The situation when one of the chambers in the refrigerator stops working always takes you by surprise. You open the door, expecting the usual cold, but inside it becomes noticeably warmer than it should be. At the same time, the adjacent compartment can continue to properly freeze food, creating the illusion of normal operation of the entire unit. This is a common problem faced by owners of both budget and premium models of equipment.
Modern two-chamber refrigerators are more complex than their predecessors, and the failure of one cooling circuit does not always mean a complete stop of the compressor. Often the engine continues to hum, trying to compensate for the loss of cold, but physically cannot reach the desired temperature in the problem area. Ignoring the first symptoms can lead to damage to a large number of products and higher costs for subsequent repairs.
In this article we will examine in detail the main reasons why freezer compartment or the refrigeration compartment ceases to perform its functions. We'll look at mechanical failures, electronics problems, and operating conditions that affect refrigerant circulation. Understanding these processes will help you make the right decision: call a technician immediately or try to fix the problem yourself.
Principles of operation of double-circuit and single-circuit systems
To understand why one part of the refrigerator works and the other does not, you need to understand its internal structure. There are two main types of cooling systems: single-circuit and double-circuit. In single-circuit models the cold is generated in the evaporator of the freezer, and then a fan or natural convection distributes it into the refrigerator compartment. If a failure occurs in such a system, most often it is the upper part that suffers.
Double-circuit systems (or models with the No Frost system) have independent evaporators for each chamber. This allows you to set different temperature conditions and defrost compartments separately. However, the presence of additional elements, such as a second solenoid valve or separate fan, increases the number of components that can fail. It is the complexity of the design that often becomes the cause of localized malfunctions.
It is important to note that in systems with one compressor and two evaporators, a special valve is used that switches the freon flow. If this mechanism jams in one position, one of the chambers is left without cooling. In older models without fans, the problem may lie in the freezing of the channels through which cold air flows from top to bottom.
⚠️ Attention: An attempt to independently open the cooling circuit without special equipment and skills will lead to complete failure of the refrigerator and require expensive refilling.
Diagnostics begins with understanding what kind of system is installed in your unit. This information is usually contained in the technical data sheet or on a sticker inside the camera. Knowing the type of system will help narrow the range of possible causes of failure and correctly formulate the task for a specialist.
Main symptoms of a malfunction and initial diagnosis
Before sounding the alarm, it is necessary to conduct a visual inspection and evaluate the nature of the refrigerator’s operation. The first and most obvious sign is a change in the temperature of the food. If milk turns sour in the refrigerator within a few hours, and the ice melts in the freezer, this is a clear signal of a problem. However, sometimes the symptoms are less obvious and require careful monitoring.
Pay attention to the operation of the compressor. If it works without interruption, hums louder than usual, or, conversely, turns on very rarely, this indicates a violation of heat exchange. In normal mode operation cycle the engine consists of periods of activity and rest. Constant operation indicates that the system cannot reach the desired temperature in one of the zones.
It is also worth listening to extraneous sounds. Gurgling, hissing, or whistling sounds may indicate a refrigerant leak or problems with freon circulation. In some cases, on the back wall of the refrigerator or inside the chambers, you can notice swelling, corrosion, or, conversely, a complete absence of frost where it should be.
Perform a simple defrost test. If, after completely turning off the unit for 24 hours and then turning it back on, the problem disappears for a short time and then returns, most likely the problem is a clogged capillary tube or a malfunction of the defrost system. This is an important diagnostic sign that is often overlooked.
Refrigerant leak: symptoms and consequences
One of the most common reasons why one chamber does not work is a banal freon leak. The refrigerant circulates in a closed circuit, and if a microcrack appears in the system, the gas gradually evaporates. Unlike oil in a car, freon is not consumed during operation, so its shortage always indicates a leak.
If there is a partial leak, the compressor continues to work, trying to pump the remaining amount of gas. As a result, the pressure in the system drops, and the refrigerant simply does not reach distant parts of the circuit. In refrigerators where the evaporator is located in the freezer, if there is a leak, it is the refrigeration compartment that first stops cooling.
It is difficult to visually determine a leak, since freon is colorless and odorless. However, indirect signs can be:
- 🔴 Black spots or swelling on the inner wall of the refrigerator (corrosion of the foamed evaporator).
- 🔴 Absence of the characteristic noise of flowing liquid during compressor operation.
- 🔴 Hot condenser grille at the back of the refrigerator (it should be warm, but not hot over the entire area).
- 🔴 The compressor runs “idle” and gets very hot.
⚠️ Attention: Freon used in modern refrigerators is safe for humans in small quantities, but upon contact with an open fire it can form toxic compounds. Do not use open fire to search for leaks!
If a leak is confirmed, simple refueling will not work. The technician must find the location of the damage, repair it, and only then recharge the system. In case of corrosion of the foamed evaporator (inside the wall), it is often necessary to install an external evaporator (“crying” on the back wall inside the chamber), since restoring the factory circuit is not economically feasible.
Problems with the compressor and start relay
The compressor is the heart of the refrigerator, creating pressure for circulation refrigerant. If one chamber does not freeze and the compressor operates intermittently, the problem may lie in a decrease in its performance. Over time, the piston group wears out, and the unit cannot create sufficient pressure to pump freon through the entire circuit.
Often the culprit for unstable operation is start relay. This small element is responsible for starting the compressor engine. If the relay is faulty, the compressor may hum but not start, or run in short cycles without having time to cool the chambers. In some cases, the relay may stick, causing the motor to run continuously, which leads to overheating and the thermal relay turning off.
