Sudden stoppage of the refrigerator Biryusa often becomes an unpleasant surprise, especially when food in the chamber begins to spoil. In most cases, the cause of the breakdown is the failure of starting relay a small but critical element of the electrical circuit. It is this unit that is responsible for starting the compressor engine and its further operation in normal mode.
Independently replacing or connecting a relay is a task quite feasible for a home craftsman with a minimum set of tools and basic knowledge of electrical engineering. However, it is important to understand that refrigerant circulates inside the refrigeration unit, and the system is under pressure, so any manipulations must be carried out strictly in compliance with safety precautions and only regarding electrical components.
In this article we will analyze in detail the design of the trigger mechanism, methods for diagnosing faults and a step-by-step algorithm for replacing the part. You will learn how to choose the right analogue if the original spare part is not on sale, and what nuances should be taken into account when assembling the compressor assembly.
The principle of operation and the design of the starting relay
The starting relay in refrigerators Biryusa performs the function of an automatic switch. When the refrigerator is turned on, voltage is supplied to the motor windings, but the rotor needs a powerful impulse to start. The relay closes the circuit of the starting winding, creating the necessary shearing torque, and after the engine accelerates, it opens the contacts, leaving only the working winding active.
There are two main types of devices that can be installed in various models of equipment. Induction relays work due to electromagnetic coils, which at a certain current draws in the core and closes the contacts. Thermal relays use a bimetallic plate that is heated by current and bends, opening or closing the circuit depending on the temperature.
⚠️ Attention: Inside the relay housing there is often a sensitive element, which can be made based on mercury or special alloys. Do not shake the part too much and do not open the case if you plan to reuse it.
Modern models are most often equipped with combined devices, where both starting and thermal protection elements are contained in one case. This simplifies the design, but requires a careful approach when diagnosing, since the failure of one element often entails replacing the entire unit.
Why does the relay burn out?
A frequent cause of contact burnout is low voltage in the network or frequent power surges. Also, a jamming of the compressor can lead to a breakdown when the engine tries to start, but cannot turn the shaft, consuming a huge current that melts the relay contacts.
Diagnostics of faults before replacement
Before buying a new part, you need to make sure that the problem lies in the relay, and not in the compressor itself or wiring. The first sign of a malfunction is a characteristic click, repeated every few seconds, while the refrigerator does not start and does not hum with the usual operating sound.
For accurate diagnosis, you will need a multimeter. After disconnecting the unit from the network and removing the rear protective panel, you need to remove the relay from its seat on the compressor. A visual inspection may reveal melted plastic, blackened contacts or the presence of carbon deposits, which is a direct indication of the need for replacement.
Checking the continuity of the circuit is carried out by testing the contacts. If, when rocking the relay, a knocking sound of the internal element is heard (in induction models), this is normal, but if the contacts do not ring in the desired position or, on the contrary, are short-circuited, the part is faulty.
- 🔍 Check for mechanical damage on the body and contact group.
- ⚡ Ring the windings with a multimeter in measurement mode resistance.
- 👂 Listen to the sounds inside the relay when shaking lightly.
It is also important to inspect the wires going to the relay. If the insulation is melted or the wires are oxidized, simply replacing the relay will not give a long-term result - it is necessary to restore the integrity of the wiring.
Preparation of tools and selection of spare parts
For successful repairs, you will need a minimum set of tools. The main working tool will be a screwdriver (usually a Phillips or flathead screwdriver, depending on the casing fastener) and pliers for removing terminals. A multimeter is required to check the circuit after installing a new part.
Selecting the right relay is a key step. The body of the old part always has markings, for example, RTK-X, R-3 or imported analogues Danfoss, Indesit. For refrigerators Biryusa domestic relays of the RTK series or their modern analogues are often used.
⚠️ Attention: Relays from different manufacturers may have different contact arrangements and housing shapes. Make sure that the geometric dimensions and contact pattern of the new relay match the original.
If you cannot find an exact analogue, you can use a universal relay, but in this case you will need to alter the fastening elements or use adapters, which does not always guarantee reliable operation.
Step-by-step instructions for replacing the relay
The replacement process begins with completely de-energizing the refrigerator. Unplug the power cord and move the unit away from the wall to allow easy access to the rear. Allow the compressor to cool for 15-20 minutes if it tried to work before.
Remove the cardboard or plastic cover covering the compressor compartment. You will see a black cylindrical compressor tank, at the end of which the desired device is attached. Carefully remove the retaining bracket or bar that holds the relay in place.
☑️ Algorithm for replacing the relay
Remove the old relay, by pulling it down or to the side (depending on model). Inspect the contact group on the compressor - it should be clean, without traces of burning. If the contacts are oxidized, carefully clean them with fine sandpaper.
