How Does a Refrigerator Compressor Work?

Your refrigerator quietly keeps food fresh day in and day out, but have you ever wondered how it actually works? At the core of every refrigerator’s cooling mechanism lies the compressor—the heart of the system that drives the cooling process. Without it, there’d be no cool air to preserve your groceries. Understanding how a refrigerator compressor works not only sheds light on the technology behind your fridge but also helps you troubleshoot common issues and better appreciate this essential appliance.

In this article, we’ll explore the function, components, and process of the refrigerator compressor, highlighting how it plays a vital role in keeping your fridge at just the right temperature.

What Is a Refrigerator Compressor?

A refrigerator compressor is a pump that moves refrigerant through the system, controlling temperature by compressing, heating, and circulating the refrigerant. It sits at the bottom or back of the refrigerator and operates with the help of other key components, including the evaporator and condenser.

The compressor’s role is to increase the refrigerant’s pressure and temperature, setting the stage for the cooling cycle that keeps your food fresh.

Simply put, the compressor compresses refrigerant gas and circulates it throughout the refrigerator sealed cooling system to help create a cooling effect inside.

The Role of the Compressor in the Cooling Process

To understand how the compressor works, let’s take a look at the entire cooling cycle. The refrigerator cooling system consists of four main parts: the compressor, condenser coils, expansion valve, and evaporator coils. Here’s how these parts work together in a continuous cycle:

• Compression: The compressor begins by compressing the refrigerant gas, a low-pressure vapor, turning it into a high-pressure, high-temperature gas. This compression increases both the temperature and pressure of the refrigerant.
• Condensation: The high-pressure gas then flows into the condenser coils, where it releases its heat to the surrounding environment. As the refrigerant cools, it condenses into a high-pressure liquid.
• Expansion: This high-pressure liquid then passes through an expansion valve, where it is allowed to expand into a low-pressure, low-temperature liquid.
• Evaporation: The cold liquid refrigerant then flows through the evaporator coils inside the refrigerator. As it evaporates, it absorbs heat from the fridge’s interior, cooling down the evaporator fins and the inside of the refrigerator.

This cycle repeats continuously, with the compressor pumping the refrigerant through the system, allowing it to keep the refrigerator interior at a stable, cool temperature.

How Does the Compressor Compress Refrigerant?

The compressor uses a piston or rotary mechanism to compress the refrigerant gas. Most household refrigerators use one of two types of compressors:

• Reciprocating Compressor: A piston compresses the refrigerant in a back-and-forth motion. When the piston moves down, it pulls refrigerant in; when it moves up, it compresses and pushes the refrigerant out.
• Rotary Compressor: A rotor spins inside a chamber, trapping and compressing the refrigerant. As the rotor turns, it continuously compresses refrigerant gas without stopping, making rotary compressors more energy-efficient and quieter.

These mechanisms allow the compressor to increase the pressure and temperature of the refrigerant, preparing it for cooling down in the condenser coils.

Why the Compressor Is Essential for Cooling

The compressor is vital because it provides the energy needed to push the refrigerant through the cooling system. By pressurizing and heating the refrigerant, the compressor initiates the temperature change cycle. Without the compressor, the refrigerant would remain in a low-pressure state, unable to circulate or absorb heat from inside the refrigerator.

Moreover, the compressor helps regulate the cooling cycles in the refrigerator, turning on and off as needed to maintain a steady temperature. When the refrigerator reaches its ideal temperature, the compressor stops. Once the temperature rises, it kicks back on to restart the cooling process.

Common Issues with Refrigerator Compressors

Compressors are durable but can develop issues over time due to wear and tear, mechanical failure, or refrigerant leaks. Here are some common compressor problems and how to troubleshoot them:

Overheating

Compressors can overheat if the condenser coils are dirty, obstructed, or if the compressor is running too frequently. Cleaning the coils and ensuring proper ventilation can often resolve this issue.

Here’s a video that shows how to clean refrigerator condenser coils:

Excessive Noise

A noisy compressor can be due to worn-out components or a failing compressor pump. If it’s noticeably louder than usual, it may need servicing or replacement.

Schedule refrigerator repair service when your compressor begins making loud noises.

Failure to Start

If the compressor doesn’t turn on, it could be due to a faulty start relay or a number of other problems. This video from Sears PartsDirect shows how to troubleshoot problems with your refrigerator’s compressor.

If you’re unable to fix the compressor starting problem on your own, schedule refrigerator repair service and we’ll send a Sears Home Services technician to your home to resolve the issue.

Refrigerant Leaks

A loss of refrigerant due to leaks can cause the compressor to work harder and eventually fail. When the compressor runs nearly constantly but the refrigerator and freezer sections don’t cool well, the sealed system may be low on refrigerant due to leaks.

For refrigerant and sealed system issues, it’s best to contact a qualified technician. Only service providers certified to handle refrigerants are allowed to work on the compressor and sealed system unit.

Tips for Maintaining Your Refrigerator Compressor

To keep your refrigerator compressor in optimal condition, follow these maintenance tips:

• Clean the Condenser Coils every six months to prevent dust buildup, which can lead to overheating.
• Ensure Proper Ventilation by keeping space around the refrigerator for airflow.
• Check Door Seals regularly to make sure they’re tight and not allowing warm air into the refrigerator.
• Avoid Overloading the Refrigerator to prevent overworking the compressor.
• Schedule annual professional refrigerator maintenance to help keep your compressor and fridge operating efficiently and lasting longer.

Proper cleaning, care and maintenance will help your compressor and fridge run smoothly for many years to come.