The compressor is the “heart” of the refrigerator, on which its performance depends. If the unit stops freezing, makes strange sounds or does not turn on at all, the first thing you need to check is this particular unit. But how can you determine that the problem is in the compressor and not in the thermostat or electronics? In this article we will analyze 5 reliable diagnostic methods - from the simplest (hearing test) to professional (measuring winding resistance with a multimeter).
You will find out which signs of malfunction indicate a compressor breakdown, how to correctly connect the tester, what values resistance is considered normal for different models (Atlant, Indesit, Samsung, Liebherr), and what to do if the engine “hums” but does not start. We will also give checklist for a quick check without tools and tell you in which cases repairs are possible with your own hands, and when it is better to call a specialist.
All methods have been tested on real refrigerators and are suitable for most household models - like old Soviet ones (Biryusa, Minsk), and modern inverter (LG, Bosch). If you have never held a multimeter in your hands, don’t worry: the first two methods do not require any equipment!
1. Primary diagnostics without tools: what can be checked “by eye and ear”
Before disassembling the refrigerator or looking for a tester, inspect the unit and listen to its operation. Experienced craftsmen claim that 80% of compressor breakdowns can be identified at this stage.without resorting to complex measurements. Here's what to pay attention to:
- 🔊 Sound of operation. Normally, the compressor should produce a uniform hum without clicking, grinding or vibration. If you hear frequent clicks of the relay (every 5-10 seconds), this is a sign that the engine is trying to start, but cannot.
- ❄️ The temperature in the chambers. Touch the back wall of the refrigerator: if it room temperatureis not cool, the compressor is not working. In this case, thawing of products may be observed in the freezer compartment.
- ⚡ Indicators on the panel. On modern models (Samsung RB37, LG GA-B489), when the compressor breaks down, an error often appears (for example,
E1orF5). Look for the decoding of the code in the instructions for your model. - 🕒 Operation cycles. Normally, the compressor should work 15–30 minutes, then turn off at 10–20 minutes. If it works without stopping or, conversely, turns on for a few seconds and turns off, this is an alarming signal.
Pay attention to capacitor (grid on the back wall of the refrigerator). If it hotbut the refrigerator does not freeze, the problem may be a freon leak or a clogged capillary tube. If the capacitor cold the compressor itself or the start relay is most likely faulty.
⚠️ Attention: If refrigerator turns on, but after 1-2 seconds turns off with a loud click, under no circumstances try to restart it manually (for example, by pressing the defrost button). This can lead to interturn short circuit windings!
2. Checking the compressor by winding resistance: instructions with photos
If a visual inspection does not produce results, it’s time to pick it up multimeter. This method allows you to identify winding breaks, interturn short circuits or breakdown to the body. To check, we will need:
- 🔧 Multimeter (even a budget model will do for 300–500 rubles).
- 🔌 Screwdriver (for removing the cover from the compressor).
- 📝 A piece of paper and a pen (to write down the readings).
Sequence of actions:
- Disconnect the refrigerator from the mains and wait until the capacitors will be discharged (5-10 minutes).
- Remove protective cover from the compressor (usually it is secured with 1-2 screws). Under it you will see 3 outputs:
C(Common) - general output;S(Start) - starting winding;R(Run) - working winding.
Ω (200 Ohm) and measure the resistance between the terminals:
C → S(start winding): 20–40 Ohm;C → R(working winding): 10–20 Ohm;S → R(total resistance): 30–60 Ohm.- Check breakdown to the housing: one multimeter probe to any pin, the second to the metal body of the compressor. The resistance should be infinite (on the screen
1orOL). If there is at least some value, the compressor is “broken” and must be replaced. - Connect refrigerator to the network via extension cord with grounding.
- Place current clamps on one of the power wires (phase or zero - it doesn’t matter).
- Turn on the refrigerator. In the first 1–2 seconds the current should jump to
1.5–3 A(starting current), then drop to0.5–1.2 A(operating current). - If the current exceeds 3.5 A and does not fall - in the compressor turn-to-turn short circuit. If the current equal to 0 is a winding break or a faulty relay.
| Refrigerator model | Resistance C→S (Ohm) |
Resistance C→R (Ohm) |
Resistance S→R (Ohm) |
|---|---|---|---|
| Atlant MXM 1705 | 25–35 | 12–18 | 37–53 |
| Indesit BIAA 13 | 30–40 | 15–20 | 45–60 |
| Samsung RL-34 | 20–30 | 10–15 | 30–45 |
| Liebherr CN 4015 | 35–45 | 18–25 | 53–70 |
If there is resistance between the terminals equals 0 (short circuit) or infinity (open), the compressor is faulty. Also an alarming signal - if the resistance S→R not equal to the sum resistance C→S and C→R (error allowed ±5 ohms).
