How to Test a Refrigerator Compressor: Step-by-Step Guide

Have you ever opened your fridge, only to find it’s not cooling as it should? One of the most common culprits behind poor refrigerator performance is a faulty compressor. Don’t worry; we’ve got you covered! In this article, we’ll dive into how to test your refrigerator compressor, spot the signs of trouble, and even fix it yourself. Let’s get started and save you a costly repair bill.

Signs Your Refrigerator Compressor Might Be Failing

When your refrigerator starts acting up, it’s not always obvious what’s wrong. You might notice warm food or a fridge that’s making unusual noises. But if you’re experiencing any of the following signs, it could be a red flag that your compressor is on its way out.

1. Unusual Noise or No Noise at All

The compressor in your fridge is responsible for circulating refrigerant to cool the air inside. When it’s working properly, it should make a gentle humming or buzzing sound. If you notice strange noises, like loud clicking, rattling, or no sound at all, that’s usually a sign that something’s wrong with the compressor or other related components.

A failing compressor can create an inconsistent buzzing sound or a continuous buzzing noise. Sometimes, the compressor may even get too hot to touch, and that can signal it’s struggling to do its job. Pay close attention to your fridge’s behavior when it comes to noise—it’s often the first sign of trouble.

2. Refrigerator Isn’t Cooling Properly

A common symptom of a bad compressor is poor cooling. If your fridge isn’t cold enough, but the freezer is working just fine, your compressor might be malfunctioning. The compressor helps maintain proper temperature levels, and when it’s on the fritz, your refrigerator will have trouble regulating its internal temperature.

In some cases, the fridge may feel slightly cold, but not to the degree it should. The freezer might seem fine, but your food and drinks might not be as cold as you expect. If the temperature is fluctuating or if the fridge isn’t cooling evenly, it’s a good idea to check the compressor.

3. Fridge Won’t Turn On

If your refrigerator is completely off and refuses to start, it could be an electrical issue or a bad compressor. The compressor needs to start up every time the fridge runs through its cooling cycle. If the compressor fails, the fridge will have difficulty running its cooling cycle properly, leading to a fridge that won’t turn on or cool at all.

Before jumping to conclusions, check the fridge’s power cord, fuse, and thermostat settings. But if everything else seems to be working and the fridge still won’t turn on, the compressor might be the issue.

4. Overheating or Excessive Heat Around the Fridge

A refrigerator should not feel hot to the touch, but if you notice the area around your compressor is overheating, that’s a strong indication of compressor failure. A properly functioning compressor should maintain a consistent temperature and never overheat. If it’s getting unusually hot, it could be that the compressor is either working overtime or has become defective.

This heat buildup can spread to the surrounding components of the fridge, such as the condenser coils and the motor. Excessive heat can also lead to other issues, like damage to the fridge’s wiring, which only worsens the problem.

5. Increased Energy Bills

A compressor that isn’t functioning correctly can cause your refrigerator to work harder than necessary. As a result, it may run continuously to try to reach the desired temperature, leading to higher energy consumption and a spike in your electricity bills. If your utility costs suddenly increase without any other obvious cause, the compressor might be malfunctioning, causing the fridge to work overtime.

This energy inefficiency is one of the telltale signs of a compressor problem, especially when other common signs of malfunction are present as well.

6. Frost Buildup in the Freezer

If you notice a layer of frost forming in your freezer, it could be an issue with the compressor. The compressor is responsible for circulating refrigerant throughout the fridge and freezer. When it’s not functioning properly, refrigerant can build up in the wrong areas, leading to frost accumulation in the freezer. This frost buildup can impact cooling efficiency and cause additional strain on the compressor.

7. Fridge Takes Longer to Cool Down

A faulty compressor may struggle to circulate the refrigerant properly, which means the fridge will take longer to cool down after the door has been opened. If you find that it takes much longer than usual for your fridge to cool off after loading groceries or after frequent door openings, that’s another clue the compressor may be the problem.

If the compressor is running inefficiently, it’s not only going to increase your fridge’s cooling time but can also prevent your refrigerator from reaching the right temperature.

Step-by-Step Guide to Testing a Refrigerator Compressor

If you’ve noticed one or more of the signs we discussed earlier, it might be time to test your refrigerator compressor to see if it’s the source of the problem. Don’t worry—it’s not as complicated as it may seem. With a bit of patience and a few tools, you can perform a basic diagnostic check yourself.

Tools You’ll Need:

Multimeter (a device to measure electrical current)
Screwdriver
Safety gloves
Flashlight (optional, but helpful for visibility)

Step 1: Unplug the Refrigerator

Safety is always the first priority. Before you start any testing, make sure to unplug your refrigerator. This will prevent any potential electrical shocks or other safety risks while you’re working on the compressor and its related components.

Step 2: Locate the Compressor

Next, you’ll need to find the compressor. In most refrigerators, the compressor is located at the back of the appliance, near the bottom. It’s usually a large, cylindrical part, and it may be covered by a metal casing. Depending on the model, you may need to remove a few screws to access it.

