may help remedy the problem. If not, it may be necessary to contact a Sub-Zero certified repair company that can come to your home and professionally service your Sub-Zero refrigerator. 

Common signs that your Sub-Zero refrigerator is running warm: 

  • Noticeably warmer temperature inside your refrigerator 
  • High temperatures reported on your Sub-Zero internal temperature gauge 
  • Sub-Zero refrigerator wonโ€™t hold a set temperature and continues to fluctuate
  • The unit has trouble keeping food cool in the warmer weather months
  • Food spoils before the expiration date 

Clearly, it doesnโ€™t take much to see that your refrigerator is running warm. But before you go calling a refrigerator repair company, it is best to go through the easy fixes first. 

  • Problem 1: Dirty Condenser Coils 

Solution: Your refrigeratorโ€™s condenser coils are located on the underside of your Sub-Zero. Condenser coils are responsible for getting rid of heat. If these coils become dirty or have a considerable amount of grime on them, chances are your refrigerator is having to work harder just to function. If the condenser coils remain dirty, your Sub-Zero will continue to slow down and be less efficient. Check the condenser coils, looking for any grime, debris or dust. If you feel like you can easily access the condenser coils for proper cleaning, then go for it. First, make sure your refrigerator is turned off and unplugged. Then proceed to clean the coils with a warm damp rag. Remember to be mindful of the delicate nature of condenser coils. If that all sounds like too much, or you canโ€™t reach the condenser coils since the weight of most Sub-Zero refrigerators is significant, it may be wise to contact a professional Sub-Zero repair company to safely clean the condenser coils without causing further harm or damage to your appliance.  

  • Problem 2: The Fan Motor in the Condenser

Solution: The function of your condenser fan is to draw cool air in and distribute it over the compressor. Your refrigerator will be unable to cool itself down properly if the condenser fan motor is not working correctly. Fixing a condenser fan can get a little tricky though. To find out if the fan motor is malfunctioning, first check the fan for obstructions. Try moving the blade manually. If you notice that the blade is not moving with ease, you have a situation where the condenser fan motor needs replacing. Sub-Zero refrigerators have excellent warranties. All it would take is a quick phone call to a Sub-Zero certified maintenance specialist to confirm that it is indeed your condenser fan motor and replace it. 

  • Problem 3: Temperature Control Thermostat 

Solution: Every Sub-Zero refrigerator comes with the latest in temperature control tech. Sometimes when your refrigeratorโ€™s thermostat isnโ€™t working, it could prevent the rest of the refrigerator from operating properly. Your thermostat is responsible for orchestrating what voltage is distributed to the compressor, evaporator fan motor and condenser fan motor. Without it, the rest of the refrigerator could not be receiving the right information to signal them to turn on. To check to see if your thermostat is defective, try turning your Sub-Zero thermostat from the coolest setting to the warmest setting. You should hear something click on and the fans should come on. If nothing comes on, it is time to have a certified Sub-Zero technician come take a look at your refrigerator. 

  • Problem 4: Defective Start Relay 

Solution: Your start relay is what helps trigger the compressor to turn on. This is especially important because your refrigerator relies on the compressor to cool all of the working parts and keep it running smoothly. Youโ€™ll have to use a multimeter to confirm if it is defective. Not everyone has a multimeter laying around the house, but if you do, use it to test for continuity between the run and start terminal sockets. If you see any deviations or the start relay has a burnt odor, it is time to replace it. Again, contacting a professional refrigerator repair company is your best bet. Preferably one that is certified to work on Sub-Zero refrigerators. 

  • Problem 5: Compressor Isnโ€™t Working 

Solution: Your refrigeratorโ€™s compressor is extremely important. If your compressor is malfunctioning your refrigerator wonโ€™t be able to cool anything, and will stop working altogether. Thankfully, with Sub-Zero refrigerators it is awfully rare. Before you go and pay to have the compressor replaced, it is best to go down the list we provided above. If you do determine that the compressor is broken, absolutely call a trusted Sub-Zero technician. 

Who to Call If Your Sub-Zero Refrigerator Isnโ€™t Working Properly 

Even with all of the troubleshooting help available online, you still may need a certified Sub-Zero technician to come and inspect your unit. Not every problem is easily pinpointed as most parts are reliant on the other working to provide superior Sub-Zero cooling technology. When in doubt, call Wilshire Refrigeration. We have a team of licensed Sub-Zero repair technicians that can be at your home in an instant to find the existing problem and offer affordable solutions. 

Wilshire Refrigeration is the only factory certified service provider for Sub-Zero refrigerators and appliances in Los Angeles and surrounding areas. If you need to get your Sub-Zero serviced, weโ€™re the people to call. 800.427.3653