Disconnect the refrigerator from the mains|Remove the protective cover from the compressor|Check the resistance between C→S, C→R, S→R|Measure the breakdown on the body|Check the readings with the table for your model-->
⚠️ Attention: On some modern models (LG with inverter compressors) conclusions can be marked differently:U,V,W. In this caseU→Vis the starting winding,V→Wis the working winding,U→Wis the total resistance.
3. How to check the compressor current: a method for experienced users
If the winding resistance is normal, but the compressor does not start, it is worth measuring starting and operating current. This method requires skills in working with electronics and current clamps or a multimeter with the function of measuring current up to 10 A.
Testing algorithm:
For models c inverter compressors (Panasonic NR-B, Hitachi R-WB) the operating current may be lower - 0.3–0.8 A. This is normal, since they consume less energy.
4. Diagnostics of the starting relay: why the compressor hums but does not start
Often the problem lies not in the compressor itself, but in starting relay a small device that is attached to the compressor housing and is responsible for starting it. If the relay is faulty, the engine will buzzingbut will not be able to start.
Signs of a faulty relay:
- 🔊 The compressor buzzes for 2-3 seconds and turns off with a click.
- ⚡ The relay body shows melted contacts or blackening.
- 🕒 The refrigerator turns on only after multiple attempts (sometimes it helps to knock on the relay).
- Remove the relay from compressor (usually it is mounted on latches or one screw).
- Shake it: if there is something inside rattles, it means that coil or the contacts have burned out.
- Ring the relay contacts in mode
Ωwith a multimeter. Between the terminals1–2(normally closed) the resistance should be 0 Ohm, between1–3— infinity. - Disconnect the refrigerator from the network.
- Remove the relay and find the contacts going to the compressor (usually these are
CandR). - Briefly connect them with a screwdriver with an insulated handle.
- Quickly connect the refrigerator to the network - the compressor should start.
- Connect blue hose the pressure gauge to service port (usually located on the tube going from the compressor to the condenser).
- Start the compressor. Normally, the pressure should be:
- 4–6 atm on the discharge side (red hose);
- 0.5–1 atm on the suction side (blue hose).
- If the pressure is below 0.3 atm is in the system lack of freon. If above 8 atm — clogging of the capillary tube.
How to check the relay:
If the relay is faulty, it can be replaced with a new one (cost - from 500 to 2000 rubles depending on the model). For refrigerators Atlant and Indesit universal relays are suitable RBM-1 or DANFOSS 103N0012.
How to temporarily start a compressor without a relay?
If the relay is burnt out and you don’t have a new one at hand, you can manually close the contacts for 1-2 seconds for the compressor to start. To do this:
5. Checking the pressure in the system: when you need to refill freon
If the compressor is working, but the refrigerator is not freezing, it is possible freon leakage. You can check this by pressure in the system, but for this. you will need gauge manifold (costs from 1500 rubles).
How to measure pressure:
Without a pressure gauge, the leak can be determined by indirect signs:
- 🧊 The condenser does not heat up (remains cold even after an hour of operation).
- 💧 Oil on the floor under the refrigerator (freon mixes with oil and flows out through microcracks).
- 🔍 Blackening of the tubes at the soldering points (a sign of corrosion).
⚠️ Attention: If you suspect a freon leak, Freon do not try to charge the system yourself. Freon R-600a (used in most modern refrigerators) is explosive! Contact a specialist with a license to work with refrigerants.
