The situation when the refrigerator Atlant stops cooling, and the motor is silent or makes only short clicks, often confuses the owner. In most cases, the culprit is the starting relay, which protects the motor from overloads. However, in order not to buy a new part at random, it is necessary to exclude damage to the very heart of the unit - the compressor. Diagnosing the motor directly, bypassing the standard starting system, is the most reliable way to determine its performance.
Such a test requires strict adherence to safety precautions, since you will be dealing with a mains voltage of 220 volts and open contacts. The purpose of this method is to determine whether electric motor has the ability to start and maintain operation, or whether its windings have burned out, or a mechanical wedge has occurred. If the motor starts from an external source, then the problem lies in the control electronics or relay.
In this article we will analyze in detail the algorithm of actions, the necessary tools and precautions. You will learn how to visually assess the condition of the unit, carry out initial diagnostics with a multimeter and perform a forced start. This will allow you to accurately diagnose the malfunction and make a decision to repair or replace the unit.
Preparation for diagnostics and safety measures
Before starting any work on electrical equipment, you must completely turn off the power to the refrigerator. Unplug the power cord and gain access to the rear of the unit. To work, you will need a set of tools: a screwdriver, pliers, a multimeter (tester) and, possibly, insulating tape. Don't neglect these basics, as safety is the number one priority.
Remove the protective cover of the compressor compartment, which is usually secured with bolts or latches. In models Atlant access to the motor is often open, but it may be necessary to remove the entire rear panel. Inspect the appearance of the compressor: there should be no traces of oil, severe corrosion or swelling. Any oil leaks may indicate depressurization of the system, which makes further diagnostics pointless without a technician.
⚠️ Attention: It is strictly forbidden to touch the exposed wires and contacts of the compressor while connecting to the network. The risk of electric shock is extremely high. Carry out all manipulations with the wires only when the power is turned off.
It is also important to check the condition of the wiring. The insulation of the wires going to the relay and compressor must be intact, without cracks or melting. If damaged areas are found, they must be isolated or replaced before testing. Using a working tool with intact probes is also a prerequisite.
☑️ Checklist for preparing for testing
Visual inspection and initial assessment of condition
Before climbing with instruments, carefully examine the compressor. On many models Atlant, especially older series, you can find signs of overheating. If the paint on the motor body has changed color (darkened) or there is a burning smell, this is a bad sign. Such symptoms often indicate an interturn short circuit or long-term operation in emergency mode.
Pay special attention to the tubes. The copper pipes leaving the compressor must be dry. The presence of oil around the fittings indicates that the freon has evaporated, and with it the compressor oil has flowed out. In this case, start the motor It is absolutely forbiddeneven for a short time, since it will burn out in seconds without lubrication and cooling.
Check the motor mounting. The compressor in refrigerators Atlant is suspended on springs inside the casing or mounted on legs. If the fastenings are loose, there will be strong vibration and noise during operation. Sometimes the cause of failure is not electrical, but mechanical jamming due to misalignment.
Diagnostics of windings with a multimeter
The very first and safest stage of testing is checking the continuity of the electric motor windings. To do this, you need to disconnect the start relay from the compressor contacts. Usually it is simply removed from the pins. At the end of the compressor you will see three contacts forming a triangle. These are the terminals of the starting and operating windings and the common wire.
Switch the multimeter to resistance measurement mode (Ohms). Measure the resistance between each pair of contacts in turn. Normal values for refrigerators vary, but the general picture should be as follows: the resistance between the working and common windings is approximately 10-30 Ohms, and between the starting and common windings it is slightly higher, about 20-40 Ohms. The total resistance between the starting and working windings should be equal to the sum of the two previous measurements. Atlant vary, but the general picture should be as follows: the resistance between the working and common windings is approximately 10-30 Ohms, and between the starting and common windings it is slightly higher, about 20-40 Ohms. The total resistance between the starting and working windings should be equal to the sum of the two previous measurements.
If the device shows one (infinity) in any section, it means in the winding break. If the resistance is close to zero, a short circuit has occurred. In both cases, the compressor is considered faulty and requires replacement. It is also important to check the breakdown on the housing: one probe is placed on any contact, the other on the part of the compressor housing that has been cleared of paint. The device should be silent.
Why is it important to check for breakdown?
A breakdown to the housing means that the phase is shorted to the metal casing. If such a compressor is turned on, the entire body of the refrigerator will be energized, which is fatal to a person if touched.
It is convenient to summarize the measurement results in a table for analysis:
| Pair of contacts | Normal resistance | Fault |
|---|---|---|
| Working - General | 10–30 Ohm | Open or short circuit |
| Starting - General | 20–40 Ohm | Open or Short circuit |
| Any contact - Housing | Infinity (∞) | Insulation breakdown |
Method of direct start of the compressor
If the electrical parameters of the windings are normal, proceed to the actual important stage - an attempt to start the engine without a standard relay. To do this you will need a piece of wire with a plug. Strip the ends of the wire. The connection diagram is simple: one wire from the plug (phase or zero, for asynchronous motors this is not critical at the first stage) is connected to the lower left contact (conditionally “common”), and the second wire is connected to the upper contact (working winding). We do not touch the third contact (starting) yet.
