The appearance of extraneous sounds in the operation of household appliances always causes concern for the owner, and a crackling sound in the refrigerator is no exception. This specific noise can range from a barely audible clicking sound to a loud, frightening crunching noise that disrupts restful sleep. Understanding the nature of sound is the first and most important step to maintaining unit performance and preventing food spoilage. In some situations, a characteristic crackling sound is an absolutely normal physical process that does not require the intervention of a specialist.
However, it is absolutely impossible to ignore the problem if it is regular and growing in nature. Extraneous noise often serves as the first signal that the internal components of the cooling system are overloaded or have failed. Mechanical friction, tube vibration, or electrical problems can quickly lead to costly repairs. Let's take a closer look at when you can sleep peacefully, and when you urgently need to look for the number of a service center.
Natural physical processes and expansion of materials
The most common and safest reason why a refrigerator makes a crackling sound lies in the laws of thermodynamics. The internal walls of the chamber, shelves and system elements No Frost are made of plastic and metal, which have different coefficients of thermal expansion. When there is a sudden change in temperature, for example immediately after the compressor is turned off or when loading a large amount of warm food, materials contract or expand. This process is accompanied by a characteristic sound reminiscent of the crackling of plastic or the bursting of bubbles.
Such sounds are especially common in new refrigerators that have not yet gone through the period of initial “grinding in” of materials. Over time, the plastic adapts to constant temperature changes and the amount of sound artifacts may decrease. It is important to note that in models with an automatic defrosting system, periodic crackling noises may be associated with the operation of of the defrost timer or switching modes, which is a normal situation for modern units.
If the crackling noise is heard exclusively at the moments of starting or stopping the engine, and also when short-term in nature, most likely, your equipment is working properly. Thermoregulator and temperature sensors send signals to the actuators, causing micro-movements of the plastic. This does not require repairs, but only getting used to the operating features of a particular model. However, if the sound becomes continuous or is accompanied by vibration of the case, you should proceed to a deeper diagnosis.
Mechanical reasons: fan and ice
In refrigerators with a system No Frost one of the main sources of noise is the fan, which provides circulation of cold air. If you hear a cracking noise, similar to the sound of branches snapping or blades hitting a hard object, the cause may be that the evaporator is frozen. When the defrost system does not work correctly, a layer of ice builds up on the fan blades or the walls of the evaporator chamber. When rotating fan impeller it touches this ice, producing a loud crack.
The second mechanical reason is wear of the bearings of the fan itself. Over time, the lubricant dries out, and the bushing begins to run dry, making grinding or cracking sounds. In this case, the fan requires replacement or, in rare cases, lubrication, if the design allows this to be done without compromising the seal. Ignoring this problem will lead to the fan motor burning out and the cold will stop flowing into the chamber.
How to check the fan without disassembling?
For initial diagnostics, you can carefully remove the back panel in the freezer (after defrosting the refrigerator). Manually turn the fan blades - they should rotate easily and silently. If you feel sticking or hear a crunching sound, the part is faulty.
It is also worth checking whether foreign objects have entered the fan operating area. A piece of polyethylene from the packaging or a label may be pulled in by the air flow and begin to crack against the grille. A visual inspection of the evaporator chamber will often help identify such little things. Removing the foreign body completely eliminates the noise.
Problems with the compressor and start relay
The heart of the refrigerator - the compressor - can also be a source of alarming sounds. If a cracking sound is heard when the engine starts, followed by a humming sound and then dying down (or clicking again and stopping), the problem lies in starting relay. This element is responsible for starting the engine, and if it malfunctions, the contacts can burn or stick, producing a characteristic electrical crackling sound. Long-term operation with a faulty relay will lead to combustion of the compressor windings.
Processes that cause noise can also occur inside the compressor itself. The weakening of the internal engine mount (the springs on which it is attached) leads to the fact that during operation it begins to hit the walls of the casing. This creates a metallic clanging and crackling sound. In addition, hydraulic shock of the refrigerant in the tubes, caused by an excess of freon or oil entering the system, may sound like bubbling or crackling.
If you notice that the compressor is running cyclically: it turns on, a crackling sound is heard, and it immediately turns off, this is a clear sign of overload protection. In such a situation, operating the refrigerator is impossible, as the food will begin to defrost. The start relay or, in the worst case, the compressor itself needs to be replaced. Independent repair of this unit without special equipment and skills is impossible and dangerous.
