When the refrigerator stops starting, but When this produces a characteristic buzzing or clicking sound, experienced technicians first suspect problems in the compressor starting electrical circuit. Starting capacitor plays a critical role in this process, providing the necessary phase shift to start the engine. Understanding where exactly it is located is the first step to self-diagnosis and repair of household appliances.
In most modern and classic models, this part is hidden inside a protective casing, which is attached directly to the compressor housing. Access to the node often complicated by the design features of the rear wall of the unit, but with With proper preparation, finding the element will not be difficult. It is important to understand that without disconnecting the device from the network, it is strictly prohibited to carry out any manipulations.
In this article we will look in detail at what the starting element looks like, where to look for it on different types of compressors and what precautions must be taken. The starting capacitor in household refrigerators most often has a capacity of 30 to 100 uF and an operating voltage of 250-450 Volts, which makes it potentially dangerous if handled carelessly even after turning off the device.
Functional purpose and principle of operation
To effectively search for a part, you need to understand why it is needed. A single-phase asynchronous motor installed in a compressor is not capable of independently creating a rotating magnetic field to start the rotor. To do this, it requires a second winding, connected via starting capacitor. It is this element that creates the phase shift that allows the engine to gain initial speed.
Unlike the working capacitor, which can remain in the circuit constantly, the starting element is turned off immediately after the engine reaches a certain rotation speed (usually about 75% of the nominal). This is done by the starting relay. Operating time The starting capacitor is calculated in seconds, but the load on it at this moment is colossal.
⚠️ Attention: If the capacitor is swollen or electrolyte has leaked from it, this indicates a serious breakdown. An attempt to start a refrigerator with a damaged element can lead to burnout of the compressor windings.
Frequent on and off cycles, voltage surges in the network and temperature changes in the compressor niche - all this shortens the life of the component. That is why it fails more often than the motor-compressor itself. Understanding its role helps to quickly diagnose the problem: if the motor hums but does not start, and the relay clicks, this is often the culprit.
Typical location on different types of compressors
The answer to the question of where the starting capacitor is located depends on the type of compressor installed in your refrigerator. The vast majority of older and many new models use piston units. In them, all starting fittings, including starting relay and the capacitor, are enclosed in a plastic or metal casing attached to the side pin of the compressor.
In inverter refrigerators, the situation can be radically different. There, the motor is controlled through an electronic unit, and the classic capacitor can be located inside the inverter board, which is often located separately from the compressor itself, for example, in the lower part of the case or in a special compartment. Linear compressors LG also have their own specific placement of control electronics.
For classic models, the search algorithm is simple: move the refrigerator away from the wall, remove the rear metal panel (crankcase) bottom part. You will see a black “tank” - this is the compressor. A box will be attached to the side or top of it. Inside this box, in close proximity to the relay, is the required element. Sometimes it can be taken out separately and mounted on the wall of a niche or frame, but connected by wires to a relay.
Step-by-step instructions for accessing the part
Before starting any work, make sure that the refrigerator is disconnected from the power supply. Remove the plug from the outlet. This is the first and most important safety rule. Next, you will need a Phillips screwdriver and possibly pliers to remove the clamps.
- Remove the rear protective panel at the bottom of the refrigerator. It is secured with screws or latches.
- Inspect the area around the compressor. Locate the plastic or metal casing on the side or top of the unit.
- Carefully remove the casing. It can be held on by spring clips or screws. Do not pull sharply so as not to damage the wires.
- Inside you will see a starting relay (a black box that fits over the contacts) and next to it there is a cylindrical or rectangular element with two or three terminals.
☑️ Safety check before repair
If the capacitor is not visually found in the casing, trace the wires coming from the relay. They can lead to an element mounted on the metal frame of the refrigerator or on the wall of a niche. In some models Indesit or Atlant the capacitor may be taped to the tubes with electrical tape or secured with a clamp.
To remove the element, you may need to disconnect the wires. Before doing this, it is strongly recommended to take a photo of the connection diagram or mark the wires with a marker so as not to mix up the contacts during assembly. An error in the connection can lead to a short circuit.
