Looking for a heat exchange element inside household appliances is often the first step in diagnosing cooling problems. Owners of German equipment Bosch are faced with the need to find this part when ice appears, extraneous noise or a complete absence of cold. Understanding where exactly it is located evaporatorallows you to make a decision about independent repairs or calling a specialist.
The design of modern models differs significantly from old Soviet analogues. If in classic “drip” systems everything was relatively transparent, then the technology No Frost hides the main components behind decorative panels. In this article, we will analyze in detail the architecture of refrigeration chambers and indicate the exact locations of radiators for different series of equipment.
The main task of this unit is to absorb heat from the internal space of the chamber, which leads to cooling of the air. Depending on the model of your unit, the refrigerant evaporation process may occur in a hidden niche or be partially visible. To accurately diagnose a malfunction, you must clearly understand the device of your specific modification Bosch.
Design features of the Bosch cooling system
The brand's engineering philosophy Bosch involves a high degree of integration of components. The evaporator here is not just a curved tube, but a complex aluminum radiator with fins, often enclosed in a plastic housing. In models with the system No Frost it is hidden behind the back wall of the freezer, where access is limited by several layers of insulation.
It is important to understand the difference between single-compressor and double-compressor schemes. The former often use one main evaporator located in the freezer, and cold is supplied to the refrigerator compartment through special channels using fan. Secondly, two independent circuits can be installed, which changes the logic of search and repair.
⚠️ Attention: In models with a system LowFrost or VarioFresh the design may differ from the classic No Frost. Before starting work, be sure to check the technical documentation for your series, since the location of fasteners may vary.
The materials used by the manufacturer require careful handling. Aluminum tubes can be easily damaged with a sharp tool, and restoring the tightness of the system requires special equipment. Therefore, a visual inspection should be carried out with the utmost care, without using excessive force.
Location in models with the No Frost system
In the vast majority of modern refrigerators Bosch with technology No Frost (or Total No Frost) the main heat exchanger is located in freezer. It is hidden behind a plastic panel on the back wall. To get to it, you need to completely defrost the unit and remove the internal lining.
The access process usually involves removing shelves, drawers and mounting screws hidden under plugs. After removing the back panel, you will see an evaporator block surrounded by thermal insulation. This is where a “fur coat” most often forms if the defrost heating element or sensor is faulty.
- ❄️ The main radiator is located vertically along the back wall of the freezer compartment.
- 🔧 Access to it is blocked by a plastic cover secured with screws and clips.
- 🌬️ Next to the evaporator there is always a fan that blows cold air.
- 💡 Under the evaporator there is a tray for collecting melt water and a tray for the heating element.
It is worth noting that in some modifications SuperFrost there may be an additional circuit or modified geometry of the air ducts. However, the principle of hidden placement in the freezer remains unchanged for the entire No Frost line.
Why can’t you scrape the ice with a knife?
Mechanical damage to the aluminum evaporator tubes will lead to an instant release of refrigerant. Repair in this case will require expensive reworking of the system and refilling, which is often not economically feasible.
The device in refrigerators with a drip system
The situation with classic “crying” refrigerators Bosch is radically different. Here the evaporator is often integrated directly into the structure of the rear wall of the refrigerator compartment or is a coil foamed in thermal insulation. Visually, you can see only part of it - the so-called “plate”.
In the freezer compartment of such models (if it is not No Frost), the evaporator can be made in the form of an open coil, which is overgrown with frost. This is a normal phenomenon that requires periodic manual defrosting. The hidden evaporator in the refrigerator compartment cannot be found and “touched” without destroying the housing.
Diagnostics in such cases is based on indirect signs: the temperature of the tubes at the outlet of the compressor, the operation of the thermostat and the absence of characteristic gurgling. If the back wall in the refrigerator compartment is not evenly covered with condensation, there may be a problem with the refrigerant distribution or a leak.
⚠️ Attention: Attempting to open the foam housing to look for a leak in the hidden evaporator often leads to permanent damage to the insulation. In such cases, craftsmen often install an external cooling circuit However, understanding that the tube is “hidden in the wall” helps to avoid futile attempts to find the hole from the outside. Repairing such systems requires a professional approach and vacuuming. along the perimeter of the door.
However, understanding that the tube is "hidden in the wall" helps avoid futile attempts to find the hole from the outside. Repairing such systems requires a professional approach and vacuuming.