Diagnostics of the compressor requires measuring the outlet pressure and current. At home, you can check only external signs: if the engine is hot, vibrates strongly or makes a metallic knock, its resource is most likely exhausted. Replacing a compressor is a complex procedure that requires evacuation of the system and precise filling with oil and freon.
Is it possible to replace a compressor yourself?
Theoretically, it is possible if you have the skills to work with refrigeration equipment, a burner and a vacuum pump. However, without a professional tool, it is impossible to properly solder the tubes and remove moisture from the system, which will lead to rapid re-breakage.
It is also important to check the integrity of the motor windings. With an interturn short circuit, the compressor can operate, but consume increased current and quickly heat up, knocking out the circuit breaker. In this case, operating the refrigerator is dangerous by fire.
Faults in the defrost system and sensors
In refrigerators with the system No Frost Proper operation of the defrost system is critical. It consists of a heater, a defrost sensor (thermostat) and a timer (or electronic module). If this unit fails, the evaporator becomes covered with a “coat” of ice, which blocks air circulation. As a result, the fan circulates air, but there is no cold in the chambers.
Most often, the defrost heating element or the sensor that records the evaporator temperature breaks down. If the sensor is stuck in the cold position, the heater will never turn on and ice will build up until it blocks the ducts. If the sensor shows “warmth”, the heater will work constantly, melting the plastic parts.
Symptoms of a defrost system malfunction:
- ❄️ A layer of ice or snow is visible on the back wall of the refrigerator compartment.
- ❄️ The fan makes noise or stops due to icing of the blades.
- ❄️ The refrigerator works without interruption, but the temperature does not drop.
- ❄️ After defrosting, the equipment works normally for several days, then the problem returns.
⚠️ Attention: Do not try to break off the ice with a knife or sharp objects! This may damage the evaporator and cause freon leakage. Use only warm air (hair dryer) or natural thawing.
For diagnostics, technicians use a multimeter, checking the resistance of the heating element and sensor. Replacing these elements usually does not require opening the circuit and is relatively inexpensive. It is also important to check the integrity of the wiring going to the heater, as it often burns out or breaks.
Clogged capillary tube and other mechanical problems
The capillary tube is a narrow channel in which throttling (a sharp drop in pressure) of the refrigerant occurs. Due to its small diameter, it becomes clogged with oil oxidation products, moisture or debris remaining after poor-quality repairs. The blockage can be complete or partial.
If the blockage is partial, the refrigerator may freeze, but worse than usual. If the blockage is complete, the circulation of freon stops. A typical sign of a blockage is that the compressor is running, the condenser is cold (or warm only at the outlet of the compressor), and the evaporator is not cooling. Sometimes you can hear a characteristic gurgle that ends abruptly.
Mechanical damage also includes:
- 🔧 Pinching of tubes during transportation or installation of the refrigerator.
- 🔧 Malfunction of the air flow control damper (in dual-circuit systems).
- 🔧 Failure of the blower fan (in No Frost), which simply stopped spinning.
- 🔧 Depressurization of the door seal, due to which warm air constantly enters the chamber.
To remove the blockage, professional high-pressure nitrogen purging and replacement of the filter-drier are required. It is impossible to carry out this procedure independently without special tools. If the problem is in the fan, you can often replace it yourself by selecting an analogue in size and connector.
Comparison table of symptoms and probable causes
For ease of diagnosis, we have compiled a summary table that will help compare the observed symptoms with the most likely causes of the malfunction. Remember that an accurate diagnosis can only be made by a specialist with equipment.
| Symptom | Probable cause | Difficulty of repair | Refueling need |
|---|---|---|---|
| The compressor works without stops, no cold | Freon leak or blockage | High | Yes |
| The refrigerator turns on rarely, the chambers are warm | Thermostat malfunction or sensor | Low | No |
| Humming, clicking, no start | Start relay or compressor | Medium/High | No/Yes |
| Ice on the back wall, weak airflow | Failure of the defrost system (No Frost) | Average | No |
| One chamber freezes, the other does not | Valve or damper malfunction | Average | Depends on the model |
The table shows that the symptoms may overlap. For example, a lack of cold can be caused by either a leak or broken electronics. This is why comprehensive diagnosis is important. Do not rush to throw away the equipment or buy a new one - in many cases, repairs are much cheaper.
Frequently asked questions (FAQ)
Is it possible to operate refrigerator, if one chamber does not work?
Short-term operation is possible, but undesirable. If the refrigerator compartment is not frozen, food may spoil. If there are problems with the freezer, the compressor will work hard trying to reach the temperature, which will lead to overheating and eventual failure. It is better to turn off the device before the technician arrives.
How long does it take to repair a refrigerator?
Replacing sensors, relays or fans takes 1-2 hours. Repairs related to leak detection and refilling can take from 3 to 5 hours, since it takes time to evacuate the system. If rare spare parts are needed, the period may increase to several days.
Why did the refrigerator start working normally after defrosting, but after a week stopped working again?
This is a classic sign of a clogged capillary tube or a malfunction of the defrost system. Ice that forms in the system melts when defrosted and temporarily clears the blockage or allows the fan to spin. But when operation resumes, the moisture freezes again in a bottleneck, blocking the system.
Is it worth repairing an old refrigerator or buying a new one?
If the refrigerator is more than 10-12 years old and requires a compressor replacement or complex circuit repair, it is often more economical to buy new equipment. If the problem is in the sensor, relay or fan, repair is advisable even for older models.
Is it dangerous to breathe freon vapors during a leak?
Modern freons (R134a, R600a) in small quantities contained in a household refrigerator are not toxic to humans. However, R600a (isobutane) is an explosive gas. If you smell gas or suspect a leak in models with this refrigerant, you must ventilate the room and do not turn on electrical appliances that create a spark.