The situation when a refrigerator Bosch begins to make unusually loud sounds often takes the owner by surprise and causes anxiety. German technology is famous for its reliability and quiet operation, so any deviation from the norm is perceived as a signal of a serious breakdown. However, a strong hum does not always indicate a critical malfunction of the unit. Sometimes it’s a matter of incorrect installation or temporary operating mode.
Before calling a technician or panicking, you need to carefully listen to the nature of the sound. This can be a monotonous hum, periodic gurgling, a sharp knock or a high-frequency whistle. Correct identification of the noise source is the first and most important step to solving the problem. In some cases, it is enough to simply wait until the device completes the defrosting cycle, in others, you will need to adjust the legs or completely replace the compressor.
In this article we will analyze in detail the main reasons why the refrigerator Bosch may make noise, and provide an algorithm of actions for self-diagnosis. You will learn to distinguish normal operating sounds from signs of malfunction, and also learn what tools you will need to fix most common problems.
⚠️ Attention: Before starting any diagnostic or repair work, be sure to unplug the refrigerator from the electrical outlet. Working with live electrical appliances without appropriate qualifications is prohibited and dangerous to life.
Natural sounds of refrigeration equipment
Many users are faced with the purchase of modern equipment for the first time No Frost or LowFrost, and for them the characteristic sound of operation may seem too loud. It is important to understand that refrigerant circulation through the tube system is always accompanied by sounds. Liquid freon, turning into a gaseous state and back, makes sounds reminiscent of water pouring, a slight hissing or gurgling. These sounds can be heard especially clearly immediately after turning on the device or after opening the door.
In addition, in modern models with an automatic defrosting system, water drainage and ice melting mechanisms are periodically activated. At this moment, you can hear the characteristic cracking of plastic or the dull thud of drops of water falling into the drain pan. Thermal expansion The materials from which the inner box and evaporator are made also causes clicks, especially noticeable at night, when there is silence in the apartment.
If your The refrigerator Bosch emits a quiet, uniform hum, which either intensifies or subsides, this is most likely the normal operation of the compressor. Modern inverter motors can operate in different modes, and the sound of their rotation changes depending on the load. If the hum is not accompanied by vibration of the case and does not interfere with normal sleep at a distance of 1-2 meters, then no technical intervention is required. Carry out a simple test: place your palm on the side wall of the refrigerator. If you feel a slight, barely noticeable vibration and hear a smooth hum, this is normal operation of the compressor. If the vibration is strong and is transmitted to the floor, the problem must be looked for in the installation. no technical intervention required.
Problems with installation and vibration of the case
One of the most common reasons why the refrigerator Bosch loudly hums or trembles is a banal violation of the installation rules. German engineers design equipment with the expectation of a perfectly flat surface. If the floor is sloped or the feet of the appliance are not adjusted, resonance will occur. In this case, even a working compressor causes the entire housing to vibrate, creating a lot of noise.
To fix this problem, you will need a building level. Place it on the top panel of the refrigerator and check the horizontal position in two directions. Adjustment is made using the front legs, which can be twisted or unscrewed. Rear wheels usually serve only for transportation and do not bear the main weight, but make sure that they do not interfere with stability.
Another important point is the distance to walls and furniture. The refrigerator needs space for air to circulate around the condenser (black grille at the back). If the device is moved close to the wall, vibration can be transmitted to building structures, increasing the hum. Also check whether the internal shelves or products are touching the walls of the chamber, as this may cause rattling.
☑️ Diagnostics of refrigerator installation
Often owners forget to remove the transport bolts or clamps, if they were provided for in the design, although in modern models Bosch the compressor is usually mounted on springs inside the housing. Make sure nothing is loose inside the cameras. Remove each shelf and drawer one at a time and turn on the empty refrigerator. If the noise disappears, then the reason was in resonating objects inside.
⚠️ Attention: Do not install the refrigerator in close proximity to heating appliances or in direct sunlight. This forces the compressor to work at its limit, which increases the noise level and shortens the service life of the unit.
Faults of the compressor and start relay
The heart of any refrigerator is the compressor. If you hear a loud, increasing hum that ends abruptly with a click, followed by silence, and after a while the cycle repeats, this is a sign of problems with starting the engine. Most often it is to blame starting relay. This device is responsible for supplying a starting pulse to the motor windings. If the relay fails, it cannot start the compressor the first time, causing characteristic clicks and humming.
In more serious cases, the compressor itself may be faulty. Wear of bearings or internal piston groups leads to metallic clanging or strong vibration that is transmitted to the entire body. If the refrigerator Bosch hums so much that it can be heard throughout the entire apartment, and at the same time it freezes slightly, the motor is likely to fail or the system is leaking.
To diagnose the compressor, you can carefully (observe safety precautions!) touch its body during operation. It should be warm, but not hot. If the engine overheats and shuts down due to thermal protection, emitting a loud hum, professional repair is required. Replacing the compressor yourself requires special equipment for evacuation of the system and charging with freon.
Is it possible to replace the start relay yourself?
Yes, if you have electrical skills. The relay is located on the back wall of the refrigerator, on the compressor itself, in a black plastic or metal casing. You need to photograph the connection diagram, remove the old relay, buy a similar one (the markings must match) and install a new one. However, if the reason was not in the relay, but in the motor itself, replacing the relay will only help for a short time.
It is also worth paying attention to the compressor mounting. In models Bosch the motor is often suspended on springs inside the housing to dampen vibrations. If one of the springs jumps off or bursts, the compressor begins to bang against the walls of the housing or tube, creating a deafening knock and clang. In this case, it is necessary to remove the back cover, check the suspension and, if necessary, fix the motor again.
