A sudden noise that appears, reminiscent of the work of a construction tool, can unbalance any owner of household appliances. If your the refrigerator began to make strange sounds like a drill, this is a sure sign that a critical malfunction has occurred in the refrigerant circulation system or in the compressor drive. This problem cannot be ignored, since intense vibration and overheating can lead to complete failure of the unit in a matter of days.
The first thing you need to do when you hear this frightening noise is to listen carefully to the nature of the sound and determine its location. A metallic grinding sound, a high-frequency squeak, or a low-frequency hum with vibration indicate completely different points of failure. In this article, we will analyze in detail the mechanics of the occurrence of such sounds and help you understand whether you can fix the problem yourself or you will need to call a technician.
Often, equipment owners are faced with a situation where the device is working normally, but when the engine starts, a sharp, increasing hum is heard. This may be due to the fact that compressor it is trying to start, but it does not have enough starting torque, or the rubbing parts have already exhausted their service life. It is important not to panic, but to consistently check all possible causes, ranging from simple settings to complex diagnostics of internal components.
Anatomy of noise: why the compressor hums
The main source of sound in any refrigerator is compressorwhich is essentially sealed pump. Inside this assembly, a piston compresses freon gas, creating pressure in the system. If you hear a sound similar to a drill, this often indicates that the internal mechanisms of the compressor are experiencing enormous resistance or friction. Piston group The valves may be worn out, and the valves may be deformed, which creates a characteristic metallic clanging and hum.
Another common reason for this behavior is the engine trying to overcome a jam. When The refrigerator makes a drill sound, this may mean that the motor rotor is clamped in the stator due to lack of lubrication or mechanical damage to the windings. At this moment, the current consumption increases sharply, and the hum becomes shrill. If you do not turn off the device at this moment, the windings may burn out, which will lead to expensive repairs.
It is also worth considering that modern inverter models can make specific sounds when operating at high speeds. However, the sound of a drill is not the norm even for them. Unlike ordinary humming, the sound of a construction tool always indicates mechanical failure or a critical imbalance in the system.
⚠️ Attention: If the humming is accompanied by a burning smell or visible sparking in the area of the start relay, immediately unplug the cord from the outlet. Further operation may lead to a fire.
Problems with the starting relay and electrical system
Often the reason that the refrigerator hums like a drillbut does not start or starts with difficulty is a malfunction of the starting relay. This small element is responsible for supplying a starting pulse to the motor winding. If the relay contacts are stuck or the winding is burned out, the engine begins to hum, trying to turn over, but cannot gain the required speed.
Diagnostics of the relay does not require complex equipment. You will need to remove the back cover of the unit, locate the black or gray plastic block attached to the side of the compressor, and carefully remove it. Inside you will see a copper coil and a moving core. If the relay makes a rattle sound when shaken, it means that the internal spring or core is damaged, and the element requires replacement.
It is also worth checking the integrity of the windings of the compressor itself using a multimeter. The resistance between the contacts must be within certain limits (usually from 10 to 30 Ohms for different pairs of contacts). If the multimeter shows one (open) or zero (short circuit), then electric motor it is faulty. In some cases, the problem lies in the oxidation of the contacts on the connector, which creates a high contact resistance and a characteristic crackling sound.
☑️ Diagnostics of the starting relay
Mechanical wear of bushings and suspensions
The compressor inside its metal casing is suspended on special springs to dampen vibrations. Over time, these springs can stretch, burst, or become dislodged. As a result, during operation the motor begins to vibrate, touching the inner walls of the casing. This metallic clanging and rattling sound is often described by users as the sound when the refrigerator works like a drill.
Another critical component is the bushings in which the compressor shaft rotates. With prolonged use or operation in conditions of low oil (due to freon leakage or leakage), the bushings wear out. Backlash appears, the shaft begins to beat, creating increasing noise. If worn parts are not replaced in time, the shaft may completely jam, and the compressor will have to be thrown away.
Diagnostics of the suspension is only possible when disassembling the compressor, which is not recommended to do at home due to the difficulty of sealing. However, if you hear that the sound changes when you tilt the refrigerator body, this is a sure sign of broken motor suspension geometry. In such cases, sometimes reinstalling the springs helps, but more often the entire unit needs to be replaced.
Is it possible to repair the suspension yourself?
Theoretically, it is possible if you have the skills to work with tools and access to spare parts. However, this requires opening the sealed compressor casing, which violates the factory sealing. After the repair, professional sealing of the casing and evacuation of the system will be required, so it is more economically feasible to replace the entire compressor.
The influence of the refrigerant on the operation of the system
The amount of freon in the system directly affects the load experienced by the compressor. If a leak develops in the system and there is too little refrigerant, the engine starts to run “idle” or, conversely, tries to compensate for the lack of pressure with more intense work. This can lead to overheating and a change in the nature of the sound.
The situation is especially dangerous when there is little freon left in the system, but the compressor continues to pump. The oil that circulates along with the gas stops returning normally to the engine crankcase. It begins oil starvation, the rubbing parts heat up and begin to make a grinding noise. The sound may be similar to the operation of a dry mechanism, which is often confused with the noise of a drill.
