Does the refrigerator knock during operation: normal or broken?

We analyzed reports from technicians and reviews from owners to create a checklist of the most likely causes of knocking - from trivial to critical. And at the end of the article you will find a FAQ with answers to frequently asked questions, including unique cases of knocking in refrigerators with linear compressors (for example, Beko ProSmart Inverter)which are often confused with a breakdown.

1. Normal operating sounds: when knocking is not dangerous

Not every knock in the refrigerator is a sign of a malfunction. Modern models are equipped with many mechanical and electronic components that produce characteristic sounds during operation. Here's what can be considered normal: inverter models (for example, the norm:

• 🔄 Switching compressor modes: inverter models (for example, Hitachi R-WB400smoothly regulate power, which may be accompanied by a slight knocking sound. In non-inverter refrigerators (Atlant MXM-1808), the compressor turns on/off with a loud click.
• ❄️ No Frost system operation: the fan and defrost heater make periodic sounds similar to for crackling or quiet knocking. Especially noticeable in models Bosch KAN92VI30 or Indesit DF 5200.
• 💧 Refrigerant circulation: when the compressor starts, freon begins to move through the tubes, which can cause gurgling or knocking sounds (more often in refrigerators with a top freezer, for example Samsung RT-22 HAR4DSA1).
• 🔧 Thermal expansion of parts: plastic panels, door seals and even metal tubes “play” when the temperature changes, making clicks. This is especially noticeable in new refrigerators during the first 1-2 weeks of operation.

How to distinguish normal knocking from breakdown? Pay attention to regularity And volume sound. If the refrigerator knocks rhythmic (for example, every 10-15 minutes) and the sound does not increase over time, this is most likely a feature of the model. But if the knocking has become louder, more often or appears. data-i="86">(for example, after a move or a power outage), it is worth checking the equipment. suddenly (for example, after moving or a power outage), it is worth checking the equipment.

2. Mechanical causes of knocking: what to check first

If the knocking appears suddenly or becomes more intense, start by checking mechanical elements. In 60% of cases, the problem is solved without calling a technician. data-i="101">mechanical elements

2.1. Uneven installation of the refrigerator

Even a slight misalignment of the housing can cause vibration and knocking when the compressor operates. This is especially true for models with lower location of the motor (for example, Liebherr CN 4313 or Gorenje NRK 6191).How to check:

• 📏 Use a building level to measure the tilt of the refrigerator on all four sides. Allowable skew is no more 1–2. mm.
• 🔧 Adjust the front legs (they usually have threads). The rear legs in most models are adjusted by turning a special bolt or shimming.
• 🧲 Check that the back wall of the refrigerator does not touch the furniture or the wall. The minimum gap should be 5–7. cm.

2.2. Touching the compressor or fan tubes

If the refrigerator is knocking rhythmicallyas if something hits the body, there are two possible reasons:

1. Refrigerant pipes touching the back wall or other parts. This often happens after transportation or careless cleaning. In models Samsung RL-44 or Indesit BIAA 13 the tubes may move away from the fasteners and vibrate.
2. Fan blades (in systems No Frost) touch ice or frost. This is accompanied not only by knocking, but also deterioration of cooling.

To fix the problem:

1. Disconnect the refrigerator and carefully move it away from the wall.
2. Visually inspect the compressor tubes (they should be secured with clips. If the tube comes off, return it to its place without applying any pressure). effort.
3. In models with No Frost check the fan: if there is ice on the blades, defrost the refrigerator for 12–24 hours.

2.3. Dishes or food inside the refrigerator

Sometimes the source of knocking becomes glass shelves, jars or plastic containers, which vibrate from the operation of the compressor. This is especially noticeable in refrigerators with metal bars (For example, Beko GNE 114620). Check:

• 🥛 Do the cans or bottles touch each other or the walls?
• 🍳 Are the glass shelves wobbly (sometimes the fastenings become loose over time).
• 🧊 In the freezer: does ice form, which can break off and fall (typical for models without No Frost, for example, Birusa 101).

3. Breakdowns that cause knocking: when repairs are needed

If mechanical causes are excluded, but the refrigerator continues to knock, the problem may lie in internal malfunctions. nodes. Below is a table of the most likely breakdowns and their symptoms.

The most dangerous failure in this list - depressurization of tubes. If the refrigerator knocks metal and at the same time does not freeze, immediately unplug it! Further work will lead to overheating compressor and its failure.

4. Features of knocking in refrigerators of different brands

Some brands have design featureswhich is why their refrigerators knock more often than others. Let's look at the most common cases.

