Converting an ordinary refrigerator into a full-fledged freezer is a task that only those who are ready for serious technical interventions can do. A standard household appliance is designed to maintain a temperature of around +4...+5°C in the main compartment, while deep freezing requires a stable temperature of -18°C or lower. Simply adjusting the thermostat knob will not help here, since the standard compressor and refrigerant will not be able to provide such a temperature difference without the risk of overheating and failure.
There are two main ways to solve this problem: using Low Ambient Kit (a kit for working in cold climates) or completely replacing the compressor with a more powerful unit. The first option is suitable if you just need to increase cooling, the second - if you need a full-fledged freezer. It is important to understand that any intervention in refrigeration circuit requires special equipment and skills in working with freon.
Before you begin, weigh all the risks. After modernization, energy consumption will increase by 1.5–2 times, and the service life of standard evaporator tubes may not withstand long-term operation in extreme conditions. However, if you want to get from an old one Indesit or Atlant a powerful chamber for storing meat and berries, this project has the right to life.
Analysis of the standard system and choice of compressor
The first step is to assess the capabilities of the existing unit. Standard compressors in refrigerators such as Donbass or Biryusa often have low performance. The freezer requires a unit that can maintain high condensation pressure at low evaporation temperatures. If you leave the old motor, it will run non-stop, which will lead to rapid burnout of the windings.
When choosing a new compressor, pay attention to its cooling capacity, indicated in watts or BTU. For a volume of 100–150 liters, a unit with a power of at least 200–250 W is usually required. It is also important to consider the type of refrigerant: switching from R12 to R134a or R600a requires a complete flushing of the system and an oil change, since different types of oils are not compatible.
- 🔧 Power: choose a compressor with a power reserve of 20–30% of the design load.
- ❄️ Refrigerant type: make sure that the new unit is compatible with the current one or get ready for a complete replacement of the circuit.
- 🔌 Starting device: check that the starting relay matches the motor type (RSIR, RSCR, CSIR).
⚠️ Attention: Using a compressor from a car air conditioner or industrial refrigeration equipment in a household building is unacceptable without serious modification of the electrical circuit and control system.
Replacing the thermostat and sensors
The standard refrigerator thermostat is set to turn off the compressor when it reaches +4°C. For a freezer, this threshold needs to be shifted to minus. Simply tightening the adjustment screw often does not give the desired range, so it is recommended to replace the entire assembly with an analogue from the freezer, for example Tam-133 or K-59 with the appropriate marking.
In systems No Frost the situation is more complicated, since they use electronic resistance sensors. Their readings are monitored by the main control module. To “deceive” the system, some technicians replace the sensors with analogues with other ratings, but it is safer to reflash the board or install an external thermostat that will break the compressor power circuit when the desired temperature is reached.
Installing a new thermostat requires precise calibration. The capillary tube of the sensor must be secured in the evaporator area, ensuring tight contact. If the contact is weak, the on-off cycle will be disrupted, and the temperature in the chamber will “walk” over a wide range, which is detrimental to the products.
☑️ Checking the thermostat
Modernization of the defrost and ventilation system
When deep When frozen, moisture from the food actively settles on the evaporator, turning into an ice coat. In a regular refrigerator this leads to periodic defrosting, but in freezer mode the ice builds up faster. If you have a model with a drip system, you will have to manually control the frost layer or implement an automatic defrosting system.
For models No Frost it is important to check the operation of the defrost heating element and timer. When the evaporator operates in an intensive mode, the standard heating element may not be enough to completely defrost the drainage system. In such cases, an additional heating element is installed or the operating time of the standard heating element is increased by reconfiguring the controller.
