Why Is My Refrigerator Making A Knocking Noise?

When summers are just around the corner, nothing freaks you out more than unexpected refrigerator problems. Especially when your refrigerator begins to make a knocking noise. In which case, this is the high time that you should seek out the root of the cause otherwise it could end up costing you a fortune.

However, fear not as we have all the bases covered, from the initial warning signs to the possible fixes.

The most likely reason for your refrigerator to make a knocking noise is down to the compressor or condenser fan.
This is commonly a case of the fan becoming blocked from a build up of dust, reducing air flow, resulting in a knocking or clicking noise.

Probable Causes:

Before delving into how you can begin to fix this issue, let us have a quick look through some of the most common causes:

Condenser fan motor or blade:

Next time your refrigerator makes a knocking noise, try to listen as to where the noise is coming from. For instance, if it comes from behind or at the bottom of the refrigerator, chances are that the condenser fan motor or blade are to blame. To reach the condenser fan motor, you may have to remove the panel, which takes less than a few seconds.

After this, you can check if the blades of the fan need cleaning, if not you’re probably going to need to check the motor.

If it is the motor causing this knocking noise, this is the first indication of a faulty motor. Luckily, such motors are replaceable so you won’t need to purchase a whole new refrigerator.

Evaporator fan motor or blade:

Evaporation is one of the significant processes of refrigeration. If it is malfunctioning, you’ll hear a knocking sound when the fridge door opens. This needs the same procedure as mentioned above, ensure that the blades are dirt-free or go for a new motor.

The Compressor:

Let us clarify further that the noise coming from the behind of the refrigerator is an indication of a plethora of causes. This can be a condensing mechanism or an unbalanced compression system. With this one, it is important to seek professional help.

Refrigerant circulation:

With all these probable causes, we can’t overlook the most obvious reason. This being the result of the refrigerant, which is pretty normal. You don’t have to go for any expert help, as with the transformation from gas to liquid proceeds, Freon passes through the compressors and condensers. That is how the knocking sound occurs which does sound alarming at first.

If it isn’t excessively loud and your refrigerator shows no decline in the cooling levels, then we suggest you simply ignore this knocking sound.

Water Hammers:

Water Hammers may sound daunting but they are easy to understand. Water Hammers occur when water flowing through pipes is forced to stop or change direction. Such as when a tap is turned off or a valve from an appliance shuts. This produces a loud knocking or “hammering” sound and if left unattended can cause damage.

Consider Reading: Why is my refrigerator making a humming noise?

How to diagnose a knocking noise on a Refrigerator compressor:

Let us share with you a few tips to help you diagnose the problem for yourself.

Step 1:

First of all, you have to figure out the place knocking noise is coming from. If your refrigerator makes knocking noise from the outside or behind the panel, it is most probably the leveling issue.

Step 2:

Get a helping hand and tilt the refrigerator backward, in this way it becomes easier for you to access the front legs. See if they are uneven, if so balance them out.

Step 3:

Thirdly, place the fridge back to it’s normal position. If the knocking persists, check whether the compressor it loose and get a screwdriver to tighten the bolts.

Normal Sounds and Noises made by your refrigerator:

Not every sound is worth worrying about, here is a list of common noises you’ll hear from your refrigerator that shouldn’t concern you.

Chirping sound:

This one is the most conventional sounds to hear while opening or closing the damper door. The damper door helps in preventing the sudden jolts while you shut the fridge door. The extra coating may cause a chirping sound which is typical and needs no special attention.

Clicking sound:

A clicking sound is produced when the defrost timer switches on or off.

Gurgling sound:

A gurgling sound takes place because of the water in the drainpipe, it can occur after several instances especially after closing the door. Freon converts from the gas state into liquid and the evaporation may leave behind some water. This water accumulates in the drain pipe and produces a gurgling sound.

Knocking sound:

The primary reasons include the consistency in the refrigerant circulation cycle. It may suggest the onset of many other problems like malfunctioning compressor or the condensing mechanism, as discussed above.

Consider Reading: Signs your refrigerator needs more Freon

Frequently Asked Questions:

Q1. Why does my refrigerator make a clunking noise?

Clunking noises occur when the compressor is loose or needs some professional maintenance.

Q2. Why does my refrigerator sound like a jackhammer?

This specific problem suggests that the water valve has stopped working or there’s some leakage in the drain pipes.

Q3. How do I stop my fridge from clicking?

The clicking sound can be stopped by replacing the compressor. Most of the time, it suggests a worn-out compressor or condensing pipes.


Let us end this debate on a concise note; the knocking noise isn’t always concerning and would be good advise to leave it a while to check if it persists. In the majority of cased, this noise comes from the compressor region or the condensing system. Above all, balancing the front legs of the refrigerator can also be an easy fix.

After all the suggested tips, if the knocking continues, consider contacting an expert.