Visual signs of element malfunction
Before taking complex measurements with a multimeter, it is worth conducting a visual inspection. Deformation of the case is the most obvious sign of failure. If the capacitor is swollen, becomes like a barrel or has lost its cylindrical shape, its performance is in question.
Pay attention to the condition of the leads and wires. The presence of burning marks, melted plastic or black deposits on the body indicate overheating and breakdown. Also, a sign of a malfunction may be leakage of electrolyte - an oily liquid from under the valve at the end of the part.
| Symptom | Probable cause | Action |
|---|---|---|
| Bloating of the body | Overheating, power surge | Replacement is required |
| Electrolyte leakage | Depressurization, aging | Replacement is required |
| Fusing of contacts | Poor contact, sparking | Cleaning and replacement |
| External integrity | Internal breakage of plates | Checking with a multimeter |
However, the absence of external damage does not guarantee serviceability. A capacitor may look perfect, but have a critical loss of capacity or an internal break. Therefore, visual inspection is only the first stage of diagnosis.
Diagnostics with a multimeter and checking capacitance
For accurate diagnostics, you will need a multimeter with a mode for testing capacitors or measuring resistance. Before checking, be sure to discharge the element by shorting its terminals. If the capacitor is charged, you may damage the device or receive an electric shock.
Switch the multimeter to resistance (ohms) measurement mode. Touch the leads to the leads. The needle on the analogue meter should deflect and slowly return back. On a digital multimeter, the readings will change from smaller to larger, going to infinity. If the device shows zero, there is a short circuit, if immediately infinity, there is a break.
⚠️ Attention: Checking the capacitor without soldering (in situ) often gives incorrect results due to the influence of other circuit elements. For an accurate diagnosis, it is better to disconnect the part from the circuit.
The most accurate method is measuring capacitance. If 30 µF is written on the case, and the device shows 15 µF or 50 µF, such an element must be replaced. The permissible deviation is usually no more than 20% of the nominal value. Loss of capacity leads to the fact that the engine does not have enough starting torque, and it either does not start or operates with overload.
Replacement rules and selection of analogues
When When purchasing a new element, it is critical to comply with the parameters of the old one. The main importance is the capacitance (uF) and operating voltage (V). You can install a capacitor with a higher voltage (for example, 450V instead of 250V), but the capacitance must match as accurately as possible.
Installing an element with a lower capacitance will lead to problems with starting, and with a larger one - to overheating of the motor windings. Capacitor type also important: special non-polar electrolytic capacitors designed for operation are used for starting circuits in alternating current circuits.
Is it possible to use a working capacitor instead of a starting capacitor?
Theoretically, it is possible if its capacitance and voltage are the same. However, starting capacitors are optimized for short-term operation under high load, and working capacitors are optimized for permanent use in the circuit. In an emergency, replacement is possible, but it is better to use specialized starting models.
The installation process is simple: connect the wires in the same order as they were connected previously. Securely secure the element with a clamp or clip so that the vibration of the compressor does not break the wires. After assembly, check the operation of the refrigerator: it should start the first time without a long hum.
Frequently asked questions and answers (FAQ)
Is it possible to start a refrigerator without a starting capacitor?
No, it is impossible to start a single-phase asynchronous motor without a starting element (or a starting device that creates a phase shift). The compressor shaft will only hum and twitch, but there will be no rotation. Holding the start button manually for a long time will also not help and can burn the windings.
Why does a new capacitor burn out immediately after installation?
There may be several reasons: incorrectly selected capacitance, low operating voltage of the new element, or a malfunction of the starting relay itself, which does not turn off the winding after start. It is also worth checking the voltage in the network - strong surges can break through the protection.
Where can you find the capacitance markings on the capacitor?
The markings are usually applied to the side surface of the case. Look for the number with the designation µF or mF (microfarads) and voltage in Volts (V). If the markings are erased, the parameters can be found in the technical documentation for the refrigerator or on the diagram pasted inside.
What is the difference between the starting and running capacitor in the refrigerator?
The starting capacitor is turned on only at the time of startup (for 1-3 seconds) and has a large capacity. The worker can remain on the circuit constantly, helping the motor run more efficiently, and has a lower capacity. Most household refrigerators use only a starting capacitor, or the system starts without it (via a relay), but powerful models can have both types.