Sudden stoppage of the compressor or a characteristic click followed by a hum, but the engine does not start - these are classic signs of failure of the starting mechanism. For owners of Soviet-made equipment, such as refrigerator Pole, repairs often come down to replacing this particular unit. Understanding where the relay is located and how it works is the first step to restoring the unit's functionality without calling a repairman.
This component is responsible for supplying a starting pulse to the electric motor windings, after which it turns off, transferring the work to the main winding. In models Polyus refrigerators, which were often equipped with compressors of the B, K series or later modifications, the relay is usually mounted directly on the motor housing. However, the exact location and method of fastening may vary depending on the year of manufacture and the specific modification of the compressor unit.
Before proceeding with disassembly, it is important to make sure that the problem lies in the starting device, and not in the engine or thermostat itself. In old Polus models, RTP-1 or RTK relays were often used, which have a characteristic black or gray rectangular plastic case. Independent diagnostics require caution, since work will have to be done with electrical components under high voltage.
Design and principle of operation of the starting device
To effectively troubleshoot a fault, it is necessary understand the internal workings of the trigger mechanism. In Pole refrigerators electromagnetic current relays were most often used, although thermal protection could also be found in later modifications. The main task of the element is to briefly connect the starting winding of the engine at the moment of start.
The principle of operation is based on the passage of current through the relay coil. When the compressor starts, the current is high, the magnetic field draws in the core and closes the contacts of the starting winding. As soon as the engine picks up speed, the current drops, the core, under the influence of gravity or a spring, returns to its original position, opening the circuit. If this process is disrupted, the motor hums, but does not spin.
- 🔌 Contact group —moving and stationary contacts, which often burn out when turned on frequently.
- 🧲 Electromagnetic coil —creates a field for closing contacts, may burn out or lose properties.
- 🛡️ Thermal protection - a bimetallic plate, often combined with a relay, turns off the motor when overheated.
It is important to note that in the design of the Polyus refrigerator the relay often combined with a thermal protection relay. This is a single block that fits onto the three terminals of the compressor. Malfunction of any of the elements of this unit requires its complete replacement, since repairing internal components at home is impractical and unsafe.
The exact location of the relay in the unit
Searching for a relay in Polyus refrigerator does not require dismantling the entire housing. Access to the unit is through the lower part of the rear wall of the unit. The compressor unit is located in a niche, which is usually covered with a metal or plastic panel. This is where the part you are looking for is located.
After removing the protective cover of the compressor (if there is one), you will see a black cylindrical or pear-shaped motor. On its side, in the lower part, there is a small plastic box attached - this is the starting relay. It is placed directly on the compressor rod and secured with a bracket or screw.
⚠️ Attention: Before removing protective panels and touching any electrical parts, be sure to disconnect refrigerator Polyus from the electrical outlet. Residual voltage or accidental switching on can lead to serious injury.
In some modifications, especially if a previous replacement was carried out, the relay can be output to a separate wire or mounted next to the frame, but this is rare for the standard configuration. Poles. The standard location is the “tail” of the compressor. To access, you may need to move the refrigerator away from the wall and remove the back panel if it blocks access to the bottom.
Diagnostics of faults in the starting relay
You can determine that it is the relay that has failed, and not the compressor itself, by characteristic signs. If Polyus refrigerator turns on, there is a click, the motor hums for a few seconds, and then another click and silence - this is a sure sign of a problem in the starting circuit. Often, thermal protection is triggered.
Visual inspection can also give results. The removed relay should not have any traces of burning, melted plastic or the characteristic smell of burnt insulation. If carbon deposits are visible on the contacts inside the housing or the core is damaged, the part requires replacement. It is also worth checking the integrity of the wires going to the terminals.
For more accurate diagnostics, you can use a multimeter. The resistance between the contacts must be within the normal range (usually a few ohms for the coil). If the device shows an open or short circuit, the relay is faulty. In the case of Pole refrigerators contacts sticking or loss of elasticity of the core return spring often occurs.
How to check the relay without instruments?
Shake the relay near your ear. If a knock is heard inside (as from a broken stone), it means that the internal tablet (for posistors) or the core is destroyed. For electromagnetic relays this is less informative, but core play is also undesirable.
Instructions for removing and installing the part
The process of replacing a relay in refrigerator Polyus is technically simple, but requires care. The main thing is not to damage the compressor tubes and connect the wires correctly. First, remove the back panel and gain access to the motor.
Carefully remove the retaining bracket or unscrew the screw holding the relay housing. Then, by gently rocking from side to side (without jerking up and down, so as not to break the compressor tubes), remove the relay from the rod. Pay attention to the wiring diagram: it is better to photograph them before disconnecting.
