The situation when the refrigerator is cracking at the backoften takes owners by surprise, causing concern for the safety of products and the performance of expensive equipment. The sounds can range from a quiet, intermittent crackling sound to a loud crackling sound that sounds like gunshots or blows. Understanding the nature of these sounds is the first step to solving the problem, since cracking does not always indicate a breakdown.
In most cases, the operation of the refrigeration unit is accompanied by a certain level of noise, however non-standard sounds they require attention. It is important to distinguish between normal system operation due to expansion of materials or refrigerant circulation and signals of mechanical failure. In this article, we will analyze in detail the main reasons why the back of the refrigerator makes a cracking sound, and determine in which cases you can handle it yourself.
Please note that ignoring extraneous sounds in the early stages can lead to more serious consequences and expensive repairs. Diagnostics should be carried out when the device is turned off and on to accurately localize the sound source. Let's look at the main factors that influence the acoustic background of your refrigerator.
Natural causes of crackling noise when the refrigerator is operating
Before sounding the alarm and looking for a service center number, it is worth considering the physical processes that are the norm for any refrigeration equipment. Users are often frightened by sounds that actually indicate the normal operation of the unit. Thermal expansion materials are one of the most common reasons.
The internal walls of the chamber, the evaporator and other plastic or metal elements are subject to constant temperature changes. When cooled they contract, when heated (when the compressor stops) they expand. This process is accompanied by a characteristic crackling or clicking sound, reminiscent of the cooling of the plastic of a new TV.
Another natural source of sound is movement refrigerant through the system tubes. Freon circulates under pressure, and its passage through the capillary tube or the entrance to the evaporator may be accompanied by gurgling, hissing or slight crackling. This is especially noticeable in models with a system No Frost, where the refrigerant actively moves along the circuit.
⚠️ Attention: If the crackling sound is heard only when the compressor is turned on or off and is not accompanied by a loss of cold, most likely this is a natural process of expansion of materials.
It is also worth considering the operation of the system No Frost. In such models, the defrost heating element is periodically turned on, which heats the evaporator. Sudden heating of frozen condensate or ice crust can cause ice to crack. This is absolutely normal and does not require intervention.
How to distinguish a normal crack from a breakdown?
Normal cracking is usually quiet, periodic and does not increase over time. Sounds of breakdown are often accompanied by vibration of the body, humming, or a change in the operating mode of the refrigerator (stopped freezing, works without stopping).
Thus, if your refrigerator makes quiet clicks or crackles, but the food is frozen efficiently, and the temperature regime is not disturbed, there is no reason to panic. This is simply the “voice” of physics with which modern technology lives.
Incorrect installation and problems with ventilation
Often the cause of extraneous sounds is a banal violation of installation rules. If The refrigerator is not level., vibrations from a running compressor are transmitted to the housing and amplified, causing rattling and crackling. The back wall may resonate with the floor or adjacent walls.
It is important to ensure the correct clearance between the back wall of the refrigerator and the wall of the room. The minimum distance should be at least 5-10 cm. If the refrigerator is moved close, air circulation is disrupted, the condenser overheats, which can cause additional noise and crackling from the expansion of overheated parts.
☑️ Checking the installation of the refrigerator
Another factor is touching objects. Vibration can be transmitted to water pipes if they are located nearby, or to furniture standing close to each other. In this case, it is not the unit itself that may be cracking, but the objects around it.
To fix the problem, you need to:
- 🛠️ Adjust the front support legs so that the refrigerator is stable and does not wobble.
- 📏 Move the equipment away from the wall to the distance recommended by the manufacturer.
- 🔍 Inspect the space behind for the presence of foreign objects that may vibrate.
After correct installation, the noise level should decrease and extraneous sounds should disappear. If the cracking noise remains, the problem lies deeper, inside the technical part.
Malfunctions of the compressor and start relay
If natural causes and installation problems are excluded, you should pay attention to the “heart” of the refrigerator - compressor. It is this that creates the main pressure in the system. A loud cracking, knocking or clanging noise coming from the rear below often indicates problems with the motor or its mounting.
One of the common reasons is failure start relay. This device is responsible for starting the engine. If the relay is faulty, it may make a loud clicking or cracking sound when you try to start the compressor. In such cases, the motor may hum, but not start, or start with a characteristic metallic sound.
The internal parts of the compressor may also wear out. The bearings or piston group wear out over time, which leads to metallic knocking and crackling sounds. If the compressor makes a loud metallic clanging sound and vibrates strongly, this is a critical sign of its imminent failure.
| Symptom | Possible reason | Required actions |
|---|---|---|
| Loud click and silence | Malfunction of the starting relay | Replacing the relay |
| Metallic knocking during operation | Wear of compressor parts | Replacement of the compressor |
| Vibration and rattling | Loose fastenings | Tightening bolts, replacing shock absorbers |
Diagnostics of the compressor requires caution. If you hear that the motor is trying to start, clicks, but does not start, it is better to immediately disconnect the device from the network. Long-term operation in this mode can lead to burnout of the motor windings.
Problems with the defrosting system and fan
In refrigerators with a system No Frost a fan located in the freezer (often behind the back wall) is responsible for circulating cold air. If there is a failure in the defrosting system, an excessive amount of ice builds up on the evaporator.
When the ice becomes too much, the fan blades begin to touch the ice crust. This causes a characteristic crackling, noise and hum. The sound may increase when the freezer door is opened, since in some models the fan works more actively at this moment.
The reasons for the formation of ice can be different:
- ❄️ Malfunction of the defrost heating element (does not heat).
- 🌡️ Breakage of the defrost sensor (does not give a signal to turn on the heating).
- 💧 The drainage hole is clogged (the water does not drain and freezes).
If you hear a cracking noise, similar to blades hitting a hard object, most likely the fan is hitting ice. In this case, the refrigerator must be completely defrosted (for 10-12 hours with the power turned off). If the sound disappears after defrosting, but returns a week later, the problem is in the elements of the defrosting system.
⚠️ Attention: Do not try to break off the ice with a knife or sharp objects! You can damage the evaporator or touch the fan blades, which will lead to expensive repairs.
It is also worth checking the fastening of the fan itself. If it is loose, the motor may vibrate and make a cracking noise against the chamber walls. In some cases, simply tightening the mounting screws or lubricating the bushings helps.
Refrigerant circulation and hydraulic blow
Sounds associated with the movement of freon are usually described as gurgling or hissing. However, in some cases, the circulation of the refrigerant may be accompanied by sharper sounds, reminiscent of crackling or short knocks. This phenomenon is often called water hammer in miniature.
When the compressor suddenly increases pressure, the liquid phase of the refrigerant can quickly move through the tubes. If there are small kinks or design features in the system, the flow can hit the walls of the tubes, causing vibration and sound. This often occurs immediately after turning on the compressor.
If the crackling noise is heard precisely in the area of the condenser grille