The idea of converting a freezer into a full-fledged refrigerator compartment often arises among those who are faced with an excess of space for freezing and a lack of space for cooling products. Owners of old Soviet units or compact freezers like Morozko sometimes consider this option as a way to extend the life of the equipment or adapt it to new needs without purchasing new equipment. However, technically this process represents a complex engineering problem that requires a deep understanding of the principles of operation of the refrigeration cycle.
The main obstacle lies in the fundamental difference in operating temperatures and evaporator design. The freezer compartment is designed to maintain temperatures between minus 18 and minus 24 degrees Celsius, while the refrigerator compartment requires a stable temperature range of +2 to +8 degrees. Simply changing the thermostat settings will not help here, since heat exchange and the compressor power are designed for other load parameters. An attempt to simply “raise” the temperature can lead to improper operation of the defrosting system or overload of the engine.
Nevertheless, technically competent alteration is possible if you have the appropriate skills and tools. Not only will you need to replace the control electronics, but you may also need to tamper with the evaporator design or refrigerant circulation system. It is important to understand that any intervention in a sealed circuit requires a professional approach and compliance with safety precautions, since the refrigerant is under pressure.
⚠️ Attention: Independent violation of the seal of the refrigeration circuit without special equipment (vacuum pump, pressure gauge station) and skills in soldering copper pipes can lead to irreversible damage to the compressor and leakage of freon, which is also harmful to ecology.
Fundamental differences in the operation of cooling systems
To successfully modify the device, you must clearly understand the physical differences between the freezing and cooling modes. In the freezer, the evaporator, often an aluminum plate or coil on the back wall, is cooled to very low temperatures. Thermoregulator in such a system it is configured to open the circuit when it reaches, for example, minus 20 degrees. If you leave this thermostat, the chamber will turn off too rarely or not at all, trying to achieve unattainable cold in conditions of changed thermal insulation.
In the refrigerator compartment, the operating cycle is shorter and the temperature difference is less. The key element here is the accuracy of maintaining above-zero temperatures so that food does not freeze or spoil. When remodeling, the problem of condensation often arises: the walls, which were dry and covered with frost in the freezer, will begin to constantly “cry” in refrigerator mode. This requires organizing the correct drainage and, possibly, installing a fan for forced air circulation, if the design does not provide for this.
It is also worth considering the difference in thermal insulation. The walls of the freezer are usually thicker, which is good for maintaining cold, but has a bad effect on heat transfer if you plan to use a standard condenser (grid on the back), which may be designed for a lower heat load in terms of refrigerator mode. The freezer compressor is usually more powerful (high-speed), which in refrigerator mode can lead to frequent switching on and off, reducing the life of the start relay.
Necessary tools and components for modernization
To implement the project, you will need a specific set of tools and spare parts. You can't just "twist" the wires; replacement of key control units will be required. The main element will be a new thermostat designed for positive temperatures, for example, models of the series TAM or K59 with the corresponding response range. It may also be necessary to replace the start-protection relay if the standard one does not fit the new operating mode of the compressor.
The table below shows an approximate list of components that may be needed depending on the complexity of your upgrade:
| Component | Purpose | Necessity |
|---|---|---|
| Thermostat (Tam-133, K-59) | Temperature adjustment +2...+8°C | Required |
| Defrost heating element | De-icing (if there is no No Frost) | Optional |
| Defrost sensor | Evaporator temperature control | Depends on the circuit |
| Fan | Air circulation (for No Frost) | Recommended |
Among the tools, it is necessary to have a multimeter for checking circuits, a set of screwdrivers, pliers and, possibly, tools for working with refrigerant if rehanging the pipes is required. Don't forget to prepare sealant to insulate the thermostat capillary tube insertions to avoid cold loss. All electrical connections must be made using terminal blocks and heat-shrinkable tubing; twisting in this case is unacceptable due to vibration and humidity.
☑️ Preparation for modernization
Step-by-step instructions: replacing the thermostat
The safest and A common adaptation method is to replace the thermostat without interfering with the freon circuit. This method is suitable if the difference in evaporator temperature is not critical or if you are willing to put up with the fact that the compressor will operate in abnormal mode. First you need to remove the old thermostat. To do this, remove the temperature regulator, disconnect the terminals and carefully remove the sensitive tube from the seat.
The new thermostat should have similar geometric dimensions and the length of the capillary tube. If the tube is longer, it can be carefully rolled into a ring without bending or wringing, since there is gas or liquid inside that reacts to pressure. Installation is carried out in the reverse order: the tube is inserted into the standard hole, the case is fixed, the wires are connected according to the color markings or diagram on the case.