☑️ Algorithm for replacing the relay
Installing the new relay is done in the reverse order. It is important that the contacts sit tightly on the compressor terminals. If you change the type of relay (for example, install a universal one instead of a native RTP), you may need to adapt the seat or use adapters, since the geometry of the leads may differ from one manufacturer to another.
⚠️ Attention: Never leave the wires simply twisted or on insulating tape in the high temperature zone of the compressor. Use standard terminals or high-quality heat shrink to avoid short circuits.
Compatibility table and relay types
When selecting spare parts for of the Polyus refrigerator it is important to take into account the power of the compressor and the type of refrigerant, although in older models it is most often freon R12. An incorrectly selected relay will either lead to frequent shutdowns or burnout of the motor windings.
Below is a table of the main types of relays that were found in various technologies, including analogues for Poles. Refer to the markings indicated on the body of your part.
| Relay type | Marking | Application | Features |
|---|---|---|---|
| Electromagnetic | RTP-1, RTK-1 | Compressors B, K (old Poles) | Works in any position, sensitive to vibration |
| Thermal (protection) | RT-1, RT-2 | Together with the starting one | Responses to current and temperature, often in one housing |
| Posistor | PR-0.1 (analog) | Modern replacements | Works only in a vertical position, no moving parts |
| Universal | 610618 (and analogues) | Replacement of failed ones | Requires selection according to compressor power (HP) |
When choosing an analogue, pay attention to the power in horsepower (HP). For Pole refrigerators relays with a power of 1/8 or 1/6 HP are usually suitable. Installing a more powerful relay may lead to the fact that it will not open the circuit, and the starting winding will burn out.
Common mistakes during self-repair
One of the common mistakes is ignoring the condition of the compressor itself. If Polyus refrigerator worked for a long time with a faulty relay, the engine could overheat. In this case, even replacing the relay will not start the unit, since the internal protection has tripped or an interturn short circuit has occurred.
Another mistake is installing a relay of the wrong type. For example, posistor relays will not work if they are installed sideways, since they require gravity to cool and open (in some designs) or simply a specific temperature regime. Electromagnetic ones must hang strictly vertically.
Also, users often forget to clean the contacts from oxides before installing a new part. Dirt and oxides on the compressor terminals can cause poor contact, which will lead to a voltage drop and incorrect operation of the new relay.
⚠️ Attention: Specifications of compressors and compatible relays may vary depending on the specific production batch. Always check the markings on the nameplate of your Polyus refrigerator with the data on the new part before purchasing.
Prevention and service life
The service life of the starting relay directly depends on operating conditions of the Polyus refrigerator. Frequent power surges, dust and dirt in the rear niche, as well as compressor overheating due to poor ventilation shorten the life of the part. Regular cleaning of the back wall and providing a gap near the wall will extend the service life.
If you notice that the refrigerator has begun to turn on more often than usual or the compressor has become noisier, this is a reason to carry out diagnostics. Timely replacement of an inexpensive relay can save an expensive compressor from burning out. In older models Polyus reliability of the starting system is a key factor in durability.
Remember that high-quality repair is not only about replacing a part, but also about understanding the cause of the breakdown. If the new relay burns out after a week, then the problem is deeper: perhaps the thermostat is faulty, which does not allow the compressor to rest, or there are problems with the electrical wiring of the unit itself.
FAQ: Frequently Asked Questions
Is it possible to start a Polyus refrigerator without a relay?
Theoretically, It is possible to apply voltage directly to the starting winding manually for a short time to start the motor, but this is extremely dangerous and is not recommended. Without a relay, the compressor will not be able to operate normally and will quickly burn out or trip the circuit breaker. Operation without a relay is impossible.
Where to buy a relay for an old Polyus refrigerator?
Original RTP-1 or RTK-1 relays are now difficult to find; they can be sold on radio markets or in spare parts stores for old equipment. However, there are modern universal analogues (for example, series 610618), which are suitable for electrical parameters and can be installed with minimal modification of the fastening.
Why is the compressor humming, but the refrigerator is not freezing?
If the compressor is humming, but does not start (a click is heard), then the start relay is most likely faulty or jammed compressor If the motor runs continuously, but there is no cold, the problem may be a freon leak, a clogged capillary tube or a malfunction of the thermostat, and not the relay.
How to distinguish an RTP relay from an RTK?
The RTP relay (starting) usually has a more compact housing and is responsible only for starting. RTK (thermal starting) is often larger in size, as it combines the functions of starting and thermal protection. There is always a marking on the case. For of the Polyus refrigerator it is important to select an analogue with the appropriate cut-off current.
Is it dangerous to change the relay yourself?
The main danger is electric shock when the device is plugged in. If you follow the rule: “If you unplug it, only then touch it,” the replacement process is safe. Mechanical damage to the copper tubes of the compressor due to careless removal of the relay can also lead to freon leakage, which will require expensive refilling.