Air circulation also plays a key role. The air in the freezer must be constantly mixed so that the temperature is the same on all shelves. Check the serviceability of the evaporator blower fan. If it works poorly, in the far corners of the chamber the temperature will be significantly higher than that of the sensor.
| Component | Function | Risk in case of failure | Required action |
|---|---|---|---|
| Heating element defrosting | Heating of the evaporator | Icing of the channel | Replacement with a powerful one |
| Fan | Air circulation | Uneven cold | Lubrication or replacement |
| Defrost sensor | Temperature control | Failure to turn on the heating element | Calibration |
| Drainage | Water removal | Leakage inside | Steam cleaning |
Improving the thermal insulation of the chamber
Standard refrigerator insulation 3–4 cm thick may not be sufficient for long-term storage of food at -24°C, especially if the appliance is located in a warm room. Heat loss will cause the compressor to operate continuously. You can strengthen the insulation without completely disassembling the case.
An effective method is to paste the internal walls (if volume allows) or the outer rear wall with foil Penofol. It is important to use food grade material if insulation is placed inside. The joints of the sheets must be glued with aluminum tape to create a sealed heat-reflecting contour.
Pay special attention to the door seal. At low temperatures, the rubber becomes tanned and may no longer fit tightly. Lubricate the seal with silicone grease for elasticity or replace it with a more frost-resistant analogue from a model with a climate class. SN-T.
Can polyurethane foam be used?
Foaming the space between the walls is possible, but risky. When expanding, the foam can deform the internal plastic box or squeeze out the outer casing, violating the geometry of the door.
Electrical circuit and motor protection
Since the upgraded refrigerator will operate in intensive mode, standard protection may be insufficient. Be sure to install a voltage control relay that will protect the compressor from surges in the network. It is also useful to add a start-up relay with a wider range of operating currents.
Wiring inside the device should be checked for insulation melting. When working for a long time under load, old wires can get hot. It is recommended to replace the cables suitable for the compressor with copper cables with a cross-section of at least 1.5 mm².
To monitor the operation of the system, you can install an indicator lamp outside, which will light up when the compressor is operating. This will allow you to visually monitor the switching cycles and notice in time if the device stops turning off.
- ⚡ Voltage relay: a mandatory element for protecting expensive equipment.
- 🔥 Thermal protection: make sure that it fits snugly to the motor housing.
- 🔌 Grounding: when working in a humid environment, grounding the case is critically important.
⚠️ Attention: Carry out all work on the electrical part only with the device completely disconnected from the network. Residual voltage in capacitors can be dangerous.
First start-up and testing of modes
After assembling all components and filling with freon (if carried out) The testing stage begins. Don't load products right away. Let the camera go to idle mode. This will take from 3 to 6 hours depending on the volume and power of the compressor.
Use an external thermometer to monitor the temperature at different points in the chamber. The difference between the readings of the standard sensor and reality should not exceed 2–3°C. If the temperature “floats”, adjust the position of the thermostat capillary or electronic settings.
Listen to the operation of the unit. The hum should be smooth, without hydraulic shocks or whistles. If the compressor heats up above 70–80°C, it means it was selected incorrectly or there are problems with refrigerant circulation in the system.
⚠️ Attention: The characteristics of refrigerants and equipment safety requirements may change. Before purchasing freon and oil, check the current technical data sheets for compressor equipment and environmental standards in your region.
☑️ Final test
Frequently asked questions (FAQ)
Is it possible to make a freezer without replacing the compressor?
Theoretically, you can lower the temperature 5-7 degrees below standard by replacing the thermostat and improving the insulation. But it is extremely difficult to get a stable -18°C on an old motor - it will quickly fail due to overheating.
Which freon is best to use for the conversion?
It is better to use the type for which the evaporator and condenser are designed. Most often this is R134a. Switching to other types requires changing the oil and thoroughly flushing the system, which is difficult to do at home.
How much electricity will such a freezer consume?
Consumption will increase in proportion to the operating time of the compressor. If a regular refrigerator works 30% of the time, then a freezer can work 70-80%. Expect an increase in electricity bills by 2–2.5 times.
Do you need to change the oil in the compressor when remodeling?
If you do not open the circuit and do not change the type of refrigerant, there is no need to change the oil. If freon is replaced from mineral to synthetic (or vice versa), a complete oil change is required.