The situation when the refrigerator Bosch stops freezing, and a “coat” of ice grows on the back wall of the chamber, often indicates a malfunction of the defrost system. In models with technology No Frost an evaporator hidden behind a plastic panel is responsible for air cooling. If the heating element or defrost sensor fails, the ice blocks the circulation of air flow and the food begins to deteriorate. To fix the breakdown, you need to get to the heat exchanger, which requires careful disassembly of the inside of the unit.
Independent dismantling of this unit is a procedure available to a home craftsman, but it requires strict adherence to the sequence of actions. Incorrect work with fragile plastic or damage to aluminum tubes can lead to a freon leak, which will turn a simple repair into an expensive refill of the circuit. It is critically important not to use sharp objects to chip the ice inside the chamber, since a breakdown of the evaporator tube will lead to the complete loss of the refrigerator. In this article we will analyze in detail the process of removing the evaporator, paying attention to the nuances of the design of household appliances Bosch.
Before starting work, you need to prepare your workplace and tools. You will need not only a technical mind, but also a minimum set of screwdrivers, as well as a hair dryer to speed up the defrosting process. Remember that rushing to remove plastic fasteners often ends in breaking the latches, so proceed methodically. Below we will look at the preparation steps that cannot be ignored.
⚠️ Attention: Before starting any disassembly work, be sure to disconnect the refrigerator from the power supply. Working with live electrical components is prohibited by safety regulations.
Necessary tools and preparation for work
The success of the operation to remove the evaporator directly depends on the quality of preparation. You will need a standard DIY kit, which many people have. First of all, check the presence of a Phillips screwdriver, since most screws in the design Bosch have a corresponding slot. A small flat-head screwdriver may also be useful for carefully snapping off the plastic plugs.
Pay special attention to the issue of defrosting. If ice has accumulated in the freezer, do not remove it mechanically. The best solution would be natural defrosting for several hours or using a household hair dryer at the lowest temperature. A hair dryer allows you to speed up the process, but you need to direct the hot air stream carefully so as not to deform the thin plastic of the inner lining.
- 🔧 Phillips and flat-head screwdrivers for removing fasteners.
- 🌡️ Household hair dryer for carefully defrosting ice.
- 🧼 A container and rags for collecting melt water.
- 🔦 A flashlight for illuminating hard-to-reach places.
Also prepare a container to collect the water that inevitably forms when the ice melts. Cover the floor in front of the refrigerator with towels or rags to avoid damaging the floor covering. If you have a multimeter, you should also keep it on hand for subsequent diagnostics of the heating element and thermostat, although it is not required for the removal process itself.
Design features of the evaporator in Bosch refrigerators
Refrigerators Bosch, like many modern models, are equipped with a system No Frostwhere the evaporator is not located in the main chamber, and in a hidden compartment behind the back wall of the freezer. The air circulates through this heat exchanger, is cooled and supplied to the chambers by a fan. This design is effective, but makes the node difficult to access. The plastic panel covering the evaporator is attached to screws and plastic latches, which require careful handling.
Inside the hidden box there are not only aluminum heat exchanger tubes, but also a heating element (heating element), temperature sensors and a capillary tube. All these elements are closely intertwined. When removing the panel, it is important not to damage the sensor wiring, which is often short and strained. The design may vary depending on the specific series Bosch, but the general principle of the layout remains similar.
The aluminum from which the evaporator is made is very soft and susceptible to corrosion upon contact with moisture and air if the protective layer is damaged. That is why you should not use a knife or other sharp tools when cleaning or defrosting. Over time, even a microscopic scratch can turn into a fistula through which the refrigerant evaporates.
Why does ice block the operation of the refrigerator?
Ice, growing on the evaporator, blocks the channels through which the fan drives cold air. As a result, the chamber becomes warm, and the compressor works without interruption, trying to compensate for the loss of cold, which leads to its overheating and failure.
The process of dismantling the rear panel of the freezer
The first stage will be the release of the freezer. Remove all drawers, shelves and containers. If the drawers are frozen and cannot be removed, let them thaw a little or gently heat the plastic with a hairdryer, but do not overdo it. After the chamber is empty, you will see the back wall, which hides the desired unit.
Carefully inspect the wall for the presence of fasteners. In refrigerators Bosch screws are often hidden under decorative plugs or plastic caps. They need to be carefully pryed off with a flat screwdriver. Remove all visible screws. Sometimes the fasteners may be located deep in a niche or under the fastening elements of the drawers, so be careful.
After removing all the fasteners, the panel is not always removed immediately. It can be held on by latches around the perimeter. Start by prying them off from the bottom or side using a plastic card or a flathead screwdriver wrapped in cloth to avoid scratching the glossy plastic. Move gradually, releasing the latches in a circle.
