What can it be, when the refrigerator is making knocking noise



Any refrigerator, even the most modern one, makes noise. Sometime louder, sometime quieter, it all depends on its condition. When you first turn on the appliance, the sound may be slightly louder than usual, but as soon as the refrigerator reaches the desired temperature, the noise level will decrease. It is not normal to hear a loud knock coming from the refrigerator compartment. This is a sign that there are problems with some details.

An atypical knock emitted by the device may be associated with:

  • ice buildup around the evaporator fan;
  • movement of tubes that bring water to the refrigerator;
  • blocking of the ice generator;
  • expansion of plastic parts of the refrigerator;
  • Loose compressor mountings or physical deterioration;
  • overloaded shelves and utensils standing close to the inner rear wall of the refrigerator;
  • hitting pieces of furniture that are too close to the appliance;
  • unstable position of the refrigerator on the floor;
  • ingress of a foreign object into the cooling system.

refrigerator is making knocking noise

Some of the above reasons are very quickly eliminated on their own. Try to solve the knocking problem by starting with the obvious: rearrange the products, adjust the height of the legs, free up at least 5-10 cm of space around the refrigerator. Do not be afraid of any knock, in most cases it does not pose a danger to the functionality of the device. But the problem should not be completely ignored.

The most common causes of knocking related specifically to the operation of individual parts or systems are described below.

Ice formation around the evaporator fan

When there is a knock in the refrigerator, and you have ruled out all the most obvious causes, then your next step should be to check the condition of the evaporator fan. This part is part of the cooling system. It draws warm air in, lowers its temperature to the desired value, and then a small fan evenly distributes it throughout the refrigerator compartment.

During fan rotation, a knock is generated if the plastic blades are covered with a thick layer of ice. Also, unpleasant noise can occur due to the impact of the fan on the accumulation of ice that has formed nearby.

Evaporator fan covered with frost

Rapid and continuous knocking during the entire cycle of the evaporator fan is a clear sign of freezing of the part.

How to solve a problem? It is necessary to remove all ice from the blades and the protective structure. Do not do this with a knife or other improvised tool. Turn off the refrigerator, remove all food from it and leave for 24 hours for the ice to melt on its own at room temperature.

Noise from water pipes

After checking the evaporator fan, listen for the noise coming from the water pipes connected to the refrigerator. All modern models equipped with dispensers and ice makers must be connected to a water supply system. Communications are usually located behind the refrigerator: between it and the wall.

How can knocking from water pipes occur? This happens when they hit the wall or back of the refrigerator, and a water hammer effect occurs in the pipes. The pressure in the system changes dramatically, because of which the hose or pipe seems to “jump” and at the same time can reach the surfaces surrounding them.

Noise from water pipes

To solve the problem, you must first make sure that there are no leaks anywhere. Next, see if the pipes and hoses are securely attached to the wall or back of the refrigerator. When they are fixed with clamps or other fasteners on a flat surface, they have no room to maneuver in the air.

Based on the above, your main task to eliminate knocking is to securely fix the elements of the plumbing system. When they are not moving, they cannot make a knock.

Ice maker lock

If your refrigerator is capable of making ice cubes, then you should definitely check out the system that does the job. In most cases, the ice maker forms ice cubes, and then they are stored in special containers placed inside the refrigerator. In other models, you just need to press the ice supply handle, and the frozen cubes will automatically slide out of the dispenser located outside the refrigerator door.

If you hear a knocking sound in this part of the refrigerator, it is likely that it is caused by an ice cube stuck in the dispenser. It blocks the exit from the icemaker, and the moving parts of the latter continue to work. They are the ones who make the noise.

Ice maker lock

What are your steps to solve the problem? Remove the stuck cube. But it is important to do this very carefully. Do not attempt to operate with your fingers, you can easily injure yourself on the moving parts of the dispenser. Turn off the refrigerator first. Then there are two ways: you can try to get the stuck cube using a long thin tube, or you can leave the device turned off so that the ice itself melts.

Plastic parts of the refrigerator

A loud knock may be emitted by the plastic from which some parts of the refrigerator are made. This is due to the elementary laws of physics. In the refrigerator several times a day, automatic defrosting is activated, which is necessary in order to melt the frost and ice accumulated in the system.

During this time, the plastic heats up a little, and then, when the cooling is turned on again, there is a sharp temperature drop, and there is a rather loud popping noise that resembles a knock. In this case, you cannot fix the problem, because the process is natural and does not indicate any problem. Every year, the knocking volume may increase slightly, which indicates the wear of parts.

Plastic parts of the refrigerator

Compressor problems

This part of the refrigerator is the center of the cooling system, its main active element. The compressor compresses the refrigerant and circulates it throughout the sealed system. The average life of a part is about 10 years, maybe a little more, depending on the manufacturer.

If you have checked all possible causes of knocking, but the problem is not solved, only compressor diagnostics remains. Perhaps it broke completely or some part of it failed. Unfortunately, you cannot repair the compressor yourself.

The Environmental Protection Agency (EPA) claims that only a person who has trained in a special course and is certified can fix problems in a sealed system. And replacing the compressor is just working with a sealed system.

Compressor make noise

If you suspect something is wrong with the compressor, you will have to call the service and arrange for the services of a certified master. He will most likely confirm the need for a complete replacement of the part. If your refrigerator at the time of the breakdown has served for many years (about 10), then it makes sense to think about buying a new model: more modern and energy efficient.

Frequently Asked Questions

How can I defrost the refrigerator in the shortest possible time?
Modern models are equipped with a function such as defrosting. When it starts, the heating element turns on, which quickly melts all the frost and ice inside. Each appliance has a different way to enable this feature, so you should read the user manual for your refrigerator model.

Is it possible to defrost the freezer without turning it off?
There are several ways to defrost your freezer without turning it off. The first, and safest, way is to run a forced defrost cycle on the refrigerator. The function is laid down and tested by the developers, so it is safe for the device. The second way is to put a pot of boiling water in the freezer. The hot steam will speed up the thawing of the ice inside, especially around the evaporator fan that makes a thud.

Is it possible to speed up the process of defrosting ice on the evaporator fan with a hair dryer?
No, it’s dangerous. Manufacturers do not recommend using a hair dryer or heat gun for accelerated defrosting. These appliances create a directional flow of very hot air that can melt and deform plastic fan blades.

What can I do to keep my ice maker quiet?
To get rid of the knock coming from the ice maker, it is necessary to remove the pieces of ice stuck in its moving parts. If you still can’t clean the ice maker, turn it off and it will stop making noise.

Can you fix a refrigerator compressor?
In some cases, the master will be able to do this. But if it has come to the point that the compressor is knocking, then with almost 100% probability we can say that the part has worn out and needs to be replaced. Therefore, you should not spend money on repairs that will be useless, but it is better to immediately install a new compressor.