Take a moment to inspect the area around the compressor for any visible damage or wear, such as burned-out wires or signs of overheating.

Step 3: Test the Compressor’s Continuity

Now comes the technical part: testing the compressor’s continuity. Using your multimeter, set it to the resistance (ohms) setting. Then, connect the multimeter’s probes to the terminals of the compressor. You should be looking for continuity, which indicates that the compressor is in working condition.

If the multimeter reads a value of zero or very close to zero, that’s a sign of a short circuit. If the reading is “infinite,” it could mean the compressor is completely dead. Either way, the compressor isn’t functioning correctly and needs to be repaired or replaced.

Step 4: Check the Start Relay and Capacitor

If the compressor has continuity, the next step is to check the start relay and capacitor. These two components help the compressor start up and maintain smooth operation. A faulty relay or capacitor could be causing the compressor to fail.

Test the start relay with your multimeter by placing the probes on the relay’s terminals. If the multimeter shows an open circuit or no continuity, the relay is bad and needs replacing. Likewise, if the capacitor is damaged or no longer holding a charge, it will affect the compressor’s performance.

Step 5: Test the Compressor’s Overload Protector

Some refrigerators are equipped with an overload protector, which prevents the compressor from running too hot. If this protector malfunctions, the compressor may stop working. To test the overload protector, simply remove it from the compressor and check for continuity with your multimeter. No continuity means the overload protector is faulty.

Step 6: Reassemble and Test the Refrigerator

Once you’ve completed the necessary tests and made any repairs or replacements, it’s time to reassemble the refrigerator. Put all parts back in place, plug the fridge back in, and monitor its performance. If it’s cooling properly again, you’ve likely fixed the problem! If the issue persists, it could be time to call in a professional.

What to Do If Your Compressor Fails the Test

If your tests indicate that the compressor is indeed the problem, there are a few options depending on the severity of the issue. You could try to repair the compressor, replace individual components, or go for a full compressor replacement. Here’s a breakdown of what to do in each scenario.

1. Compressor Repair

In some cases, the compressor itself may still have some life left in it. If you’re comfortable with repairing it, you can attempt to fix it by replacing damaged parts, such as the start relay or overload protector. It’s important to note that compressor repair can be quite technical, and it may require special tools.

If you’ve diagnosed the compressor issue but are unsure of how to proceed, consulting a professional technician is always a safe option. A pro can help repair your compressor and save you the hassle of replacing the entire unit.

2. Replacing the Compressor

If the compressor is beyond repair, replacing it is the next logical step. Unfortunately, replacing the compressor is a complex task that typically requires a professional technician. The process involves removing the old compressor, installing a new one, and recharging the refrigerant. It’s best to leave this to the pros to ensure everything is done correctly.

While compressor replacement isn’t cheap, it’s often the most cost-effective option compared to buying a new refrigerator. So, if your fridge is in otherwise good condition, getting the compressor replaced may be worth it.

3. Consider a New Refrigerator

In some cases, if the compressor is completely shot and your fridge is old, it may be more cost-effective to purchase a new refrigerator altogether. This is especially true if the cost of replacing the compressor is too high or if the refrigerator has other issues besides the compressor.

If you’re facing the decision of whether to repair or replace your fridge, take into account the age of the appliance and the cost of repairs versus buying a new model. A new fridge will come with modern features, better energy efficiency, and a warranty to give you peace of mind.

I hope this guide helps you better understand how to test and diagnose a refrigerator compressor. While the process can be a bit tricky, it’s worth trying to troubleshoot the issue yourself before calling a repairman. If you do end up needing professional help, knowing exactly what’s wrong can save you time and money. Best of luck with your fridge repairs!

Frequently Asked Questions

Is it safe to test a refrigerator compressor myself?

Testing a refrigerator compressor involves working with electrical components, so it’s important to follow safety guidelines. If you’re not confident in your ability to perform the test, it’s better to hire a professional.

Can a bad compressor cause food to spoil?

Yes, if the compressor isn’t working properly, your refrigerator won’t maintain the correct temperature, which can lead to food spoilage.

Do I need a multimeter to test the compressor?

Yes, a multimeter is essential for checking the compressor’s continuity and diagnosing electrical issues like short circuits or open circuits.

Is a refrigerator compressor expensive to replace?

Yes, compressor replacement can be pricey, often costing hundreds of dollars. The price varies depending on the model and labor costs.

Can I fix a refrigerator compressor myself?

While you can perform basic tests on the compressor, repairing or replacing the compressor itself typically requires professional help due to the complexity of the job.

Is it better to repair or replace a broken refrigerator compressor?

If the compressor is severely damaged and the refrigerator is old, it might be better to replace the appliance rather than repair the compressor.

Do I need to replace the capacitor along with the compressor?

If the capacitor is faulty, it’s generally recommended to replace it along with the compressor to avoid further issues.

Can I clean the condenser coils to improve compressor performance?

Yes, cleaning the condenser coils helps improve the efficiency of your refrigerator’s compressor and cooling system. Make sure the coils are free of dust and debris.