Install the new relay by sliding it onto the contact pins of the compressor. It is important to maintain the correct orientation: usually there is a marking UP or arrow on the housing indicating the top position. Incorrect installation can lead to immediate failure of the new part.
Connect the wires to the relay contacts according to the previously made diagram or photograph. Make sure the connections are tight and not loose. Secure the relay with the retaining strip and install the protective cover in place.
Connection diagrams and contact markings
Understanding the connection diagram is necessary if the wires have been disconnected or mixed up. An electrical diagram is often printed on the relay body, where the contacts are designated by numbers or letters. Standard marking includes contacts for the working and starting windings, as well as a power input.
For single-phase motors used in Biryusa, the following scheme is typical: the common wire (Common) is connected to one terminal, the working winding wire (Run) to another, and the starting winding (Start) to the third through the trigger mechanism. An error in the connection will result in the motor humming without starting or a short circuit.
| Designation | Function | Wire color (typical) | Note |
|---|---|---|---|
C or 1 |
Common contact | Black or White | Connects to the network |
R or 2 |
Working winding (Run) | Red or Green | Constantly energized |
S or 3 |
Start winding (Start) | Blue or Yellow | Activated only at start |
Ground |
Grounding | Yellow-green | Connected to the case |
If on your relay markings are erased or different, use the technical documentation for the specific compressor model. Do not connect the wires at random - this is guaranteed to burn the motor windings or the new relay.
Checking operation after installation
After assembling all the elements, you can conduct an initial test. Plug in the refrigerator. In the first seconds, you can hear the characteristic click of the relay, followed by the smooth hum of the operating compressor. This means that the starting phase was successful.
Pay attention to the current strength if you have a current clamp. The current must not exceed the rated values indicated on the compressor nameplate. If the engine hums but does not start, and after a few seconds the click is heard again, it means that the relay is not performing its function or the compressor is jammed.
Let the refrigerator operate for about 30-40 minutes without loading food. Check if the relay itself gets hot. Light heating is acceptable, but if the housing becomes scalding hot or the smell of burning insulation appears, turn off the device immediately.
- ✅ The compressor started the first time and runs smoothly.
- 🌡️ The temperature in the chamber began to decrease after 20-30 minutes.
- 🔇 There are no extraneous knocks or vibrations in the compressor area.
If the start-up is successful, you can start loading products, but the full refrigeration cycle will only be established after a few hours of operation.
What to do if the compressor hums, but does not start?
If after replacing the relay the situation has not changed, perhaps the problem is in the compressor itself (an interturn short circuit or a mechanical wedge). It is also worth checking the capacitor if it is provided for in the circuit of your model.
Common mistakes and precautions
When repairing refrigerators on their own Biryusa masters often make typical mistakes that can lead to repeated breakdowns. The most common of them is ignoring contact cleaning. Installing a new relay on oxidized or burnt compress contacts will negate all efforts.
Another mistake is using a relay with inappropriate characteristics. Even if the part physically falls into place, its current characteristics may not correspond to the engine power, which will lead to frequent shutdowns or overheating.
⚠️ Attention: Never carry out repair work while the refrigerator is plugged in. Electrical shock, combined with the metal casing and possible moisture, can be fatal.
Also, the relay should not be left unprotected. The plastic casing and metal strip serve not only for fixation, but also for heat removal and protection from splashes during defrosting. Operation without a cover reduces the service life of the part.
If you are not confident in your abilities or diagnostics have shown complex electrical problems, it is better to contact a specialized service. Repairing a compressor group requires qualifications, and incorrect actions may lead to the need to replace the entire unit.
Is it possible to install a relay from another refrigerator model?
Theoretically, it is possible if the electrical characteristics (cut-off current, voltage) and geometric dimensions match. However, manufacturers use different connection schemes. Before installing the “donor”, be sure to check the contact diagram and make sure that the type of relay (inductive, thermal, posistor) is suitable for your compressor.
Why does a new relay burn out immediately after installation?
Most often this indicates a malfunction of the compressor itself. If there is an interturn short circuit in the motor windings, the starting currents can be abnormally high, which leads to instantaneous burnout of the relay contacts. Also, the cause may be a short circuit in the wiring or incorrect connection of the wires.
How often do you need to change the starting relay?
The relay does not have a strict expiration date. With a stable voltage in the network and a working compressor, it can last 10-15 years or more. Frequent replacements are only required if the quality of electricity is poor or there are hidden defects in the refrigerator motor.
Is it dangerous to change the relay in the Biryusa refrigerator yourself?
Replacing a relay is an electromechanical work and does not affect the sealed circuit with freon, and therefore does not require a license. The main danger is electric shock. If safety rules are strictly observed (de-energization, dry hands, insulated tools), the procedure is safe.