What is a sealed system?
Your refrigerator’s cooling system, also known as the refrigeration sealed system, is responsible for keeping your fridge at the proper, 
designated temperature. It’s a continuous process that, when halted, causes your refrigerator to lose it’s cool. A refrigerator that can’t stay cold can cause you a ton of problems.
There are a variety of issues that can cause your fridge’s sealed system to malfunction, including an overheated system, mechanical wear and tear, system leaks, or unwanted moisture entering the system. The sealed system is made up of a variety of components, any of which could break down due to age, misuse, or overworking. Each component has a specific part to play in maintaining the continuous thermodynamic process that cools your home refrigerator. Of all the appliance repair items you may have to take care of, sealed systems are among the most popular depending on the brand of your refrigerator.
How does a seal system work?
Your refrigerator’s sealed system sends refrigerant (typically Freon or Puron) through a continuous loop that heats and cools the refrigerant while turning it from a gas to a liquid and then back to a gas repeatedly. The sealed system essentially pulls out warm air, leaving behind cold air that is used to cool your fridge.
There are four main stages to this process that involve the compressor, the condenser, the expansion valve, and the evaporator.
A problem could arise at any of these stages. How will I know if there’s a problem with my sealed system?
The first obvious sign that your sealed system isn’t running properly (or running at all) is that your refrigerator will feel warm or your freezer 
will be above the freezing point.
You can also keep an ear out to listen for how often you hear the system running/humming. It is normal for the system to turn on and off as needed to maintain the proper temperature for your fridge, but if you hear it constantly working hard, or conversely, not running at all - it’s time to call a refrigerator sealed system specialist.
What happens during a sealed system diagnosis?
The first step the AAA Appliance team will take to determine if your refrigerator’s temperature problem stems from the sealed system is to measure the temperature of the condenser coils - the condenser coils on a sealed system that is running properly will measure roughly 30 degrees above ambient temperature of the room. If this is drastically over or under temperature, we know there is a problem with the sealed system. From there, a AAA refrigerator cooling system specialist will determine the root of the problem inside the sealed system and get you back onto the path towards a cold fridge!
Don’t wait until it’s too late to fix your fridge. AAA is the leader in refrigerator repair in St. Louis and St. Charles, MO.