4.1. Refrigerators with linear compressors Models with technology (for example, 204) are known for their quiet operation, but sometimes users complain when switching modes. This is normal: a linear compressor regulates power smoothly, but when changing speed, light tapping may occur LG with linear compressors

Models with technology Linear Inverter Compressor (For example, LG GA-B459 YDQZ) are known for their quiet operation, but sometimes users complain about light tapping when switching modes. This is normal: a linear compressor regulates power smoothly, but when changing speed, problems may occur. microvibrations.

However, if the knocking becomes loud or irregular, check:

• 🔌 Network voltage: linear compressors are sensitive to surges. At a voltage below 200V they may operate unstably.
• 🧲 Compressor mounting: in some batches of refrigerators LG 2020–2022 there were cases of weakening shock absorbers.

4.2. Refrigerators Samsung with a system Twin Cooling Plus

In models with two compressors (for example, Samsung RB-37 J5240), knocking can come from:

• 🔄 Synchronization of motor operation: if one compressor turns on before the other, short-term vibration occurs.
• ❄️ Flow switching valve refrigerant (characteristic click when changing cooling mode).

If knocking is accompanied error on the display (for example, 5E or 8E), this may indicate a malfunction of the control board.

4.3. Refrigerators Atlant i Biryusa (domestic models)

In refrigerators of these brands, knocking is often associated with:

• 🧊 Formation of ice in the freezer (due to a leaky door or wear of the seal).
• 🔧 Features of compressor mounting: in some models, shock absorbers wear out faster due to a rigid suspension.

5. Knocking diagnostics: step-by-step instructions

To accurately determine the cause of the knocking, follow this algorithm:

1. Disconnect the refrigerator from the network and listen: if the knocking continues, the problem is in mechanical parts (for example, a fan or tubes). If the knocking stops, the fault is compressor or electronics.
2. Check the installation: tilt the refrigerator back 45° and see if the compressor swings. If so, you need to adjust the legs or replace the shock absorbers.
3. Inspect the back wall:
   • 🔍 Check the integrity of the refrigerant pipes (there should be no dents or abrasions).
   • 💨 Make sure that the fan (if any) rotates freely (gently twist the blades by hand).
4. Start the refrigerator in test mode:
   • Set the maximum cooling mode (Super Freeze or Fast Cool).
   • Put your hand on compressor: if it vibrates strongly or hot the problem is there.

If after diagnosis the cause of the knocking remains unclear, use built-in self-diagnosis system (if it is in your model). For example, in refrigerators Bosch series KAN to do this you need to press and hold the button Super 5 seconds.

6. technicians: criteria for urgent repair

Not all breakdowns can be repaired yourself. Contact the service center if:

• ⚡ The knock is accompanied by sparking or burning smell (risk of short circuit).
• ❄️ Refrigerator does not cool, but the compressor works without stopping.
• 💦 A puddle of oil appeared under the refrigerator (possible damage handsets). (a sign of depressurization of the system).
• 🔊 The knocking began louder after moving or falling (tubes may be damaged).
• 📛 The display shows error (for example, E1, F5 or dH v models Samsung).

The cost of diagnostics in service centers starts from 500 ₽, but some workshops offer a free check for subsequent repairs. Before the technician’s visit:

• 📝 Write down refrigerator model (located on a sticker inside the camera or on the back).
• 🎥 Take a video the nature of the knocking - this will help the technician quickly identify the problem.
• 📋 Prepare warranty card (if the refrigerator is under warranty, repairs may be free).

7. Prevention: how to prevent knocking in the refrigerator

To minimize the risk of extraneous sounds, follow these recommendations:

• 📍 Installation:
  • The refrigerator should be placed on a flat, hard surface (not on carpet or linoleum).
  • Use anti-slip pads under the legs (sold in hardware stores).
• 🔌 Power supply:
  • Connect the refrigerator via voltage stabilizer (especially important for houses with old wiring).
  • Avoid use extension cords - they can cause power surges.
• ❄️ Operation:
  • Do not overload the door - this leads to distortion and vibration.
  • Defrost the refrigerator at the first sign of ice (even if there is one) data-i="329">Maintenance No Frost).
• 🛠 Service:
  • Once a year, clean the back wall of dust (use a vacuum cleaner or soft brush).
  • Check the door seal - if it is worn out, the refrigerator works harder, which increases vibration.

For refrigerators with the No Frost system, it is especially important to monitor clean the drainage hole. A clogged drain can cause water to accumulate and make a knocking sound when it freezes. Clean the hole with special brush or a straw at least once every 6 months.

FAQ: Frequently asked questions about knocking in the refrigerator