After assembly, it is necessary to carry out testing. Turn on the device and place the thermometer inside. Check the readings after a few hours. If the temperature drops below zero and food begins to freeze, additional calibration may be required with the screw on the thermostat housing (if there is one) or the installation of additional resistance in the circuit, which requires knowledge of electronics. In some cases, installing a thermostat with a narrower operating temperature range helps.
⚠️ Attention: Never shorten the thermostat capillary tube! This will disrupt the calibration of the device, and it will not work correctly, which can lead to defrosting of food or freezing of the chamber.
Working with the No Frost system and air circulation
If you are upgrading a modern chamber with the system No Frost, the task is complicated by the presence of a fan and air supply channels. In freezer mode, the fan runs continuously or in cycles to quickly dissipate heat. In refrigerator mode, an intense flow of cold air can dry out food (vegetables and fruits will wither within a day). Therefore, it often becomes necessary to turn off the fan or change the algorithm of its operation.
To do this, you can install a separate switch or program the controller (if the model allows) for intermittent operation. It is also important to check the condition of the defrost heating element. In refrigeration mode, ice formation occurs more slowly, but the drain hole may become clogged more often due to changes in the nature of the condensation. It is recommended to clean the drainage channel and check the water collection pan under the compressor.
Pay special attention to the door seal. When the temperature changes, rubber can behave differently: become harder or, conversely, too soft. Check the fit around the entire perimeter. If the door does not fit tightly, warm air will constantly flow inside, forcing the compressor to work without stopping, which will ultimately lead to its combustion.
What will happen if you do not turn off the fan?
When the fan is constantly operating in refrigerator mode (+5°C), the products located directly in front of the air flow may become covered with a crust of ice or dry out, despite the positive temperature in the chamber.
Energy efficiency and operating risks
It is important to realize that a converted device will not have the same energy efficiency as a factory refrigerator. A compressor designed for deep cold may consume more energy in gentle cooling mode due to non-optimal switching cycles. In addition, the engine life in an unusual mode may be reduced. Constant monitoring of the current consumption and temperature of the compressor housing in the first weeks of operation is mandatory.
There is a risk of the formation of a “snow coat” on the products if the humidity is not regulated. Unlike dedicated refrigerators, a converted freezer may not have a freshness zone or controlled humidity. This makes storing vegetables and fruits problematic. Meat and dairy products will feel fine, but greens will quickly lose their presentation.
Another aspect is noise. Freezing compressors are often louder than refrigeration compressors. If the device is planned to be installed in the kitchen or living room, this can become an irritating factor. Vibrations can also be transmitted to the housing more strongly, requiring additional installation of the device on anti-vibration pads.
Alternative solutions and conclusions
Before proceeding with complex technical rework, it is worth considering alternative options. For example, using the freezer exclusively for storing frozen food, but at a higher temperature (for example, minus 6... minus 10 degrees), if the thermostat allows such adjustment. This is the “quick freezing” mode or storage of semi-finished products that do not require deep freezing. This is safer for equipment.
If you critically need a refrigerator, but there is no way to buy a new one, sometimes it is easier to find a used refrigeration compartment from a similar model and replace the insides, preserving the body. But this requires matching dimensions and fastenings. In most cases, the economic viability of a remodel is questionable, unless you are doing it for sport or a unique design project.
To summarize, turning a freezer into a refrigerator is a task for enthusiasts with refrigeration skills. For the average user, it is safer and more reliable to use the equipment for its intended purpose or purchase a specialized unit. However, if you decide to experiment, strictly follow the instructions, observe safety precautions and be prepared for the fact that the result may differ from what was expected.
Is it possible to simply set the temperature to -1 degree on the thermostat?
Most household thermostats for freezers do not have a scale with positive values or zero. Their range usually starts from minus 14 or minus 18 degrees. It is possible to mechanically limit the stroke of the rod, but this does not guarantee accuracy and stability of temperature in the positive range.
Will the compressor burn out if you use the freezer as a refrigerator?
The risk is great. The compressor may operate in short cycles (on and off frequently), which is harmful to the starting winding and relay. It is also possible for the oil to be underheated, since in order for the oil to return to the crankcase, a certain boiling point of the refrigerant is needed, which may not be achieved in refrigerator mode.
Does freon need to be changed during modification?
No, the type of refrigerant (freon) does not depend on the temperature in the chamber, but depends on the design of the entire system. Freon needs to be changed only if there is a leak or a leak in the circuit, which requires professional intervention.
What temperature is considered safe for storing meat in a converted chamber?
For short-term storage (2-3 days) of meat and fish, a temperature from 0 to +4 degrees Celsius is considered safe. For dairy products and ready meals, the optimal range is +2...+6 degrees. Monitor the temperature with an external thermometer.