The appearance of ice on the back wall of the refrigerator compartment or the formation of a “snow coat” in the freezer compartment often indicates a malfunction of the defrost system, the central element of which is evaporator. This heat exchange unit is responsible for cooling the air circulating inside the chambers, and if it does not operate correctly, the refrigerator stops freezing or begins to consume an excessive amount of electricity.
Independent replacing the evaporator is a complex technical process that requires not only skills in working with power tools, but also understanding of the principles of operation of the refrigeration circuit. Unlike simply replacing a light bulb or seal, it is critical to maintain tight connections and correctly connect temperature sensors to avoid repeated breakdowns.
Before taking active steps, you need to make sure that the problem lies precisely in mechanical damage to the tubes or complete failure of the heat exchanger, and not in a blockage capillary system or compressor malfunction. In this article, we will analyze in detail the stages of dismantling the old and installing a new unit, paying special attention to the nuances of working with the system No Frost and a crying evaporator.
⚠️ Attention: If you plan to replace the evaporator due to a freon leak, keep in mind that simply soldering a new part is not enough. The system requires evacuation and charging with a strictly defined type and weight of refrigerant, which is only possible with the use of professional equipment.
Diagnostics and preparation of the workplace
The first step before starting any work is the complete diagnostics current condition of the refrigerator. Users often mistake a malfunction of the fan or defrost heating element for a breakdown of the evaporator, so a visual inspection and “listening” to the operation of the unit will help avoid unnecessary disassembly. If you hear the hum of the compressor, but no cold is generated, or oily spots are visible under the refrigerator, the likelihood of damage to the evaporation circuit is high.
Preparation of the workplace is no less important than the repair process itself. You will need free space around the refrigerator, good lighting and a set of specialized tools. To work with modern refrigeration equipment, such as Indesit or Atlant, a standard set of screwdrivers may not be enough.
Be sure to turn off the power to the device before starting work. Even a short-term touch of the bare contacts of sensors or a energized fan can lead to electric shock or failure of the electronic control module.
- 🛠️ Tools: a set of screwdrivers (phillips and flat-head), socket wrenches, insulation stripping knife, side cutters.
- ❄️ Consumables: new evaporator (original or high-quality analogue), solder for copper pipes, nitrogen for purging (if soldering is planned).
- 🧤 Protection: work gloves (the metal edges of the panels can be sharp) and safety glasses.
Removing internal equipment and panels
The process of accessing the evaporator is radically different depending on the type of refrigerator: with a system No Frost or with a crying evaporator. In No Frost models, the heat exchanger is usually hidden behind the back panel in the freezer, while in classic models it can be built into the wall or located behind a plastic box in the refrigerator compartment.
Start by completely emptying the chambers of food and removable shelves. In a freezer, it is often necessary to remove the drawers, runners, and fasteners that hold the back wall in place. Be careful with plastic latches: at low temperatures, the plastic becomes brittle and can easily break if handled carelessly.
After removing the decorative panels, access to the insulating materials and directly to the evaporation unit will open. At this stage, it is important not to damage the wiring going to the temperature sensors and the fan, since their restoration will require additional soldering and insulation.
☑️ Preparation for disassembly
If you find that access to the evaporator mounting screws is blocked by a layer of polyurethane foam or a complex design of air ducts, do not rush to cut insulation with a knife. Evaluate the design: it may be necessary to dismantle the entire internal box, which will preserve the integrity of the thermal insulation.
Removing the old evaporator and preparing the niche
Dismantling the heat exchanger itself is the most critical stage. In systems where the evaporator tubes are mounted into the housing wall (foamed), replacement is carried out by installing an overhead evaporator (“crying” type) or cutting out part of the wall, which requires high qualifications. If you have a model with an open arrangement, like many refrigerators LG or Samsung, the task is simplified to unscrewing the fastening plates.
Before disconnecting the copper tubes from the compressor or filter-drier, it is necessary to bleed off the remaining refrigerant in a well-ventilated area. A sudden rupture of tubes under pressure can lead to oil splashing and moisture entering the circuit, which is strictly unacceptable.
After physically removing the old assembly, it is necessary to thoroughly clean the niche from the remains of old insulation, dirt and oxides. The surface to which the new evaporator will contact must be smooth and clean to ensure maximum thermal contact area.
⚠️ Attention: Never use sharp metal objects to chip ice or clean the surface of the evaporator. A puncture of the tube will lead to an immediate leak of freon and will require expensive repairs with soldering.
