Sudden stoppage of the refrigerator Ariston or the appearance of alarming clicks often indicates problems with starting the compressor. In most cases, the culprit of such a malfunction is the starting relay - a small but critical element of the motor's electrical circuit. It is he who is responsible for supplying voltage to the starting winding at the moment of switching on and then turning off this circuit when the engine reaches operating mode.
If you notice that the refrigerator is humming but does not start, or the compressor turns on for only a few seconds, after which a characteristic click is heard and silence sets in, you cannot ignore these symptoms. Long-term operation in this mode can lead to overheating and complete failure of the expensive compressor. Timely diagnostics and replacement of the relay is the most economical way to bring the equipment back to life without calling a technician.
In this article we will analyze the trigger mechanism in detail, consider the typical signs of its malfunction and provide a step-by-step algorithm for checking the part using a multimeter. You will learn how to safely remove the element, perform visual inspection and resistance measurements to accurately determine the need for replacement. Correct diagnostics will save time and money by avoiding the purchase of unnecessary spare parts.
The operating principle and design of the starting relay
The starting relay in refrigerators Ariston performs the function of an automatic switch. When the compressor motor starts, a significant starting current is required, which is supplied to the starting winding. As soon as the motor rotor reaches the required speed (usually about 75% of the rated speed), the relay opens the starting winding circuit, and the engine continues to operate on the working winding.
Structurally, most relays are a housing with contacts located inside and a moving mechanism. Depending on the refrigerator model, electromagnetic or posistor (thermal) relays can be used. Electromagnetic models respond to current strength by raising a core, which opens the contacts. PTC posistors, in turn, use the property of the material to sharply increase resistance when heated, which actually breaks the circuit.
It is important to understand that the relay also performs a protective function. If the compressor for some reason cannot start or seizes, the current in the circuit remains high. This leads to heating of the element (in thermal relays) or retention of the core (in electromagnetic ones), which ultimately breaks the power circuit, preventing combustion of the motor windings. Thermal relay often goes in conjunction with the starting one, forming a single protection unit.
⚠️ Attention: Before any manipulations with the electrical components of the refrigerator Ariston be sure to disconnect the device from the power supply. Working with a voltage of 220 volts without proper qualifications and tools can be life-threatening.
What is the difference between relays from different manufacturers?
Relays can differ in the shape of the case, the location of the contacts and the type of connection (vertical or horizontal). When replacing, it is important to select an analogue that fully matches the original in terms of markings and pin configurations, since there are no universal solutions, and incorrect installation can lead to a short circuit.
Typical signs of a faulty start relay
You can determine that the problem lies in the start relay by a number of characteristic symptoms that appear during operation refrigeration unit. The most obvious sign is the compressor cycling on and off. The motor tries to start, there is a loud click, the refrigerator twitches, but after 2-5 seconds it clicks again and goes silent. This cycle can be repeated every few minutes.
Another warning sign is a foreign smell of burning or melted plastic in the compressor area. This indicates that the contacts inside the relay have burned out or the housing has melted due to overcurrent. Visually, you can notice blackening, melting or traces of soot on the part, which clearly indicates the need for replacement.
Sometimes the refrigerator may work, but not reach the set temperature, or the compressor runs continuously without stopping. This may indicate that the relay contacts are “stuck” in the closed state, and the starting winding is constantly energized, which is unacceptable for normal engine operation. Also, a malfunction may be indicated by strong heating of the relay housing to the touch (after a short-term switching on).
- 🔊 The compressor clicks, hums, but does not start and immediately stalls.
- 🔥 There is a burning smell or visible smoke in the area of the engine compartment.
- 🌡️ The relay body gets very hot even after a short operating cycle.
- ❄️ The refrigerator does not freeze, although the compressor is trying to work.
It is worth noting that similar symptoms can be observed if the compressor itself (interturn short circuit) or the thermostat malfunctions. Therefore, a visual examination and analysis of symptoms is not enough - an instrumental check is required. Only comprehensive diagnostics will eliminate more serious and expensive breakdowns.
Preparation for diagnostics: tools and safety
To properly check the refrigerator start relay Ariston you will need a minimum set of tools. The main device will be a multimeter (tester), which allows you to measure resistance and test circuits for integrity. Without this device, it is almost impossible to carry out an accurate diagnosis, since the internal state of the contacts cannot be visually assessed.
You will also need screwdrivers (phillips and flat) to remove the rear panel of the refrigerator and dismantle the compressor protective casing. Some models Ariston may require pliers to carefully remove the terminals. A flashlight for good illumination of the engine compartment and a soft brush for cleaning the contacts from dust will not be superfluous.
☑️ Tools for checking the relay
Safety is priority number one. Make sure the refrigerator is completely unplugged. Not just turned off with a button, but removed from the socket. Capacitors in the circuit may retain a residual charge, so after removing the compressor cover, it is recommended to wait 5-10 minutes before touching the contacts. You should work in a dry room, preventing moisture from getting on electrical components.
⚠️ Attention: If you see that the wiring is melted or the insulation of the wires is broken, do not try to simply wrap them with electrical tape. It is necessary to replace damaged areas or terminals, as this may cause a fire.