6. Typical compressor malfunctions and their “symptoms”
In the table below we have collected the most common breakdowns refrigerator compressors and their manifestations. This will help more accurately diagnose the problem.
| Malfunction | Symptoms | Possible causes | Repair method |
|---|---|---|---|
| Interturn short circuit | The compressor is heating up, but does not start. The protection is triggered after 1–2 seconds. | Winding insulation, overheating. | Replacement of the compressor. |
| Winding break | The compressor does not respond to switching on. ∞. | Mechanical damage, power surges. | Replacement of the compressor. |
| Piston jamming | The compressor hums, but does not rotate. | Bearing wear, dirt ingress. | Replacement of the compressor. |
| Freon leakage | The compressor works, but does not freeze. The tubes are covered with frost. | Corrosion of the tubes, cracks in the circuit. | Search for leaks, soldering, refilling. |
| Faulty relay | The compressor turns on after 3-5 attempts, clicks. | Burning of contacts, wear springs. | Replacement of the relay. |
If your refrigerator over 10 yearsand the compressor is out of order, think about the feasibility of repair. Replacement will cost 6000–15000 rubles (depending on the model), which is comparable to the cost of a used refrigerator For modern inverter ones. compressors (LG Linear, Samsung Digital Inverter) are often repaired impractical —they are difficult to find on sale, and the cost of spare parts reaches 70% of the price of a new refrigerator.
7. When to call a repairman: 3 cases when amateur activity is dangerous
Some compressor breakdowns can be repaired yourself (for example, replacing a relay or capacitor), but there are situations when it is better to contact professional:
- Leakage freon. For refilling you need special equipment and certificate to work with refrigerants. Incorrect refilling can lead to explosion (especially if freon is used R-600a).
- Compressor jamming. If the engine does not rotate, but only hums, it cannot be “rocked” or beaten - this can damage the windings. data-i="336">for diagnostics. special tool for diagnostics.
- Problems with the control board. On modern refrigerators (Samsung RB, LG Door-in-Door) the compressor is controlled by electronics. Self-repair of the board without a circuit and soldering equipment is practically possible. impossible.
The average cost of diagnosing a compressor by a technician is 1000–1500 rubles. If a replacement is required, be prepared for the following costs:
- 🔧 Replacement of the compressor: 6000–12000 rubles (excluding spare parts).
- 🔄 Refilling freon: 2000–4000 rubles.
- 🔌 Replacing the control board: 3000–8000 rubles.
⚠️ Attention: Repair prices may vary depending on the region and model of the refrigerator. In Moscow and St. Petersburg, the cost of work is 20–30% higher than in small cities. Always check the final price before starting repairs.
FAQ: Answers to frequently asked questions
Is it possible to check the compressor without removing it from the refrigerator?
Yes, most checks (winding continuity, current measurement, inspection relay) can be performed without dismantling. The compressor needs to be removed only for replacement or if access to the tubes is required (for example, for soldering in the event of a freon leak).
The compressor works, but the refrigerator does not freeze. What's the matter?
There may be several reasons:
- Freon leak (needs refilling).
- Clogged capillary tube (needs cleaning or replacement).
- Malfunction of the thermostat or sensor temperature.
- Fan failure (in models with No Frost).
First check whether the condenser is heating up (grid at the back). If not, most likely there is a problem with freon.
Which compressor is better: conventional or inverter?
Inverter compressors (LG Linear Compressor, Panasonic Inverter) have several advantages:
- 🔊 They work quieter (noise level 38–42 dB vs 45–50 dB for ordinary ones).
- ⚡ Save energy (20–30%).
- 🕒 Last longer (resource) up to 20 years against 10–15 years regular).
However, they more expensive to repair (spare parts are difficult to find), and they cannot be run without electronics. Conventional compressors are cheaper and easier to maintain, but less economical.
How much does a new compressor for a refrigerator cost?
The price depends on the model and type:
- Regular compressor (Danfoss, Embraco): 4000–8000 rubles.
- Inverter compressor (LG, Samsung): 10000–20000 rubles.
- Compressor for Soviet refrigerators (Minsk, ZIL): 2500–5000 rubles.
When purchasing, pay attention to marking (for example, Embraco EGX 90HLC) - it must match original. Also check whether it is included oil (for some models it needs to be purchased separately).
Is it possible to repair the compressor or just replace it?
B 90% of cases the compressor do not repairis replaced. Exceptions:
- Replacement start relay or condenser.
- Cleaning jammed shaft (if the compressor is not older than 5 years).
- Soldering tubes if there is a leak (if the housing whole). data-i="418">unjustified
Attempts to rewind windings or replace bearings usually unjustified - it's expensive and unreliable. Modern compressors (Embraco, Secop) non-separable.