If the new evaporator has geometric dimensions different from the original, careful adjustment of the mounting holes or the use of additional adapters may be required. The main thing is to ensure that there are no gaps between the tubes and the chamber wall or fan.
Technical characteristics and types of evaporators
When selecting and installing a new part, it is critical to take into account its technical parameters. An evaporator that is unsuitable in power or size will lead to incorrect operation of the thermostat and compressor. Below is a table that helps distinguish the main types of components for popular systems.
| System type | Location | Installation features | Frequent faults |
|---|---|---|---|
| No Frost | Freezer compartment (for panel) | Hidden, with a blowing fan | Freezing, leaks in solder joints |
| Crying | Rear wall of the refrigerator compartment | Open or foamed in case | Corrosion, mechanical damage |
| Full No Frost | Separately in each chamber | Two independent circuits | Non-synchronous operation of sensors |
| Low Frost | Under the bottom of the freezer | Simplified circulation system | Clogged drainage, uneven cold |
Particular attention should be paid to the material of manufacture. Aluminum evaporators are cheaper, but are susceptible to corrosion and are more difficult to solder. Copper or bimetallic (aluminum-copper) analogues last longer and are easier to repair if necessary.
Is it possible to use a universal evaporator?
Yes, there are universal models with a reserve length of tubes. However, their efficiency may be lower than the original ones, and installation will require careful laying of the turns so as not to disrupt air circulation.
Installation and connection of a new unit
Installation of a new evaporator is carried out in the reverse order of dismantling. If the design involves soldering copper joints, use a torch with a narrow torch and be sure to use solder containing silver to ensure tightness and strength of the seam. The soldering area must be cleaned to a shine and treated with flux.
When installing the pipes, try not to bend them at an angle of less than 90 degrees, as this can lead to a break in the internal lumen and disruption of the refrigerant circulation. Fix the tubes to the body using standard clips or heat-resistant tape.
An important step is connecting the electrical part: temperature sensors, defrost heating elements and fan. Check the integrity of the wires and the reliability of the contacts. Oxidized connectors must be cleaned or replaced, as they can cause false temperature readings.
- 🔍 Check: Make sure that the defrost heating element fits tightly to the drainage channel.
- 🔌 Contacts: All electrical connections must be insulated with heat shrink.
- 🌬️ Ventilation: The fan blades should not touch the housing or ice.
Completion of work and test run
After installing all components and checking the electrical connections, you can begin assembling the panels. Do not completely block access to the compressor until the first start - this will allow you to control its temperature and the absence of oil leaks.
Turning on the refrigerator after replacing the evaporator, if soldering and charging with freon has been carried out, requires time to stabilize the pressure in the system. For the first 2-3 hours, the unit can operate in enhanced mode, which is normal.
Temperature control measurements should be made no earlier than after 6-8 hours of operation. In the freezer compartment the temperature should drop to -18°C, and in the refrigerator compartment - to +4...+5°C. If the indicators are not achieved, there may be air left in the system or the amount of refrigerant is selected incorrectly.
⚠️ Attention: If, after replacing the evaporator, the compressor runs continuously for more than 12 hours without turning off and does not gain temperature, immediately turn off the device. This may indicate a blockage in the capillary system or improper filling.
If the test period is successful, you can put all the drawers and shelves in place and load the products. Regularly check the condition of the rear wall in the first weeks of operation for the appearance of excess moisture or ice.
Is it necessary to evacuate the system when replacing evaporator?
Yes, if the circuit was depressurized (soldering), vacuuming is mandatory. It removes air and moisture vapor that can freeze in the capillary tube and cause blockage, as well as oxidize the compressor oil.
Is it possible to replace the evaporator with an analogue from another brand?
Technically possible if the dimensions, power and type of refrigerant are the same. However, it is better to use original spare parts or certified analogues, since a discrepancy in characteristics can lead to incorrect operation of the automation.
Why does the refrigerator freeze less easily after replacing the evaporator?
There may be several reasons: insufficient amount of freon, the presence of air in the system, loose fit of the evaporator to the chamber wall, or a malfunction of the blower fan. Repeated diagnostics are required.
How often should the evaporator in the refrigerator be changed?
The evaporator is a part that does not have a limited service life. It is replaced only in case of mechanical damage (leakage) or critical corrosion. With careful operation, it lasts as long as the refrigerator itself.