The situation when the sounds of falling objects are heard while working refrigeration unit often confuses the owner. You open the door, check the shelves, but the inside is empty, but the strange knock clanging noise is repeated with alarming regularity. This is not mysticism or hallucinations, but completely understandable physical processes occurring inside a complex system.
Sometimes the sound source is actually inside the chamber, and sometimes vibration is transmitted from the compressor or elements defrost systems. It is important not to ignore these signals, as they can indicate either harmless expansion of materials or a serious malfunction of compressor or the fan. Let's figure out why the illusion of falling objects is created and what to do in each specific case.
Physics of ice: thermal expansion and defrosting
The most common cause of sounds reminiscent of falling glass balls or ice lumps, lies in the processes of freezing and thawing of moisture. In modern models with a system No Frost or drip defrosting, the formation of ice is a normal mode of operation, but its cyclic destruction creates an acoustic effect.
When the temperature in the freezer changes sharply, the ice crust on the evaporator cracks. Large pieces of ice may fall off the walls or heat exchanger and fall to the bottom of the chamber or onto the fan blades. It is this dull blow that is perceived by the user as the fall of a heavy object. This especially often happens when turning on or off the heat exchanger compressor.
In addition, the materials from which the internal plastic of the chamber is made are subject to thermal expansion. When temperature conditions change, the walls can emit clicks, which in the silence of the night sound like small parts falling. This is absolutely normal for refrigerators many brands and does not require specialist intervention.
⚠️ Attention: If the sound of falling ice is accompanied by a complete absence of cold or the formation of a huge “fur coat” on the back wall, it may be faulty Defrost heating element or timer In this case, the ice does not have time to melt and falls in pieces, blocking the operation of the system.
To minimize this effect, it is necessary to monitor the condition of seals doors. If the rubber is worn out, warm air enters the chamber, humidity rises, and ice forms more intensely, creating more noise when breaking off.
Fan and foreign objects in the chamber
In models with forced air circulation, the sound of the fall may hide work fan. If foil from food packaging or a light plastic bag gets into the freezer, the air flow can pick them up and throw them onto the walls or obscure the blades.
When foil gets into the work area fan a characteristic cracking sound occurs, which can be mistakenly interpreted as a fall many small items. The foil hits the plastic blades, creating a rhythmic knock. It is important to immediately remove the foreign object, as it can damage impeller or jam the motor.
It is also worth checking the fastening of the fan itself. Over time, the plastic guides may become loose and the entire assembly will begin to vibrate against the chamber wall. This creates the illusion that something heavy inside is rolling or falling with each switching cycle.
- 🧊 Ice chips: Small pieces of ice caught in the drainage hole can rattle there like coins in a piggy bank.
- 🥡 Packaging: Light bags from frozen vegetables often become a source of noise during operation blowing.
- ❄️ Ice on the blades: If the fan is frozen, the ice from it can break off and fall, creating an impact sound.
To diagnose this type of noise, it is recommended to completely defrost unit during the day. This will remove excess ice and accurately determine whether the sound has disappeared. If after defrosting the noise disappeared, but returned a week later, there is a problem in the defrost system defrost.
Compressor: when the unit itself “falls”
Sometimes the sound source is not inside the chambers, but in the lower part of the housing, where it is located compressor. When starting or stopping the engine, a sharp jump in refrigerant pressure may occur, which causes water hammer in the pipes. This sound is often described as the fall of a heavy metal object.
In addition, it is compressor attached to the frame on special shock-absorbing springs or rubber feet. If these fasteners are worn or loose, the motor housing may hit the metal frame or tubes during vibration. As a result, a loud clang is heard, which echoes throughout the entire body. condenser. The result is a loud clanging sound that echoes throughout the entire body.
Particular attention should be paid to the condition of the pipelines. Copper tubes through which circulation freonchange their linear dimensions when heated and cooled. If they are located too close to each other or to the cabinet walls, during thermal expansion they can touch and make a loud knocking sound falling down the body.
In some cases, the sound of falling comes from the valves inside compressor. This indicates that the node's resource is exhausted. If the unit is old, such a sound may be a harbinger of failure motor compressor.
Rattling of dishes and products on the shelves
Do not discount the banal vibration transmitted from the operating unit on items stored inside. Even if it seems to you that there is nothing in the refrigerator, small parts can create noise simulating a fall.
Glass shelves, if they do not sit tightly in the grooves or do not have rubber seals, can bounce from the microvibration of the case. This is especially noticeable in older models, where the plastic of the guides has already dried out. The sound of glass sliding is perceived very clearly.
