Owners of domestically produced refrigeration equipment are often faced with the need to intervene in the operation of the automatic defrosting system. Polyus refrigerators, especially models of older series, are equipped with open-type evaporators or systems close to drip, where periodic activation of heating elements is the normal operating mode. However, there are situations when the automation fails, or the user wants to forcibly stop the defrosting process for diagnostics or preservation of equipment.
Understanding exactly how it functions defrosting cycle in your model is critical to prevent food spoilage and compressor failure. In some cases, it is necessary to completely de-energize the heating element (heating element) so that it does not turn on spontaneously, causing overheating of the chamber or creating excessive humidity. It is important to know that in most Polus models with an open evaporator there is no full-fledged “No Frost” system, and “defrosting” often means the operation of a thermostat or timer defrost.
Further actions require caution, since you will be dealing with live electrical components. Before starting any work, you must completely disconnect the unit from the power supply by unplugging the plug from the socket. Ignoring electrical safety rules can lead to electric shock or damage to the control electronics.
⚠️ Attention: Forced shutdown of the defrost system on a working refrigerator will cause the evaporator to become coated with a “coat” of ice, which will reduce the cooling efficiency and may cause compressor failure.
Operation principle defrosting systems in Polyus refrigerators
To competently intervene in the operation of the unit, you need to understand the basic diagram. Classic models Pole often use an electromechanical timer or an electronic control unit, which switches the power circuit at certain intervals (usually every 8-12 hours of compressor operation). Instead of a compressor, it starts to work Evaporator heating element, which melts the ice on the walls of the chamber.
The process is controlled by temperature sensors. When the ice melts and the temperature rises to a certain value, the sensor opens the circuit and the refrigerator returns to cooling mode. If you choose to disable this process, you are effectively breaking the heater's power circuit or blocking the signal from the timer. In manually controlled models, everything is simpler - there is no automatic defrosting, and the user decides when to defrost.
Modern modifications may have more complex operating logic tied to a microprocessor. Here defrosting algorithm is registered in the controller memory. Intervention in the operation of such a system without specialized equipment is often limited to physically disconnecting the heating element from the terminal block.
Necessary tools and safety measures
Before you begin dismantling the panels and working with wiring, you should prepare a working tool. You will need a set of screwdrivers (Phillips and flathead), a multimeter to check the continuity of circuits, and possibly pliers. It would not be amiss to have a flashlight, since the interior of the refrigerator Pole is often poorly lit when the lamp is removed.
Safety is priority number one. Working with electrical appliances requires complete confidence that there is no voltage. Even if you are simply unplugging the wire, accidentally plugging the plug into the outlet at this point can be fatal. It is also worth remembering the fragility of the plastic elements of the case, which on older models may be dry.
- 🛠️ Tools: A set of screwdrivers, a multimeter, a knife (for carefully stripping contacts), electrical tape.
- 🧤 Protection: Dielectric gloves, dry shoes, no moisture on the floor.
- 🔌 Electrical: Complete disconnection from the network 15-20 minutes before starting work to discharge the capacitors.
⚠️ Attention: Do not use metal objects to pick out ice or plastic latches if there is voltage in the network - this can cause a short short circuit.
Physically disconnecting the evaporator heating element
The most radical and reliable way to stop defrosting is to physically break the power supply circuit of the heating element. This method is suitable for those cases when the heating element is faulty (for example, it penetrates the body or constantly heats) and needs to be excluded from the circuit before replacement. First you need to gain access to the back wall of the refrigerator or freezer, where the evaporator is located.
Remove the protective panel by unscrewing the mounting screws. Below this you will see the evaporator coil and the tube heater attached to it. The wires from the heating element go either directly to the timer or to the electronic module. Your task is to find the connection point and break the contact. Most often, the wires are connected through a terminal block or twist, closed with heat shrink.
After disconnecting the wires, their ends must be carefully insulated. Use quality tape or heat shrink tubing to prevent moisture from entering and causing short circuits. Leave the insulated ends freely accessible, but away from the moving parts of the fan (if there is one) and sharp metal edges.
☑️ Algorithm for turning off the heating element
Blocking the defrost timer
In models where it is used electromechanical timer, the process is controlled by a special shaft with cams, which rotates synchronously with the operation of the compressor. When it is time to defrost, the contacts inside the timer switch. To turn off defrosting without cutting the heating element wires, you can try to fix the timer in the “cooling” mode.