☑️ Checklist before removing the panel
When the panel is removed, you will have a view of the evaporator. Don't rush to touch it. Inspect the condition of the ice. If ice remains, continue defrosting. An attempt to remove the evaporator or disconnect the wires in the presence of ice may lead to the breaking of the plastic elements securing the wires.
Disconnecting the wires and fastening elements
Now that access is open, you need to disconnect the electrical components. Defrost sensors and heating elements are attached to the evaporator. The wires from them go to connectors, which are usually located next to the fan or at the top of the niche. The connectors may be tight; they need to be unlocked by pressing the latch and only then pulled.
Pay attention to the fastening of the heat exchanger itself. It can be screwed to the back wall of the refrigerator or secured with clamps. In some models Bosch the evaporator is simply inserted into the grooves and is held in place due to the tight fit and insulation pressure. If you see screws holding the aluminum rolls, carefully unscrew them.
Take special care with the capillary tube. She is thin and fragile. It is often secured with electrical tape or plastic clamps to the evaporator tubes. Don't pull on it. If you need to remove the evaporator completely (for example, for replacement), the tube must be released last, acting as delicately as possible.
| Element | Type of fastening | Risks during removal | Tool |
|---|---|---|---|
| Rear panel | Screws + latches | Plastic breakage | Phillips screwdriver |
| Sensors | Connectors | Breakage wires | Fingers/tweezers |
| Defrost heating element | Brackets/screws | Damage to nichrome | Screwdriver |
| Evaporator | Grooves/clamps | Tube breakdown | Key/pliers |
If the wires prevent full access, do not try to bend them at an unnatural angle. It is better to temporarily unscrew the additional fasteners that hold the wire harnesses in order to gain free access to the assembly.
Removing the evaporator and diagnosing faults
After disconnecting all communications, you can begin to remove the evaporator itself. Gently pull it towards you, slightly rocking it from side to side if it fits snugly in the grooves. Movements should be smooth. If you feel resistance, stop and check that all fasteners and wires are disconnected.
The removed heat exchanger should be inspected. Visually check the integrity of the aluminum tubes. Look for traces of oil - they may indicate microcracks. Also inspect the defrost heating element: it should not have ruptures or swelling. Often the cause of icing lies in a burnt-out heater or a stuck timer, and not in the evaporator itself.
⚠️ Attention: If you plan to install the old evaporator back, make sure it is completely dry. Moisture inside the insulation can lead to repeated rapid icing and corrosion.
To diagnose the heating element, use a multimeter in continuity mode. The resistance of a working heating element is usually several hundred Ohms (depending on the power). If the device shows a break (one or infinity), the heating element must be replaced. Temperature sensors are checked for changes in resistance when the temperature changes (heating in the hands).
Assembling the system and checking for leaks
Assembly is in progress in the reverse order of disassembly. Reinstall the evaporator, making sure it fits snugly into the grooves. Connect all electrical connectors until you hear a click. Secure the wires so that they do not touch the moving parts of the fan and are not pinched.
Install the rear plastic panel. First, engage the top latches, then gradually press the bottom until you hear a characteristic click along the entire length. Tighten all screws. It is important not to overtighten the screws in the plastic, so as not to strip the threads or crack the material.
After assembly, turn on the refrigerator. During the first hours of operation, listen to the noise of the fan - it should work smoothly, without any extraneous sounds. Check if cold starts to enter the chamber. If you have changed heating elements or sensors, it makes sense to check the first defrost cycle to make sure that the system is working correctly.
If after turning on the refrigerator runs quietly and freezes, then the procedure was successful. However, keep an eye on the condition of the back wall of the freezer during the first week. The appearance of frost in the wrong places may indicate a loose fit of the panel or residual moisture.
Frequently asked questions (FAQ)
Is it possible to remove the evaporator without completely defrosting the refrigerator?
It is strictly not recommended. Ice hiding the fasteners and wires can cause the plastic to break when attempting to forcefully remove it. In addition, melting water can short-circuit the contacts of the electronics.
How often do you need to defrost a Bosch No Frost refrigerator?
The system No Frost does not require regular manual defrosting to remove ice, as this happens automatically. However, once a year it is recommended to carry out preventive defrosting and cleaning for hygiene and checking the drainage hole.
What to do if, after assembly, the refrigerator hums more than usual?
Check whether the fan blade is touching ice or wires. Also make sure that the back panel is firmly in place and does not resonate. If the compressor is humming, this may be a sign of other malfunctions.
Is it possible to replace the heating element with an analogue from another model?
Yes, if the dimensions, power (Watts) and voltage (Volts) match. The main thing is that the heating element physically fits into place and effectively warms up the evaporator.