How the refrigerator works: analysis of the device based on photos with explanations

Have you ever wondered what is hidden behind the plastic panels of your refrigerator? Why does it hum, why does it freeze, and why does it sometimes stop working? In this article we let's look at the refrigerator's structure from the photowill show the key nodes and explain how they interact. You will see where the compressor is located, what the evaporator looks like from the inside, why condensation forms on the back wall and what to do if the refrigerator has become worse at cooling.

We will not burden you with complex technical terms - instead we will show real photos the insides of refrigerators of different brands (Atlant, Samsung, Indesit, LG) so that you can compare them with your model. We’ll also tell you what it is parts most often break and how to determine it by external signs. If you are planning a repair or just want to understand how the equipment you use every day works, this article is for you.

1. The main components of the refrigerator in the photo: what is where

Let's start with the “anatomy” of the refrigerator. The photographs below show the key elements that are in any model —whether it is old ZIL or modern Liebert with the system No Frost.

📌 Compressor —"heart" refrigerator. Located at the bottom of the back (usually right or center). In the photo it looks like a black barrel with pipes and a start relay. It is he who pumps the refrigerant (freon) through the system, creating cold.

📌 Condenser is a grid of tubes on the back wall. Here the freon is cooled, releasing heat to the environment. If the condenser is dusty, the refrigerator will overheat and freeze worse.

📌 Evaporator - is located inside the refrigerator or freezer compartment (sometimes hidden under a plastic panel). In models with No Frost the evaporator is hidden behind the back wall and is blown by a fan.

📌 Thermostat (or electronic control unit) - regulates the temperature. In mechanical models it looks like a box with an adjustment knob, in electronic ones - a board with sensors.

• 🔧 Compressor - a black cylinder with tubes, usually covered with thermal insulation.
• 🌀 Condenser - a thin coil tubes, often covered with dust.
• ❄️ Evaporator —aluminum or copper tubes with fins (in the freezer may be covered with frost).
• 📊 Thermostat —a plastic box with a handle or display (in modern models).

The photo below shows a typical back wall of a refrigerator Atlant (model MXM-1835). You can see how the compressor is connected to the condenser by tubes, and at the bottom there is a drainage system for removing condensate.

Where to look for the serial number of the refrigerator?

Usually it is located on a sticker inside the refrigerator compartment (on the left on the wall), on the back wall of the case or under the bottom door. In some models (for example Samsung RB30J3000WW), the number is duplicated on the box and in the warranty card.

2. The principle of operation of the refrigerator: how freon creates cold

Now let's figure it out how these parts interactto maintain a low temperature. It all starts with the compressor:

1. Freon compression: The compressor sucks in gaseous refrigerant (freon) and compresses it, increasing the pressure and temperature.
2. Cooling in the condenser: Hot freon enters the condenser (grid on the back wall), where it cools and turns into liquid.
3. Expansion in the evaporator: Liquid freon passes through a capillary tube (or thermostatic valve) and enters the evaporator. Here it expands, boils and absorbs heat from the chamber.
4. The cycle repeats: Freon again becomes a gas and returns to the compressor.

🔹 Important: In refrigerators with No Frost a fan has been added that evenly distributes cold air throughout the chamber. This prevents the formation of frost, but requires more energy.

⚠️ Attention: If the refrigerator begins to freeze worse, but the compressor works without stopping, the problem may be freon leak or a clogged capillary tube. It is impossible to fix this on your own - you need a specialist with refilling equipment.

3. Photo of the evaporator: why it becomes covered with ice or frost

The evaporator is the part of the refrigerator where cold is directly formed. In models with drip system (for example, Indesit DF 4180) it is located on the back wall of the refrigerator compartment and looks like a plastic panel with tubes. In the freezer, the evaporator is often open and covered with frost.

The photo below shows the evaporator of the refrigerator freezer LG GA-B489YQZL. You can see how the tubes are frozen with ice. This is normal, but if the ice builds up too quickly (thicker than 5-7 mm), it means:

• 🔌 Faulty thermostat (does not turn off the compressor in time).
• 🚪 Problems with door seal (warm air enters).
• 🌀 Clogged drainage system (water does not drain, freezes).