Improper installation and vibration of tubes
Often the reason for a banal crackling sound lies in the incorrect installation of the refrigerator. If the unit is not level, vibration from the operating compressor is transmitted to the housing and amplified by resonance. The tubes located on the rear wall may touch each other or the housing. When they vibrate, they begin to hit the metal, producing a rattling noise that can easily be mistaken for the crackling of internal mechanisms.
To eliminate this problem, you need to check the horizontalness of the installation using a building level. Height adjustment is made by twisting or unscrewing the front support legs. Vibration of tubes is eliminated by carefully bending them apart from each other with your hands (being careful not to damage the thin metal) or installing rubber pads at the points of contact.
☑️ Diagnostics of refrigerator installation
It is also worth paying attention to what is on the top panel of the refrigerator. Heavy objects that are placed unsteadily may resonate with chassis vibration. Remove all excess from the roof of the unit and check if the sound has disappeared. Sometimes the source of noise is the furniture itself, to which the refrigerator is moved, transmitting vibration.
Comparative table of causes and solutions
For ease of diagnosis, we have systematized the main causes of cracking noise into a single table. This will help you quickly navigate the nature of sound and decide on further actions. Remember that an accurate diagnosis can only be made by a specialist using measuring instruments.
| Sound type | Probable cause | Danger | Necessary actions |
|---|---|---|---|
| Rare clicks of plastic | Thermal expansion of materials | No | Observation, no repair needed |
| Crackling noise when starting the engine | Malfunction of the starting relay | High | Replacing the relay |
| Constant crackling in the chamber | Ice freezing on the fan | Medium | Defrosting, checking the defrost system |
| Metal clanging | Compressor falling off the cushions | High | Repair of the compressor compartment |
| Case rattling | Incorrect installation | No | Adjusting the legs, moving the tubes |
When a crackling noise indicates an electrical fault
The most dangerous type of crackling is an electrical crackling sound that resembles sparking. If you hear these sounds, accompanied by a burning smell or visible sparking in the electrical contact area, you must act immediately. The problem may lie in poor contact of the plug with the socket, damage to the wiring inside the housing or breakdown of the insulation of the motor windings. Electric arc can melt plastic elements and cause a fire.
⚠️ Attention: If a burning smell, smoke or obvious sparking, immediately unplug the refrigerator! Continued operation is strictly prohibited to avoid fire.
Often an electrical crackling occurs at the junction of the power wire with the terminal block. The weakened contact begins to heat up and melt, producing a characteristic crackling sound. In this case, it is necessary to replace the plug, socket or repair the wiring inside the unit. If you do not have the skills to work with electricity, entrust this work to a professional electrician or refrigerator repairman.
Prevention and operating rules
To minimize the risks of extraneous noise and extend the life of your refrigerator, it is important to follow simple operating rules. Regular defrosting (even for systems No Frost preventive defrosting is recommended once a year) helps to avoid the accumulation of excess ice on the evaporator and fan. Do not load hot food into the chamber - this creates an extreme load on the compressor and causes strong thermal expansion of the plastic.
Keep the condenser (grid at the back of the refrigerator) clean. A heat exchanger clogged with dust and animal hair causes the compressor to work longer and harder, which increases vibration and wear of parts. Periodically cleaning the back wall with a vacuum cleaner is an excellent habit for any equipment owner.
It is also worth considering that technical specifications and maintenance requirements may vary depending on the model and year of manufacture.
FAQ: Frequently asked questions
Why does a new refrigerator crack in the first days of operation?
This is a normal process of adapting materials. Plastic and metal undergo a cycle of compression and expansion during the first cooling cycles. Usually, after 3-5 days of operation, the sounds become quieter or disappear completely.
Can you continue to use the refrigerator if it is cracking?
If the cracking is caused by thermal expansion or vibration of the tubes, you can. If the sound comes from the compressor (electrical crackling, loud knocking when starting), it is better to stop operation until the reasons are determined in order to prevent final breakdown.
How much does it cost to repair if the starting relay burns out?
Replacing the starting relay is one of the most inexpensive types of repairs. The cost consists of the price of the part itself (which is small) and the work of the on-site technician. The exact amount can be found out only after diagnosing a specific model.
Does the level of filling of the refrigerator with food affect the crackling sound?
Indirectly - yes. An empty refrigerator changes temperature more quickly when the door is opened, causing the compressor to cycle more frequently and therefore generate more frequent thermal expansion sounds. A full load stabilizes the temperature.