Fan noise in the No Frost system
Refrigerators Bosch with the system No Frost are equipped with one or more fans that circulate cold air. Over time, dust can become trapped in the fan bearings or they can dry out, causing an unpleasant whining or buzzing sound. Sometimes the noise intensifies when you open the door, since in many models the fan continues to work or, conversely, stops, changing the tone of the sound.
Another common cause of fan noise is ice freezing on its blades or in the immediate vicinity of them. This happens if the door seal is broken or the door is often opened in a hot room. The ice crust interferes with free rotation, and the fan begins to hum, trying to turn, or touches the ice with its blades.
To check the fan, you need to defrost the refrigerator. Unplug the appliance, open the doors and leave it for at least 12-24 hours. If after complete defrosting and drying the noise disappears, but returns after a few days, then the problem is in the water drainage system or seals. If the hum remains immediately after switching on, most likely you need bearing replacement or the fan itself.
| Type of noise | Probable cause | Solution method |
|---|---|---|
| Monotonous howl | Fan bearing wear | Lubricating or replacing the fan |
| Crack during rotation | Ice on the blades | Complete defrosting (24 hours) |
| Whistling | Clogged air ducts | Cleaning the ventilation system |
| Vibration of the housing | Imbalance blades | Replacing the air circulation unit |
Foreign objects and fasteners
Sometimes the cause of noise lies in small things that are easy to overlook. During operation, foreign objects may get into the gap between the refrigerator body and the rear wall where the condenser is located. This could be a piece of foil, a plastic bag, or even a toy if there are children in the house. When the compressor operates, vibration is transmitted to these objects, causing them to rattle or knock on metal tubes.
It is also worth checking the fastening elements. Loose rear panel mounting bolts, shelf supports, or interior lighting elements may resonate with the motor's operating frequency. Run your hand over all visible screws and plastic parts. If you find a loose part, simply tighten it or seal the gap with a piece of foam rubber or rubber.
Pay special attention to containers with food inside. Glass bottles or jars placed close to each other may cause a ringing sound when the shelf vibrates. Rearrange the products to prevent them from touching. Check that the lids on the containers are tightly closed, as loose lids may rattle due to fan operation.
⚠️ Attention: Never use sharp objects (knives, screwdrivers) to remove stuck objects in the condenser grille at the back. You can damage thin tubes with freon, which will lead to a refrigerant leak and expensive repairs.
When you need to call a specialist
Despite the possibility of self-diagnosis, there are situations when professional intervention is inevitable. If, after defrosting, checking the installation level and removing foreign objects, the refrigerator Bosch continues to make noise, and the quality of freezing food has deteriorated, this is a technical malfunction. The symptoms are especially alarming when the compressor runs continuously without turning off and gets very hot.
You also need the help of a technician if you hear the sound of gas escaping (hissing) or smell a specific chemical smell. This indicates depressurization of the system. In such cases, use of the device must be stopped immediately. An attempt to independently repair the refrigerant circulation system without special equipment and a license is not only ineffective, but also dangerous.
A specialist will conduct a full diagnostic using pressure gauges and testers. He will check the pressure in the system, the integrity of the motor windings and the electronic control module. Only professional repairs using original spare parts Bosch guarantees the restoration of factory characteristics of silence and energy efficiency.
Noise prevention and extension of service life service
In order for your refrigerator Bosch to serve for a long time and quietly, it is important to follow the operating rules. Defrost regularly, at least once every six months, even if you have a system No Frost. This will allow you to remove hidden ice in hard-to-reach places and give the compressor a rest. Wipe the door seals and lubricate them with special silicone grease to maintain elasticity and tightness.
Keep the rear condenser clean. Dust accumulating on the black grille impairs heat transfer, causing the motor to work harder and noisier. Vacuum the back of your refrigerator every 3-4 months. Also check that the ventilation holes inside the chamber are not clogged with food, which interferes with air circulation.
Timely maintenance is the key to silence. If you notice that the refrigerator begins to hum a little louder than usual, do not expect a complete breakdown. Early diagnosis often allows for simple adjustments or cleaning, avoiding the need to replace expensive components. Taking good care of equipment Bosch pays off with years of silent and reliable operation.
How often should you wash the inside of the refrigerator?
It is recommended to carry out general cleaning inside the refrigerator every 1-2 months. Use mild detergents without abrasives. Cleanliness inside prevents the appearance of unpleasant odors and reduces the load on the air filtration system (if there is one).
Frequently asked questions (FAQ)
Why does the new Bosch refrigerator hum loudly in the first days?
The new refrigerator may be louder due to the fact that all the parts have not yet gotten used to each other to a friend. In addition, when loading for the first time, the compressor works in enhanced mode to cool the entire volume of the chambers and products. Usually, after 3-5 days of operation, the noise level decreases to nominal.
Is it normal for the refrigerator to gurgle after defrosting?
Yes, this is absolutely normal. After defrosting, water remains in the drainage system and evaporator tubes, which, when the compressor operates, begins to circulate along with the refrigerant, causing gurgling and pouring sounds. After a few hours, when the system returns to operating mode, the sounds will become quieter.
Can the magnetic tape on the door make noise?
The magnetic tape itself cannot make noise, but if the seal is deformed or suctioned too tightly, a loud bang may occur when the door is opened. If the seal does not fit tightly, air can pass through the gap, creating a whistle. Check the tightness of the door around the entire perimeter.
What to do if the refrigerator makes a sound similar to a creaking?
A squeak most often indicates friction of plastic parts or dried grease in moving mechanisms (for example, in the air supply damper or door hinges). Try lubricating the hinges and check if anything is touching the inside of the camera. If the creaking comes from the compressor, this may be a sign of wear.