How to Diagnose Your 500/600 Series Sub-Zero Refrigerator

Well-made and reliable 500 Series Sub-Zero refrigerators are known to last for many decades until you get to experience the first signs of a problem.

However, even if your Sub-Zero refrigerator stops cooling, it does not mean you have to start looking for a new fridge right away – most of the time, a simple fix will rejuvenate your appliance and let you enjoy high-quality refrigeration for many more years!

‍MAKE SURE TO UNPLUG YOUR APPLIANCE BEFORE YOU START DISASSEMBLING OR REPAIRING IT. ADDITIONALLY, KEEP IN MIND THAT IT MAY TAKE UP TO 24 HOURS FOR A PROPERLY WORKING REFRIGERATOR TO REACH THE TARGET TEMPERATURE.

Step 1. Test the outlet!

The first thing you should do before performing any further diagnostics is to check the power outlet for proper voltage. Unfortunately, this kind of problem is pretty standard, and you would be surprised how often our technicians come to the customer’s house only to discover that the source of the problem is a tripped circuit breaker. Even if the breaker is not tripped, it’s important to remember that insufficient voltage would significantly reduce the performance of your appliance, even if your Sub-Zero refrigerator is perfectly functional.

Step 2. Make sure the door does not leak cool air.

Carefully examine the door seal and ensure it is not damaged or cracked, or closed snuggly. Even a tiny air leak could result in the hot air getting inside the refrigerator or freezer, making it nearly impossible to drop the temperature to the required level.

Step 3. Clean the condenser.

It is recommended to carefully clean the condenser coil of your refrigerator once or twice a year to improve the power efficiency – a dusty condenser will make it significantly harder for your refrigerator to dissipate heat. It will undoubtedly increase the cycle length and, as a result, its power consumption. In most built-in and integrated 500 Series Sub-Zero refrigerators, the condenser can be found above or below the fridge. You can access it by lifting the front panel or removing it entirely. Depending on its position, you can choose whether to clean the coil manually with a brush or to use compressed air or a vacuum – remember, however, that you risk spreading the dust all over the kitchen.

Step 4. Make sure the fans are running.

Sub-Zero refrigerators have at least two fans – one for each coil. Evaporator and condenser fans significantly improve the performance of your appliance – and even a single malfunctioning fan will result in a significant drop in performance. It could potentially prevent your appliance from reaching the target temperature. A malfunctioning motor is a common cause of fan failure. However, examining and testing the wiring with the multimeter would also be a good idea.

Step 5. Test the control board and thermostat.

A faulty main board and thermostat can prevent the refrigerator from running the cooling cycle efficiently. Even though primary board diagnostic is a difficult task, both of these parts can be replaced in case you successfully find the source of the problem.

Step 6. Test the compressor.

We recommend you test your compressor. However, you would need a multimeter and a basic understanding of your refrigerator wiring. And don’t forget to unplug your refrigerator before disassembling and testing it! In most Sub-Zero 500 Series fridges, the compressor is behind a grill at the top part of the refrigerator. Carefully unhinge and remove the grill and then the cover. Depending on the model, you may see two compressors – for the freezer and the refrigerator. Test the compressor pins for connectivity. You may have to replace the compressor in case you find damaged wiring.

Step 7. Measure the refrigerant pressure.

Unfortunately, accessing the sealed system and measuring the coolant pressure requires specialized equipment. However, if the pressure is insufficient, you can look for a gas leak within the sealed system. We recommend checking junctions on the tubes, especially the capillary tubes, since they are most subjected to this kind of leak. We recommend using a gas leak detector spray. However, you can also use soap or WD-40. The exact repair depends on what part needs to be replaced.

If you need professional appliance repair service in the area, look no further than Appliance Cowboys! Our highly skilled team of expert technicians, equipped with years of experience in the industry, is ready and prepared to tackle any job, no matter the complexity. We take pride in our dedication to ensuring that your appliances function smoothly and optimize for peak performance so that you can enjoy the utmost convenience.

With our comprehensive knowledge of various appliance brands and models and our meticulous attention to detail, you can trust us to deliver top-notch service that consistently exceeds your expectations. Our friendly and professional technicians will go above and beyond to ensure that your appliances are repaired efficiently and effectively, leaving you with the peace of mind that comes with a perfectly functioning Sub Zero refrigerator.

Don’t wait! Book an appointment with us today and experience the convenience and satisfaction of having your appliances expertly repaired by the Appliance Cowboys. You won’t be disappointed!