A sudden hum in the refrigerator can turn a calm kitchen into a source of constant irritation. Extraneous noise often becomes the first signal that changes have occurred in the operation of the unit that require attention. Sometimes this is a harmless sound of flowing liquid, and in other cases it is a harbinger of a serious breakdown. compressor.
Many owners of household appliances panic when they hear an increasing hum, and immediately look for the service center number. However, calling a technician prematurely may not be necessary. In most cases, the problem is solved by simply adjusting the position of the housing or defrosting the chambers. Understanding the nature of sounds will help you save time and money.
In this article we will analyze in detail all the possible reasons why The refrigerator is humming, from design features to critical malfunctions. You will learn to distinguish between normal operating sounds and alarm signals, and also learn what steps you can take on your own to eliminate the hum.
Normal operating sounds of the refrigerator
Before sounding the alarm, you need to understand that a working refrigerator is not a completely silent device. Modern models operating on refrigerants like R600a or R134amake specific sounds during the circulation of freon. Quiet gurgling or liquid overflows inside the walls - this is a normal phenomenon, indicating the movement of refrigerant through the pipe system.
It is also worth considering the operation of the system No Frost. In such units, fans are periodically turned on to circulate air, which creates a monotonous low-frequency hum. After defrosting the evaporator, the sound may change, becoming louder or quieter. If the hum is uniform and does not interfere with sleeping in the next room, most likely the equipment is functioning normally.
What noise level is considered normal?
Modern refrigerators have a noise level from 30 to 42 dB. Sounds above 45 dB can already cause discomfort in quiet conditions, but short-term increases in volume when starting the compressor are acceptable.
It is important to distinguish the nature of the sound. The following is considered normal:
- 🔊 Uniform hum of the motor when the compressor is running.
- 💧 Quiet gurgling or hissing in the tubes.
- 🌀 Periodic fan noise (for models with the No Frost system).
Installation problems and vibration of the case
One of the most common reasons why The refrigerator is hummingis incorrect installation. If the unit is not level, resonance occurs, increasing engine vibration. The housing begins to rattle, and the compressor itself experiences increased load, which shortens its service life. The vibration is transmitted to the floor and walls, creating the effect of an increased hum throughout the entire apartment.
To diagnose this problem, just gently shake the refrigerator. If it is wobbly or one of the legs is not touching the floor, it needs adjustment. Most models are equipped with screw supports that can be turned by hand or with a wrench. Leveling is a prerequisite for stable operation.
⚠️ Attention: Never leave the refrigerator tilted for a long time. This can lead to distortion of the internal parts of the compressor and its failure.
Check the distance to walls and furniture. If the refrigerator is located close to the cabinets, vibration is transmitted to them, and they begin to hum like resonators. The gap should be at least 5-10 cm on all sides.
☑️ Vibration diagnostics
Malfunctions of the compressor and start relay
When the refrigerator hums louder than usual, and the sound comes directly from the motor, the problem may lie in compressor. This is the heart of the unit, and any changes in its sound require close attention. Bearing wear, shaft imbalance or problems with the windings can cause a strong hum that turns into a howl.
Often the culprit is starting relay. If it is faulty, the compressor may hum but not start, or may make a clicking noise before starting. In some cases, the relay simply cannot start the engine, and it idles, consuming current and making noise. Replacing the relay is a simple procedure, but requires turning off the power.
Symptoms of problems with the engine compartment:
- 🔥 Strong heating of the rear wall in the area of the motor.
- 🔌 Frequent shutdowns and attempts to start with clicks.
- 📉 Drop in performance (food stops freezing).
Vibration and noise of the fan (No Frost)
In refrigerators with a system No Frost the fan is responsible for air circulation. Over time, dust can get into the fan bearings or ice can freeze, which leads to imbalance of the impeller. As a result, a characteristic humming or howling sound appears, which can intensify when the door is opened (in some models the fan stops, in others it changes mode).
Sometimes the fan blades touch ice or icicles formed due to a broken seal or frequent opening of the door. Ice builds up on the evaporator and begins to interfere with rotation. In this case, complete defrosting of the refrigerator is required within 10-12 hours.
To check the fan, you need to:
- Disconnect the refrigerator from the mains.
- Remove the back panel in the freezer.
- Manually turn the fan blades - the movement should be free and silent.
⚠️ Attention: Before any manipulations inside the cameras, be sure to disconnect the device from the power supply. A humid environment and electricity are a dangerous combination.
Comparative table of causes of noise
For quick diagnosis, use the table below. It will help systematize observations and determine the probable source of the problem.
| Sound type | Probable cause | Difficulty of repair |
|---|---|---|
| Monotonous hum, rattling | Incorrect installation, touching walls | Minimum (adjustment) |
| Strong hum, motor heating | Faulty compressor or relay | High (replacement parts) |
| Howling sound, whistling | Fan No Frost (ice or wear) | Medium (defrost or replacement) |
| Gurgling, overflow | Freon circulation (Normal) | Not required |
When you need to call a technician
There are situations when self-repair not only will not help, but will also aggravate the situation. If after defrosting and leveling the legs the refrigerator continues to hum with increasing force, serious damage is likely. The appearance of a burning smell or smoke should also alert you.
A sealed circuit with freon cannot be opened independently without special equipment and skills. An attempt to replace the compressor with your own hands without evacuation of the system will lead to instant failure of the new motor. In such cases, professional diagnostics are required.
Call the service urgently if:
- 🚫 The compressor hums for 1-2 seconds and clicks, then silence (the cycle repeats).
- 🌡️ The refrigerator has stopped freezing, although the motor works.
- 💨 Smoke is coming from the back or you can feel scorched insulation.
Remember that timely contact with a specialist can save the products and the unit itself from costly restoration. Do not ignore changes in the sound background of your equipment, because they are the main language in which the refrigerator reports its status.
Is it possible to lubricate a humming compressor?
No, modern compressors are sealed units. They are filled with lubricant at the factory, and it is impossible to add oil or lubricate the bearings from the outside. Attempts to drill holes will lead to freon leakage.
FAQ: Frequently asked questions
Why did the new refrigerator start to hum a week after purchase?
New equipment often goes through a “breaking in” period. Compressor parts may make noise until they are designed. Also check whether the shipping bolts have been removed (if they were provided for the compressor) and whether the unit is level.
Can an empty refrigerator hum?
Yes, an empty refrigerator can hum more strongly due to the lack of products that act as sound-absorbing mass and cold accumulators. Filling the chambers helps stabilize the temperature and reduce the frequency of motor starts.
Does the temperature in the room affect the noise of the refrigerator?
Absolutely. In a hot room, the compressor is forced to work longer and harder to maintain the set temperature. This leads to overheating and increased hum. Try not to place the refrigerator next to the stove or radiators.
What to do if the refrigerator hums only at night?
At night, the general background silence is lower, so operating sounds become more noticeable. If the hum has not changed in character, but has simply become audible, this is normal. If the sound becomes sharp or intermittent, carry out diagnostics according to the instructions above.