In refrigerators with No Frost the evaporator is hidden behind a plastic panel, and you will not see ice on it. Instead, the system defrosts itself every 8–12 hours using a heating element. If defrosting does not work, ice will accumulate inside and you will notice:

• ❄️ Constant fan noise (ice interferes with the blades).
• 💨 Weak flow of cold air from the vents.
• 🔥 The compressor works almost without stopping.

Check the temperature in the freezer (should be -18°C or lower)|

Inspect the back wall for ice (in drip models)|

Listen to the fan (in No Frost - should stop periodically)|

Check the drainage hole (if it is clogged)-->

4. The compressor in the photo: what it looks like and why it breaks

The compressor is the most expensive and important part of the refrigerator. In the photo it looks like a black barrel with protruding tubes and electrical contacts. In modern models (Samsung RL-44, Bosch KGE39XW2AR), the compressor is often closed with a protective casing or foam insulation.

🔧 Typical compressor breakdowns:

• 🔌 Interturn short circuit —the compressor hums, but does not start (protection is triggered).
• 💥 Open circuit windings —the refrigerator does not turn on at all.
• 🛠️ Wear of the piston group —the compressor works, but does not create the required pressure (the refrigerator does not freeze well).
• 🔋 Faulty starting relay —clicks are heard, but the compressor does not start.

⚠️ Attention: If the compressor overheats (the housing is too hot, there is a burning smell from it), immediately unplug the refrigerator! This may cause a fire. Reasons for overheating:

• Clogged capacitor (dust, dirt).
• High voltage in the network (more than 240 V).
• Fan malfunction (in models with No Frost).

The photo below shows a refrigerator compressor Beko CN 325120 with burnt relay contacts. This is a typical sign of voltage surges or wear of parts.

5. Thermostat and electronic unit: how they control the temperature

The thermostat (or electronic controller in modern models) is the “brain” of the refrigerator. It monitors the temperature and turns the compressor on/off. data-i="175">) the thermostat looks like a box with an adjustment knob (usually inside the refrigerator compartment).Birusa 101, Nord 242) The thermostat looks like a box with an adjustment knob (usually inside the refrigerator compartment).

In electronic models (Samsung RB-30 J3200EF, LG GA-B409SLGL, instead of a thermostat, a control board with sensors is used. It is more accurate, but also more vulnerable to power surges.

📌 Signs of a malfunction. thermostat/control unit:

• 🌡️ The compressor does not turn off (the refrigerator “freezes” the food in the refrigerator compartment).
• ❄️ The compressor does not turn on at all (it is warm in the chamber).
• 🔄 The temperature fluctuates (then -5°C, then +10°C for no apparent reason).
• 💡 An error flashes on the display (for example, Er IF or Er FF y Samsung).

⚠️ Attention: If you decide to replace the thermostat yourself, be sure to unplug the refrigerator i discharge the capacitors (they can store dangerous voltage!) In electronic models, it is better not to take risks - incorrect connection of the board can damage the compressor.

The photo below shows the refrigerator control board Indesit BIAA 13 with a burnt resistor. This is a typical consequence of a voltage surge. In such cases, you need to replace the board or solder damaged elements (if you know how to work with a soldering iron).

How to check the thermostat with a multimeter?

Disconnect the thermostat from the wires and switch the multimeter to resistance testing mode At room temperature between pins 3 and 4 (or 2 and. 3, depends on the model) the resistance should be close to 0 Ohm. If it shows a break, the thermostat is faulty.

6. Condenser and fan: why the refrigerator is heating up at the back

The condenser is the same grille on the back wall of the refrigerator that is always warm, but many users are scared, thinking that the appliance is overheating. this normal process: here the freon is cooled, giving off heat to the environment.

🔹 What should be alert:

• 🌡️ Condenser hot as an iron (more +60°C) - perhaps the compressor is working for wear.
• 🧹 The grille is clogged with dust - this impairs heat transfer and leads to overheating.
• 💨 The fan does not spin (in models s No Frost) - check if it is blocked by ice.

In refrigerators with No Frost an additional fan is installed that blows on the condenser and evaporator. If it breaks, the refrigerator will not cool well, and the compressor will overheat. data-i="206">with iced blades (defrost required). Atlant MXM 2835-080 with iced blades (defrost required).

🛠️ How to clean the condenser:

1. Unplug the refrigerator.
2. Carefully move it away from the wall (you need room to work).
3. Use a vacuum cleaner or soft brush to remove dust from the grill.
4. Wipe with a damp cloth (without detergents!).