It is also worth mentioning water hammer. If liquid freon enters the compressor instead of gaseous (which happens when the thermostat malfunctions or is incorrectly charged), the piston experiences a shock load. This causes a sharp knocking and humming noise. In modern models with inverter control electronics may try to compensate for this by changing the rotation speed, which creates strange sound effects.
| Symptom | Possible cause | Probability repair |
|---|---|---|
| Hum at startup, then silence | Faulty start relay | High (replacement relay) |
| Constant hum like a drill | Wear bearings/bushings | Average (compressor replacement) |
| Humming + lack of cold | Freon leak / compressor wedge | Complicated repair |
| Metal clanging inside | Torn engine mount | Average (replacing springs/compressor) |
Vibration of the housing and foreign objects
Before sinning with complex mechanics, it is worth excluding trivial causes. Sometimes the refrigerator makes sounds due to the fact that it stands unevenly. Check the legs of the unit: if one of them does not touch the floor or, on the contrary, is too twisted, the body warps and the compressor begins to resonate with the floor, creating an increased hum.
Also pay attention to the space around the refrigerator. The sound of a drill may not come from the device itself, but from a vibrating shelf next to it, or from objects that have fallen behind the refrigerator. Vibration from a running motor is transmitted to nearby objects, causing them to rattle. Often it is enough to simply move the equipment 5-10 cm away from the wall for the noise to disappear.
Check the integrity of the plastic elements inside the cameras. A cracked shelf or loose drawer may vibrate from the compressor. Make sure that bottles and cans do not touch each other or the walls of the refrigerator. Sometimes even a small piece of ice that gets on the fan (in No Frost systems) can create a sound very similar to the operation of a power tool.
No Frost system and ventilation
In refrigerators with a No Frost system, fans are responsible for air circulation. If the fan blades become contaminated with ice or have a foreign object (such as a piece of packaging) wrapped around them, the fan motor will begin to hum. At high rotation speeds, this sound can be very similar to the operation of a drill or turbine.
Ice forms on the blades when the defrost system malfunctions. The heating element does not turn on, the evaporator becomes overgrown with a “fur coat”, and the fan begins to touch ice build-ups. This creates a rhythmic crackling and humming sound. To test this version, you need to defrost the refrigerator for 24 hours. If after defrosting the sound disappears, but returns after a few days, the problem is in the defrosting system (heating element, timer or sensor).
The bearings of the fan itself may also fail. In this case, they begin to hum and creak. Replacing the fan is a simple procedure and usually does not require calling a technician if you have basic skills with a screwdriver and the ability to disassemble the plastic panels inside the freezer.
⚠️ Attention: When disassembling the No Frost system, be extremely careful with the plastic parts. In the cold, plastic becomes brittle and breaks easily if handled carelessly. Allow the chamber to warm up a little before removing the panels.
When you need to call a technician
There are a number of situations when self-repair is not only impractical, but also dangerous. If you determine that the sound is produced by itself compressor (metal grinding inside the hermetic unit), then it is impossible to open it yourself without special equipment (oxygen-acetylene torch, vacuum pump, pressure gauge station).
Also, a technician is needed if the problem is related to freon leak. Finding the leak requires professional equipment. Attempts to simply “add gas” without eliminating the hole will lead to repeated failure in a short time. In addition, different models of refrigerators require different types of refrigerant, and an error in selection can finish off the compressor.
If the refrigerator is under warranty, any independent repair will lead to loss of warranty. In this case, the only correct solution is to contact an authorized service center. Even if the problem seems simple (for example, replacing a relay), it is better to call a specialist in order to maintain the right to free repairs in the future.
Is it worth replacing the compressor on an old refrigerator?
If the refrigerator is more than 10-12 years old, replacing the compressor is often not economically feasible. The cost of a new motor, replacement work, refilling with freon and calling a technician can be up to 70-80% of the price of a new similar refrigerator.
Prevention and proper care
To extend the life of the compressor and avoid the appearance of extraneous sounds, it is important to follow the operating rules. Do not place the refrigerator close to a wall; allow air to circulate freely around the rear grille. Overheating is the main enemy of the motor, leading to accelerated wear and tear.
Regularly defrost the refrigerator, even if it is a No Frost system (preventative defrosting once a year is useful). Keep the condenser (grids at the back) clean: dust and animal hair accumulated between the lamellas impair heat transfer, causing the compressor to work longer and more intensely.
Do not overload the refrigerator with food and do not put hot food in it. A sharp jump in temperature forces the system to work at its limit, which can cause water hammer or engine overload. Following these simple rules will help you avoid a situation when the refrigerator hums like a drill at the most inopportune moment.
Is it possible to continue to use the refrigerator if it hums like a drill?
Short-term operation is possible, but undesirable. If the sound appears suddenly and is constant, it is better to turn off the device. Long-term operation in this mode will lead to overheating of the windings or failure of the compressor. If the relay is buzzing, the refrigerator may simply not turn on until it cools down.
How much does it cost to replace a compressor?
The cost consists of the price of the unit itself (from 5 to 15 thousand rubles, depending on the model) and the cost of the work of a specialist (from 3 to 8 thousand rubles). The total amount often exceeds 10 thousand rubles, so before repairing it is worth assessing the residual value of the refrigerator itself.
Why can a new refrigerator hum?
New models, especially with inverter compressors, can make sounds that seem strange, but are the norm. However, the sound of a drill is uncharacteristic for the new device. This may be a manufacturing defect or the result of improper transportation (for example, if it was transported lying down and was not allowed to settle before turning it on).
How to transport the refrigerator correctly so as not to damage the compressor?
It is recommended to transport the refrigerator strictly in an upright position. If this is not possible, the angle of inclination should not exceed 40 degrees. After transportation in a horizontal position, the unit must stand for at least 4-8 hours (preferably a day) before turning it on, so that the oil flows back into the compressor crankcase.