The situation when when you close the refrigerator door, something bubblesis familiar to many owners of household appliances. This sound can be a subtle rustling sound or a loud gurgling sound, reminiscent of water pouring in pipes. For most users, this becomes a cause for serious concern, since it intuitively seems that something abnormal is happening inside the unit.
However, you should not rush to conclusions about a breakdown. The operation of the refrigeration circuit involves complex physical processes associated with changes in the aggregate states of the refrigerant. Often it is the moment of the door slamming that provokes a short-term change in pressure, which causes an acoustic response in the system.
In this article we will analyze in detail the physics of the process, the differences between normal operation and a malfunction, and also consider scenarios when seething really signals the need to call a technician. Understanding these nuances will help you save time and money without giving in to panic due to the natural sounds of equipment.
Physics of the process: why the sound appears precisely when closing
To understand the nature of the sound, you need to consider what is happening inside fridge compartment at the moment of sealing. When you open the door, warm air saturated with moisture comes inside. The sharp closing of the flap creates a piston effect: the volume of air inside is sharply compressed, creating a pressure difference.
At this moment, the refrigerant circulating through evaporatorresponds to a change in heat transfer. If the compressor is active at this moment or has just stopped, the liquid in the tubes may begin to move more actively or, conversely, stagnate, creating characteristic sounds.
It is important to note that modern models of refrigerators, especially those with No Frostsystem, have a complex air duct system. The flow of air passing through them when the door is abruptly closed can also produce whistling or gurgling sounds, which are mistaken for the operation of the compressor.
Is the refrigerant working normally or is it a sign of a malfunction?
The main question that worries users: is freon bubbling the norm? In the vast majority of cases, yes. The refrigerant in the system constantly changes its state from liquid to gaseous and back. This process is never completely silent.
⚠️ Attention: If bubbling is accompanied by a complete lack of cold in the chambers or icing of food, this is no longer the norm, but a symptom of a serious leak or compressor breakdown.
The sound is considered normal. which:
- 🔊 Occurs periodically, and does not work continuously for hours.
- 🔊 Is not accompanied by body vibration or strong buzzing.
- 🔊 Goes away on its own within a few seconds after closing the door.
- 🔊 Does not affect the temperature inside cameras.
However, if noise becomes a constant companion to the operation of the unit and intensifies over time, it is worth paying attention to the condition of the system. Sometimes the sound of a working fan or the knocking of valves is mistaken for bubbling, which also requires differential diagnosis.
The influence of the No Frost system on acoustics
Refrigerators with the system No Frost (or Low Frost) are more complex than their predecessors with a drip defrosting system. The presence of forced air circulation fans adds its own nuances to the sound picture of the device.
When the door is closed, the air flow sharply changes direction or speed. If there are small obstructions or ice in the air ducts, turbulence that can be heard as gurgling or whistling may occur. In addition, such models often use a more fluid refrigerant, which makes sounds easier when moving through thin capillary tubes.
The peculiarity of the system No Frost is that the evaporator is hidden behind a plastic panel. The sound coming from there can resonate with the voids of the case, intensifying. Therefore, what is heard as loud seething can actually be a quiet flow of gas in a remote node.
Owners of such models should know:
- ❄️ The sounds often intensify when the defrost system is started or stopped.
- ❄️ Closing the door can provoke brief start of the fan.
- ❄️ Temperature changes in the air ducts cause expansion and contraction of the plastic, which also gives a sound background.
Why is it louder in No Frost?
In refrigerators with the No Frost system, the evaporator is located in a separate compartment (usually in the freezer or behind the back wall). The sound of freon circulation is transmitted through metal tubes to the entire body, creating a resonance effect. In older models with a “crying wall,” the evaporator is often built right into the back wall of the chamber, and a layer of ice or plastic muffles sounds.