Access to the evaporator: step-by-step instructions
If you are determined to diagnose or replace a unit in the model No Frost, you will need a set of tools. First of all, this is a Phillips screwdriver, a spatula for carefully snapping off the clips and a container for water, since the ice will still have to be melted.
Start by completely disconnecting the device from the network. This is critical as you will have to work with the fan and sensor wiring. Next, remove all products and removable elements of the chamber.
☑️ Preparation for disassembly
The defrosting stage follows. Leave the doors open for at least 12 hours. Using a hair dryer is acceptable, but only at a minimum temperature and without direct contact with plastic parts, so as not to deform them.
After removing the ice, unscrew the visible screws on the back panel. Often the fasteners are hidden under decorative plugs or located inside a niche where products are usually stored. Carefully pull the panel towards you, trying not to damage the wires going to the fan.
| Work stage | Required tools | Completion time | Difficulty |
|---|---|---|---|
| Defrosting the chamber | Towels, basin | 12-24 hours | Low |
| Removing panels | Screwdriver, spatula | 15-30 min | Medium |
| Dismantling the heating element | Multimeter, pliers | 20-40 min | High |
| Evaporator replacement | Refrigerator kit | 2-4 hours | Pro |
When the panel is removed, you will see the evaporator itself. It may look like a dense bundle of aluminum plates with copper or aluminum tubes running through them. It is on these tubes that defrost heating elements are often mounted. temperature sensors and defrosting heating elements.
Diagnostics of heat exchanger faults
The most common problem faced by owners Bosch —this is the freezing of the evaporator “into a monolith.” If the fan hums, but does not spin, or spins, but does not blow cold, it means that the ice coat has completely blocked the channels.
The reason may be not only the failure of the defrost heating element, but also a malfunction defrost sensor, which does not give the command to heat, or the timer/control module. The drainage hole is also often clogged, and the water has nowhere to drain.
- 🧊 Ice blocks the fan blades - a cracking or humming sound is heard.
- 💧 Water flows inside the chamber or under the refrigerator due to a blockage drainage.
- 🌡️ The compressor works without stopping, trying to gain temperature.
- 🔌 Ice freezing on only one side of the evaporator indicates a freon leak.
To check the heating element, you need to “ring” it with a multimeter. The resistance of a working heater is usually in the range from 200 to 400 Ohms (depending on the power of the specific model Bosch). If the device shows a break, the element requires replacement.
Replacement and maintenance of the unit
If diagnostics showed that the evaporator itself is damaged (for example, through corrosion or mechanical breakdown), it must be replaced. In the case of No Frost this means purchasing an original radiator or a high-quality analogue for your series.
The replacement process includes not only mechanical installation, but also soldering of pipes, evacuation of the system and charging with refrigerant. This is a job for a certified specialist licensed to work with freons.
However, maintenance, such as cleaning the drain hole or replacing the heating element, is quite within the capabilities of a careful home handyman. The main thing is not to forget to check the integrity of the wire insulation before turning it on.
⚠️ Attention: Technical characteristics of refrigerators Bosch may vary depending on the year of manufacture and region of assembly. Always check the markings on the label inside the chamber before ordering spare parts.
Regular maintenance, including defrosting at least once a year (even for No Frost) and cleaning the drainage, will significantly extend the life of your refrigerator. This will allow you to avoid costly repairs of the compressor due to operation in extreme conditions.
Is it possible to operate a Bosch refrigerator without a back panel in the freezer?
For a short time - yes, for example, for diagnostics. However, prolonged operation without the panel will disrupt the circulation of air flows calculated by the engineers. This will lead to incorrect operation thermostat, increased noise and moisture entering the open electrical contacts.
Why does the refrigerator not freeze after replacing the evaporator?
The most likely reason is poor-quality soldering or insufficient vacuuming the system. There may be air or moisture left in the circuit that is blocking refrigerant circulation. It is also possible that the amount of refilled freon does not correspond to the model's passport data.
How often do you need to defrost a No Frost refrigerator?
Technically, the No Frost system does not require defrosting. However, manufacturers Bosch recommend turning off the device at least once every 1-2 years for hygienic washing and checking the drainage system. This will help avoid the appearance of unpleasant odors and bacteria.
Where is the evaporator located in a two-chamber refrigerator with one compressor?
In such models evaporator almost always located in the freezer (at the top or bottom, depending on the design). Cold is supplied to the upper refrigerator compartment through an air duct using a damper and a fan. There is no separate evaporator in the refrigerator compartment.