The products themselves can also be a source of noise. Glass pickle jars, drink bottles, or plastic containers may become dislodged by vibration. If the bottom of the shelf is slippery, the object can slowly slide and eventually fall, creating that very scary sound.
| Object | Cause of noise | Elimination method |
|---|---|---|
| Glass shelf | Vibration of the case | Put silicone gaskets |
| Plastic boxes | Slipping of the runners | Lubricate the runners or level the drawer |
| Bottles/Cans | Displacement during vibration | Use organizers or clamps |
| Egg tray | Empty containers rattle | Close lid or remove tray |
Also check egg trays and door pockets. Empty plastic cells often rattle when you slam a door or work fan. This creates the illusion that something broke or fell inside.
☑️ Diagnosis of the sound source
Defrost system and drainage
In refrigerators with a system No Frost water generated during defrosting of the evaporator flows into a special pan located above compressor. If the drain tube is clogged or frozen, water can accumulate and then suddenly drain in large quantities.
The sound of water pouring or drops falling into the hot compressor pan can be very loud. Sometimes pieces of ice get stuck in the drainage system, which, when thawed, fall down the tube, creating a characteristic knocking sound similar to falling pebbles.
If the pan is not securely fastened, the stream of water can cause it to vibrate or even move. Water, falling on the hot body compressor, instantly boils, which is also accompanied by hissing and clicking noises, which can be confused with falling objects.
⚠️ Attention: If you hear gurgling and splashing water, check whether it is overfilled pallet The water must have time to evaporate. If there is always a puddle under the pen, it means that the system evaporation cannot cope or the tightness of the circuit is broken.
To clean the drainage, you can use a special flexible brush or warm water. It is important not to damage the inner walls of the tube so as not to disrupt the outflow of condensate in the future.
Deformation of the housing and external factors
Sometimes the reason lies not in mechanics at all, but in the physics of the materials of the housing itself. The plastic of the inner chamber and the metal of the outer casing have different coefficients of thermal expansion. When there is a sudden change in temperature (for example, after loading a large amount of warm food), the walls may “shoot.”
These sounds are often described as cracking or clicking, but in certain acoustic contexts they can sound like light objects falling. This is especially true for refrigerators thin walls or after transportation, when the unit has not yet fallen into place.
It is also worth checking what the refrigerator is on. If the floor is uneven or the legs are not adjusted, the cabinet may warp. During operation compressor vibration is transmitted to the floor, causing a resonance, which can create sounds of objects moving in adjacent cabinets or on the walls, which is mistakenly attributed to the refrigerator.
When it's time to call a technician
Despite the fact that many sounds are regular, there are situations that require professional diagnostics. If the sound of a fall is accompanied by a change in the nature of the operation unit (stopped freezing, works without stopping), this is an alarming signal.
A loud metallic clang upon startup, similar to a falling wrench, may indicate destruction of the internal elements. compressor. In this case, operating the device is dangerous and can lead to complete failure of the expensive unit.
If you have ruled out all household causes (ice, food, dishes), and the sound persists and intensifies, it is better to contact a specialist. The technician will be able to accurately determine whether the source of the sound is a sign of a malfunction circulation systems or refrigerant.
Frequently asked questions (FAQ)
Why do you hear something in a new refrigerator? falls?
In a new refrigerator, parts are often ground in and materials are adapted. The sounds may come from bubbles in the insulation (foam) popping, plastic expanding, or moisture remaining in the system freezing and spalling. Usually, after 1-2 weeks of operation, these sounds disappear.
Is it dangerous if the sound is made by ice?
The sound of falling ice itself is not dangerous. However, if too much ice forms and falls constantly, this may indicate a leak in the door or a malfunction of the defrost system, which will ultimately lead to a breakdown of the fan or overload of the compressor. silently. However, if there is a sudden change in pressure or the presence of gas bubbles in the liquid (which is for a working system), a flowing or gurgling sound may occur, which is sometimes confused with the falling of small objects. compressor.
Could the falling sound be made by freon?
The freon in the system is under pressure and circulates silently. However, if there is a sudden change in pressure or the presence of gas bubbles in the liquid (which is for a working system), a flowing or gurgling sound may occur, which is sometimes confused with the falling of small objects.
How to distinguish the sound of ice from a compressor failure?
The sound of ice is usually dull, occurs periodically (cyclically) and often after defrosting. The sound of a faulty compressor is most often a metallic clang, hum or knock, which is synchronized strictly with the moment the motor is turned on and sounds sharper and louder.