Diagnostics: table of symptoms and causes
To independently determine the condition of your refrigerator, we suggest using the diagnostic table. Compare the nature of the sound with other observed symptoms.
| Character of the sound | Concomitant symptoms | Probable cause | Status |
|---|---|---|---|
| Silent transfusion | There is cold, standard operating mode | Refrigerant circulation (normal) | Normal |
| Loud gurgling + humming | The refrigerator does not freeze, the motor hot | Clogged capillary tube | Repair |
| Whistling when closing | Door closes tightly | Vacuum air / seal | Normal/Adjustment |
| Gurgling + ice on the walls | Food freezes, water on the floor | Faulty defrost system | Repair |
If you observe the symptoms indicated in the second and fourth lines, a technical malfunction is likely. In the case of clogging freon cannot circulate normally, creating plugs that make loud sounds when the compressor tries to push gas.
⚠️ Attention: An independent attempt to clean the capillary system without a vacuum pump and pressure gauges will lead to complete loss of refrigerant and compressor failure.
When bubbling indicates a blockage or leak
If when you close the refrigerator door, something bubbles it is too intense and this is accompanied by a deterioration in the quality of freezing, we may be talking about a partial blockage of the system. Most often, the capillary tube or filter drier becomes clogged.
In this state, the refrigerant passes through a narrow section at high speed, creating a characteristic whistling-gurgling sound. At the same time, the compressor works almost without interruption, trying to reach the set temperature, but due to circulation disturbances, efficiency drops.
Signs indicating a problem with the circuit:
- 🛑 The compressor works continuously without turning off.
- 🛑 Condenser grille at the back the refrigerator is only partially cold or warm.
- 🛑 In the freezer, food begins to thaw.
- 🛑 The sound changes from a quiet rustling to a loud “plop”.
A freon leak may also be accompanied by strange sounds if there is air or moisture left in the system. However, more often a leak leads to complete silence, since there is simply nothing for the gas to circulate. Therefore, loud seething more often indicates a mechanical obstacle to the flow of gas, and not a lack of it.
Problems with the seal and pressure difference
Sometimes the source of the sound lies not inside the refrigeration circuit, but in the door itself. If sealing rubber lost elasticity or becomes dirty, the tightness of the closure is broken.
When the door slams, the air inside is compressed. If the seal does not fit tightly, air can come out noisily or, conversely, be sucked in through microscopic gaps, creating a sound similar to gurgling or whistling.
To check the condition of the seal:
- Carefully inspect the rubber around the entire perimeter for cracks.
- Do a test with a sheet of paper: hold the sheet with a door and try to pull it out. It should come out with difficulty.
- Check whether anything is preventing the tight closing (shelves, products).
It is also worth checking drainage hole. If it is clogged, condensation does not leave, but accumulates and can gurgle when vibration or air movement occurs. Cleaning the hole with a special soft wire or a brush often solves the problem of extraneous sounds associated with water.
☑️ Checking the door seal
Frequently asked questions and answers (FAQ)
Why does the refrigerator seethe only at night?
At night, extraneous noises in the apartment subside, and the operation of the refrigerator becomes more noticeable. In addition, at night the voltage in the network often drops, which can change the nature of the compressor’s operation, making it more “noisy” or causing a hum, which is masked by household noise during the day.
Is loud gurgling dangerous immediately after defrosting?
After defrosting, moisture may remain in the system. Until it completely evaporates or goes through the drainage, gurgling sounds may appear. If the sound does not go away after 4-6 hours of operation, it is worth checking the drain hole.
Can a new refrigerator boil?
Yes, new models are often louder than older ones due to the use of more efficient but fluid refrigerants (for example, R600a). The “break-in” period can last up to two weeks. If the cold is produced normally, there is no need to worry.
What to do if the seething turns into knocking?
Knocking is a more alarming symptom, indicating a mechanical malfunction of the compressor (broken valves, worn bearings) or beating of tubes against the housing. In this case, it is better to stop operation and call a technician for diagnostics.