08/30/2026
This is the first in a multi-part series that will explain how appliances work, the pros and cons of each configuration, and the pros and cons of their various features.
First up: Fridges!
First, we need to understand how a fridge works.
Fridges don't work by pumping in cool air; instead, they pump out the heat from within.
One set of coils is called the evaporator coils. They are located within the freezer (FZ) compartment. They become very cold and absorb heat.
The refrigerant passes through the compressor and then reaches the condenser coils. The heat absorbed from the evaporator coils within the freezer compartment is released at the condenser coils. The condenser coils are either located at the back, bottom rear, or bottom of the fridge.
So the evaporator coils absorb heat, the compressor pumps the refrigerant through the sealed system, the condenser coils release this heat outside the fridge, and the refrigerant makes its way back to the evaporator coils, thus forming a closed loop.
Fans on both the evaporator and condenser coils move air through the coils to increase the rate of heat exchange.
Here is the interesting fact: in the vast majority of fridges, the freezer compartment is cooled via the evaporator coils, and then the evaporator fan moves the cold air into the fridge (FF) compartment.
Return air channels then bring warmer air from the fridge compartment back to the freezer compartment, and the process begins again.
That means we have yet another loop!
Now that we've learned how a fridge works, it can help us understand the various fridge configurations!
Fridge configurations are defined by the freezer compartment's location.
There are three basic configurations:
1.) Top-Mount (freezer on top)
2.) Bottom-Mount (freezer on bottom)
3.) Side-by-Side (SXS)
These are the pros and cons of each:
1.) Top-Mount:
Pros:
Since the freezer compartment is on top, cold air naturally sinks down to the fridge compartment because it's denser. Also, warmer air in the fridge compartment naturally rises back up to the freezer compartment.
This makes top-mount fridges more efficient since the fans and ducts aren't fighting gravity.
Cons:
Top-mounts can't have the convenient pull-out drawers that some bottom-mounts offer. It's harder to organize your food since you're dealing with only a shelf.
2.) Bottom-Mount:
Pros:
Many offer convenient pull-out drawers in the freezer compartment, and the fridge section can be offered with the French-door configuration (two doors that open away from each other).
Cons:
The cold air from the freezer compartment has to be forced upwards against gravity, and the warmer air from the fridge compartment also has to be forced downward. This results in a less efficient loop than top-mounts.
3.) Side-by-Side (SXS):
This is when the freezer compartment is on its own on the left side in a vertical configuration, and the fridge compartment is on the right in a similar setup.
The cold air is pushed upward in the freezer compartment and passes through a damper at the top where the two compartments join, works its way down the fridge compartment, passes through a vent at the bottom, and returns to the bottom of the freezer compartment. The airflow is therefore clockwise.
Pros:
Taller spaces make it easier to stack tall items. Tall vertical doors for a French-door-like configuration.
Cons:
Less efficient airflow because it fights gravity; the narrow freezer compartment can make storing and accessing food awkward.
And there you have it!
There are now newer configurations such as 4-door (4 evenly sized compartments with 2 on top and bottom), 5- and 6-door (horizontal pull-out drawers), but we will get into detail with these in the next posts!
Later, we will discuss dual-evaporator coils and even double-sealed system fridges, so stay tuned!