Plug the plug into the socket. If the compressor is working properly, it should hum, but will not start because there is not enough starting impulse. At this moment, you need to briefly touch the contact of the starting winding with the third wire (or jumper), the second end of which is already connected to the network. The motor should start and start working. As soon as it starts, the starting wire must be removed immediately, otherwise the winding will burn out.
⚠️ Attention: The contact time with the starting winding should not exceed 1-2 seconds. Holding it for a long time will lead to overheating and failure of the starting winding. Be prepared to quickly withdraw your hand.
Successful starting and a smooth hum of a running motor means that the problem itself is the compressor working?lies in the relay, thermostat or wiring. If the motor hums, twitches, but does not start even with a starting impulse, or immediately knocks out the machine, there is a mechanical wedge or a strong inter-turn short circuit.
Analysis of current consumption and pressure
For deeper diagnostics, professionals use current ticks. This device is placed on one of the power cables of a running compressor. Normal current consumption for household refrigerators Atlant is from 0.3 to 0.7 Amperes in operating mode. At the moment of startup, the current may briefly jump to 3-5 Amperes, but then it must fall.
If the current consumption is significantly higher than normal (for example, 1.5–2 A and growing), this is a sure sign of a heavy stroke of the piston group or an impending wedge. The motor is trying to work, but the mechanical resistance is too great. In this mode it will not last long and will burn out. Also, a high current may indicate a malfunction in the electrical part of the engine.
Another method available to technicians is checking the outlet pressure. A pressure gauge station is connected to the outlet fitting (supercharger). A working compressor should produce a pressure of at least 6 atmospheres (bar) and quickly gain 10-15 atmospheres. If the pressure gauge needle barely crawls or stands still, it means that the valves inside the compressor are worn out or broken, and it does not create the required compression.
Typical malfunctions and their symptoms
Understanding the symptoms helps to make a diagnosis faster. Let's consider the main scenarios that equipment owners face Atlant. Each of them has its own characteristic signs that make it possible to distinguish a compressor breakdown from problems with a relay or thermostat.
- 😶 Complete silence: The refrigerator is on, the light is on, but the motor is silent. Most likely, the start relay has burned out, the thermostat is faulty, or there has been a break in the power circuit. The compressor itself may be intact.
- 🔊 Humming and clicking: The motor tries to start, hums for 5-10 seconds, then a click is heard (the thermal relay is activated) and silence. This is a classic symptom of a compressor wedge or failure of the starting winding/relay.
- 🔥 Strong heating: The compressor works, but the housing becomes hot to the point where it is impossible to touch it with your hand. This may be a sign of a freon leak (the motor is not cooled by the returning gas) or an interturn short circuit.
- 💨 It works, but does not cool: The motor rotates smoothly, the current is normal, but it is warm in the chamber. Here the problem is not in the electrics of the compressor, but in its mechanical part (no compression) or in a refrigerant leak from the system.
It is important to note that the symptoms may overlap. For example, if there is a freon leak, the compressor will work almost without interruption, trying to gain temperature. This leads to its overheating and eventual breakdown. Therefore, diagnostics must be comprehensive.
What is a thermal release?
This is protection built into the relay or on the compressor housing. It opens the circuit if the case temperature or current exceeds the norm, preventing a fire. If it works frequently, look for the cause of the overload.
Frequently asked questions (FAQ)
Is it possible to restore a jammed Atlant compressor?
There is a method of "un wedging" by applying high voltage or shaking, but at home it is dangerous and rarely gives a long-lasting result. If the compressor is mechanically jammed, it is easier to replace it with a new or used analogue.
Which compressor is better to replace the old one?
For refrigerators Atlant original compressors from the same manufacturer are ideal. They have identical mounting dimensions and characteristics. Installing analogues from other brands (for example, Danfoss or Embraco) is possible, but will require selection in terms of power and dimensions.
Why does the refrigerator not freeze after replacing the compressor?
The reason may be poor-quality sealing of the tubes, the presence of moisture in the system, or incorrect refilling of freon. The new motor could also burn out due to an unreplaced filter-drier or old oil residues in the system.
How much does it cost to have a compressor diagnosed by a specialist?
The cost of on-site diagnostics varies depending on the region and service center. Usually it is a small amount, which is often deducted from the cost of further repairs if you agree to it.
Is it dangerous to change the compressor yourself?
Yes, it is dangerous. In addition to the risk of electric shock, working with refrigerant requires special equipment (vacuum pump, pressure gauges) and soldering skills. Incorrect replacement will lead to damage to the new compressor and air pollution.