Refrigerator Compressor Explanation: Comprehensive 411 Guide

Want a comprehensive refrigerator compressor explanation? This article is your one-stop guide to all things refrigerator compressors.

Refrigerator Compressor Explanation
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Refrigerator Compressor Explanation

The refrigerator compressor is a motorized device encased in a usually metallic housing situated at the rear bottom of your refrigerator. It serves as the ‘engine’ that drives the refrigeration cycle. But what does that mean?

The primary role of the compressor is to convert low-pressure gas from the fridge into high-pressure gas. This transformation is essential because the high-pressure gas aids in the refrigeration process, which keeps your food and beverages cold. Without a functioning compressor, your refrigerator essentially becomes a storage cabinet at room temperature.

In essence, the compressor is the linchpin of your refrigerator’s cooling system. If it fails, the whole system grinds to a halt. That’s why it’s often termed the ‘heart’ of the refrigerator.

Components of a Refrigerator Compressor

The refrigerator compressor isn’t just a single unit but is made up of several parts that work together to compress the refrigerant and facilitate the cooling process. Let’s break down these components:

Electric Motor

The electric motor is the driving force behind the compressor. When you plug your refrigerator into an electrical outlet, the motor gets the energy to run. It is responsible for spinning the crankshaft, which is a fundamental step in the compression process. This motor generally operates at a high RPM (Revolutions Per Minute) to ensure efficient compression.

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Connected to the electric motor, the crankshaft translates rotational motion into a reciprocating (back-and-forth) motion. It is the crankshaft’s movement that allows the pistons to move, initiating the next phase of the refrigeration cycle.


Pistons are cylindrical components that move up and down within cylinder casings. Their motion is what actually compresses the low-pressure gas into high-pressure gas. Each upward stroke of a piston reduces the volume of the gas, increasing its pressure.


The cylinder is the chamber where the piston moves up and down. It’s a tightly sealed area to prevent any leakage of refrigerant. The walls of the cylinder must be smooth and durable to minimize friction as the piston moves.

Suction and Discharge Valves

These valves control the flow of the refrigerant gas. The suction valve allows the low-pressure gas to enter the cylinder, while the discharge valve lets out the high-pressure gas once it’s been compressed. They operate in a one-way fashion to ensure that gas flows in the intended direction.

Refrigerant Lines

These are the tubes or pipes through which the refrigerant flows. The suction line carries the low-pressure gas into the compressor, and the discharge line takes the high-pressure gas toward the condenser coils. They are typically made of copper for efficient heat transfer.

Seals and Gaskets

These are materials made from rubber or silicone, placed between joints and connections to prevent any refrigerant leakage. A seal or gasket failure can lead to a loss of refrigerant, which would hamper the cooling process.


The housing contains all the above-mentioned components. It is often made of sturdy materials like metal to protect the internal parts from external elements, including moisture and dust.

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Electrical Connections

Last but not least, the electrical connections ensure that the motor gets the necessary power to function. These usually include a set of wires and possibly a capacitor that helps the motor start up.

How Does a Refrigerator Compressor Work?

Understanding how a refrigerator compressor works can seem complex, but it boils down to a straightforward cycle involving a few key steps:

Compression Phase: The compressor starts by sucking in low-pressure gas from the refrigerator’s interior. Through mechanical action, this gas is compressed into a high-pressure and high-temperature gas. This action is what gives the compressor its name.

Condensation Phase: This high-pressure gas is then moved through a series of coils—known as the condenser coils—usually located at the back or underside of the fridge. Here, the gas releases its heat into the surrounding environment and condenses into a high-pressure liquid.

Expansion Phase: The liquid refrigerant flows through a constriction—often a tiny hole or an expansion valve. This action converts it into a low-pressure, low-temperature liquid.

Evaporation Phase: This cold, low-pressure liquid enters another set of coils—the evaporator coils—inside the fridge. The liquid absorbs heat from the interior of the fridge and evaporates, returning to a low-pressure gas form.

This cycle repeats, thereby maintaining the internal temperature of your refrigerator at the desired level.

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Signs of a Malfunctioning Compressor

A faulty compressor is a serious issue that can affect your refrigerator’s cooling efficiency. Here are signs that your compressor might not be working properly:

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Constant Operation: A healthy compressor turns off when the fridge reaches the desired temperature. If your fridge runs non-stop, it may mean the compressor is struggling to maintain temperature.

Inadequate Cooling: If the interior of your fridge doesn’t seem as cold as it should be, the compressor might be failing.

Unusual Noises: If you hear buzzing or clicking sounds coming from the back of your fridge, this could indicate compressor issues.

Water Leakage: While not directly a compressor issue, pooling water could mean the entire cooling system is compromised, which often implicates the compressor.

If you notice any of these signs, consult a certified technician immediately for a thorough diagnosis and repair.

How to Maintain Your Compressor

Regular maintenance is crucial for extending your compressor’s lifespan. Here are some proven tips:

Clean the Condenser Coils: Dirt and dust on the condenser coils force the compressor to work harder, using more energy and risking breakdown. Use a coil brush or a vacuum cleaner to clean the coils every six months.

You can use this Vanitek Dryer Vent Cleaner Lint Brush listed on Amazon to clean the condenser coils.

Ensure Adequate Ventilation: Compressors need space for efficient operation. Make sure there’s at least a one to two-inch gap between the fridge and the wall for adequate airflow.

Avoid Overloading the Fridge: An overloaded fridge can restrict airflow and make the compressor work harder. Always allow for space between items for effective cooling.