However, in practice this is difficult to do, since the timer mechanism continues to rotate. A more effective method is to turn off the control contact on the timer itself, which is responsible for supplying voltage to the defrost line. To do this, you will need an electrical circuit diagram of your model Pole, since the arrangement of contacts among different timer manufacturers (for example, Elin, Telco) may differ.
If you do not have the skills to read electrical circuits, it is better not to touch the timer, but limit yourself to turning off the heating element. Improper intervention in the operation of the timer can lead to the fact that the compressor will stop starting, and the refrigerator will simply stop cooling, although the light and fan will work.
What will happen if you leave a faulty heating element on?
If the heating element continues to heat due to sticking contacts of the timer or relay, the temperature in the chamber will begin to rise. This will lead to food melting, bacterial growth and possible melting of the plastic elements on the inside of the refrigerator. In the worst case, a fire hazard may arise.
Diagnostics of faults in the No Frost system
Often the desire to “turn off defrosting” arises among users who confuse the normal operation of the system with its breakdown. If the refrigerator hums, clicks, or you see steam from the ventilation during a compressor pause, this is normal operation of the system No Frost or drip system. You cannot turn off a working system.
Other signs indicate a malfunction: the refrigerator does not turn off, working around the clock; there is a thick layer of snow on the food in the freezer; The refrigerator compartment is too cold or, conversely, warm. In such cases, the problem lies in the defrost sensor, which “does not see” that the ice has already melted and continues to heat, or in the timer, which is “stuck” in the defrost mode.
For diagnostics, use a multimeter in dial mode. Check the resistance of the heating element - it should be in the range of 200-700 Ohms (the value depends on the power). If the device shows one (open) or zero (short circuit), the heater must be replaced. Also check the defrost temperature sensor: at room temperature, its resistance should change when heating or cooling.
| Component | Normal condition | Symptom of malfunction | Action |
|---|---|---|---|
| Evaporator heating element | Resistance 200-700 Ohm | Open or short circuit | Replacement |
| Defrost sensor | Resistance varies with temperature | Does not respond to heat/cold | Replacement |
| Timer | Clicks, switches modes | Stuck, no clicks | Replacement/Repair |
| Fuse | Rings when dialing | No contact | Replacement |
Manual defrosting as an alternative to repair
If automatic refrigerator Polyus has broken down, and there are no spare parts at hand, the only way out is to switch to completely manual control of the cooling cycles. This does not mean turning off the power forever, but it does require your continued participation. You yourself become a “timer” for your unit.
In this mode, you turn on the refrigerator only when the temperature in the chambers rises above the permissible level, and turn it off when the food is frozen or cooled. Or, if the heating element is faulty (it heats constantly), you turn it off according to the scheme described above, but then you will have to defrost the unit manually every 1-2 weeks, completely disconnecting it from the network for 10-12 hours.
This operating mode is not recommended for long periods of time, as it leads to increased wear on the compressor due to frequent starts or, conversely, long downtimes oil in the system. This is a temporary measure until the necessary spare parts are purchased.
⚠️ Attention: When defrosting manually, never use a hair dryer, hot water or a knife to crush ice. Allow the ice to melt naturally with the doors open, substituting water containers.
FAQ: Frequently Asked Questions
Is it possible to completely remove the heating element and not install a new one?
Technically, you can leave the wires insulated, but then the refrigerator will lose the No Frost function (if it was) or will require manual defrosting. The evaporator will become overgrown with ice, blocking the air channels, and the refrigerator will stop freezing in 1-2 weeks.
Why does the Polus refrigerator not turn off after defrosting?
Most likely, the defrost sensor (thermostat) is faulty, which should signal the completion of the process. It is “stuck” in a closed state and continues to supply voltage to the heating element or prevents the compressor from starting. A timer failure is also possible.
How often should defrosting normally occur?
Depending on the model and load of the chambers, the defrost cycle in Polyus refrigerators starts approximately every 8-12 hours of compressor operation. This process usually lasts from 15 to 30 minutes.
Is it dangerous to drive a defrosted refrigerator?
If by “drive” we mean transportation: yes, it is dangerous. There may be oil left in the compressor, which, when transported horizontally, will flow into the refrigerant circuit. After delivery, such a refrigerator must stand vertically for at least 4-6 hours before turning it on.