Dismantling and visual inspection of the part
The dismantling process begins with removing the rear protective panel of the refrigerator, which covers the compressor and condenser grille. It is usually secured with several screws or latches. After removing the panel, you will gain access to the motor-compressor, in the lower or side part of which (depending on the model Ariston) there is a plastic casing attached.
Carefully remove the plastic casing by bending the clamps or unscrewing the screws. Below it you will see the start relay, which is placed directly on the three contact pins of the compressor. The relay can be additionally attached with a bracket or holder. Take a photograph of the location of the wires before disconnecting them, so as not to reverse the polarity during assembly.
Initial visual inspection often provides 50% of the information. Shake the relay near your ear: if you hear a ringing or knocking inside, it means the mechanism is destroyed or the armature has come off. Inspect the housing for cracks, melting, and blackening. If rust or oxidation is visible on the contacts, they can be carefully cleaned, but if the plastic is blackened, the part requires replacement.
Pay special attention to the condition of the compressor pins. If they are blackened or oxidized, this may prevent proper contact. In this case, they must be cleaned with fine sandpaper or a file. However, if the oxidation is deep, the problem may lie deeper, in a violation of the tightness of the unit.
Checking a relay with a multimeter: step-by-step instructions
To take measurements, switch the multimeter to resistance measurement mode (usually designated as Ω or 200 Ohm). First check the integrity of the coil (if the relay is electromagnetic). Connect the probes to the corresponding relay contacts. The device must show a certain resistance (usually from 30 to 200 Ohms depending on the model). If the device shows one (infinity) or zero, the coil is faulty.
Next, we check the contacts. In the initial position (the relay is not energized), the normally open contacts should show infinite resistance. Normally closed - zero (close to zero). To check the operation of the mechanism, you can carefully turn the relay over (simulating switching on), but it is more reliable to check it by testing it in different positions if the design allows access to the contacts without disassembling the case.
For posistor relays (with a heating element), the test consists of measuring the resistance between the contacts. It must be within the limits specified in the technical documentation. If the posistor is broken, the resistance will be zero; if it is broken, it will be infinite. The thermal relay is also checked: the bimetallic plate in a cold state should close the circuit.
| Test type | Normal readings | Fault symptom | Action |
|---|---|---|---|
| Coil resistance | 30 - 200 Ohm | 0 Ohm or ∞ (infinity) | Replacing the relay |
| Contacts (open) | ∞ (infinity) | 0 Ohm (short circuit) | Replacing the relay |
| Contacts (closed) | 0 - 2 Ohm | ∞ (open circuit) | Replacement of relay |
| Posistor | 10 - 50 Ohm (cold) | Sharp change or 0 | Replacement of the relay |
If the test reveals a discrepancy between the readings and the norm, the relay is considered faulty. Restoring it, as a rule, does not make sense due to the low cost of a new part and the complexity of a sealed assembly. Contact testing is the most reliable method that eliminates visual diagnostic errors.
Replacing the starting relay and test run
Replacing a relay is a simple procedure, but requires care. Buy a new part that is completely identical to the old one (the markings must match). Install the new relay on the compressor pins, observing the correct orientation (top-bottom indicated by the arrow UP or TOP). Place the wire terminals on the relay contacts according to the photograph taken earlier.
Fix the relay in the holder or casing. Make sure all connections are tight and nothing is loose. Reinstall the compressor protective cover. Only after complete assembly can you turn on the refrigerator. The first start may be accompanied by a louder hum, but after 5-10 seconds there should be a click when the starting winding is turned off, and the motor will go into a smooth operating mode.
After replacement, it is recommended to leave the refrigerator running for 2-3 hours without loading food to ensure stability of operation and the ability to gain temperature. Monitor the temperature of the new relay case: it may become slightly warm, but should not be so hot that it is impossible to touch.
⚠️ Attention: The technical characteristics of the relay may vary slightly depending on the year of manufacture of the refrigerator. Always check the markings on the body of the new part with the original. Using an unsuitable relay can lead to the compressor burning out.
What to do if the new relay also does not start the compressor?
If after replacing a working relay the situation has not changed (the clicks continue, there is no start), the problem is most likely in the compressor itself (turn-to-turn short circuit of the windings or a mechanical wedge). In this case, professional diagnostics are required by measuring the starting current and resistance of the motor windings.
Frequently asked questions (FAQ)
Is it possible to start an Ariston refrigerator without a starting relay?
Theoretically, you can start a compressor without a relay by manually applying voltage to the starting relay winding, but doing this is strictly prohibited in domestic conditions. This requires high qualifications, risks electric shock and is guaranteed to lead to combustion of the compressor, since the starting winding is not designed for long-term operation.
How much does a starting relay for an Ariston refrigerator cost?
The cost of a starting relay varies depending on the model and manufacturer of the spare part. On average, the price ranges from 300 to 1000 rubles. Original parts may cost more, but Chinese analogues are often not inferior to them in quality if the parameters are correctly selected.
Why does the start relay burn out?
The main reasons for failure are power surges in the network, frequent switching on and off of the refrigerator, overheating of the compressor due to poor ventilation or contamination of the condenser, as well as natural wear of contacts with time.
How often do you need to change the starting relay?
The starting relay is not a consumable item with a regulated replacement period. It lasts until it breaks. Under normal operating conditions and stable voltage in the network, a high-quality relay can operate for 10 years or more without intervention.