7. Drainage system: why there is a puddle under the refrigerator

Water under the refrigerator is one of the most common problems. In 90% of cases, it is associated with the drainage system. condensate from the refrigeration chamber. In normal mode, water flows through a special groove into a container on the compressor and evaporates.

🔧 Causes of leaks:

• 🕳️ The drainage hole is clogged (inside the refrigeration chamber, usually on the back wall).
• 💧 Crack in the drainage tube (on the back wall).
• 🧊 The drainage channel is frozen (in models with No Frost).
• 🚰 The condensate container is shifted or cracked.

⚠️ Attention: If water appears inside the freezer compartment, this is a sign of a malfunction of the defrost system (in No Frost) or a freon leak. In this case, diagnostics by a specialist is needed.

In the photo below there is a drainage hole. refrigerator Samsung RL-33, clogged with crumbs and mold. You can clean it using a syringe with warm water or wire (carefully so as not to damage the plastic!).

8. Frequent faults from the photo: how to diagnose a breakdown

Many refrigerator breakdowns can be identified by external signs. collected photos of typical faults and explained what they mean.

📸 1. The compressor does not start, but the light inside is on

🔹 Cause: The starting relay or the compressor itself is faulty.

🔹 Photo: Relay with burnt contacts or a compressor without signs of operation (does not vibrate, does not heat up).

📸 2. The refrigerator freezes, but does not turn off

🔹 Cause: The thermostat or temperature sensor is broken.

🔹 Photo: Ice on the back wall of the refrigerator compartment (in drip models) or frozen evaporator (in No Frost).

📸 3. Strong noise or vibration

🔹 Cause:

• The compressor fastenings are loose.
• The fan (No Frost) touches the ice.
• A foreign body has entered condenser.

📸 4. The refrigerator does not cool, but the compressor works

🔹 Cause: Freon leak or capillary tube clogged.

🔹 Photo: The condenser is cold (should be warm), the evaporator is not freezes over.

⚠️ Attention: If you see oil on the floor under the refrigerator this is a sign of a serious freon leak (it comes out along with the oil from the compressor. In this case, you need to immediately turn off the refrigerator and call a technician.

FAQ: Frequently asked questions about the operation of the refrigerator

Why is the refrigerator humming but not freezing?

This is a typical symptom freon leaks or clogging in the capillary systemThe compressor is working, but the refrigerant is not circulating. malfunction thermostatic valve (in models with No Frostit is impossible to fix the breakdown on your own - you need a technician with refilling equipment.

Is it possible to replace the compressor yourself?

Theoretically yes, but this a complex and dangerous procedurewill require:

• Special tool for inserting tubes.
• Vacuum pump for pumping out the system.
• Freon cylinder and manometric manifold.
• Knowledge on soldering copper pipes.

Errors during replacement can lead to repeated leakage or failure of the new compressor. If you are not an experienced technician, it is better to entrust this to professionals.

Why does ice form on the back wall of the refrigerator (in No Frost models)?

In the system No Frost ice on the evaporator should thaw automatically every 8–12 hours. If this does not happen, check:

• 🔌 The defrost heating element (the contacts are burnt out or oxidized).
• 🌡️ The defrost sensor (does not measure the temperature correctly).
• ⏱️ Defrost timer (does not supply signal to turn on the heating element).

If the problem is not corrected, the ice will block the fan and the refrigerator will stop freezing.

How often should you defrost a refrigerator with No Frost?

Manufacturers claim that refrigerators No Frost do not need defrosting. However, in practice it is recommended:

• 🧊 Defrost once a year for hygienic cleaning (remove mold, odors).
• 🔧 Check the drainage hole (it can even become clogged c No Frost).
• ❄️ If ice builds up in the freezer, this is a sign of a malfunction, not the norm.

Why does the refrigerator get very hot on the sides?

The side walls of the refrigerator can be warm if:

• 🔥 The condenser is located not at the back, but on the sides (for example, in models Liebert or some Samsung).
• 🌡️ The room is hot (above +30°C), and the refrigerator is working at its limit.
• 🚪 The door is not closed well (seal worn out).

If the walls are not just warm, but hotcheck:

• Fan operation (in No Frost).
• Cleanliness of the condenser.
• Network voltage (should be 220–230 V).