Starting the compressor is the most critical moment in the operation of any refrigeration equipment, and model brand Indesit here are no exception. It is in the first fractions of a second after switching on that the motor consumes the maximum amount of energy, which creates a colossal load on the apartment’s electrical network. Understanding what kind of starting current is typical for your unit is necessary not only for the correct selection of a voltage stabilizer, but also for diagnosing electrical wiring faults.
Many owners are faced with a situation where, when turning on the refrigerator, the circuit breaker in the panel is knocked out or the light in the entire apartment blinks. This is a direct consequence of the fact that the starting impulse exceeds the nominal values. Starting current can be 3-7 times higher than the working one, and ignoring this fact often leads to failure of expensive components.
In this article we will analyze in detail the physical processes that occur when the engine starts and determine standard values for various series of equipment. You will learn how to distinguish normal operation from the harbingers of a breakdown, and what precautions should be taken to extend the service life of your Indesit.
Physics of the process: why peak load occurs
When the compressor is turned on, the electric motor rotor is at rest. To move it and spin it up to operating speed, you need to overcome the inertia of the mass and the refrigerant pressure in the system. In this fraction of a second, the electric motor consumes the energy necessary to create maximum torque, which causes a sharp jump in consumption.
The design of the windings plays a significant role. In asynchronous motors, which are most often installed in classic models, the starting winding is activated for a short time. Start relay applies voltage to this particular coil, creating a phase shift to rotate the rotor. At this moment, the winding resistance is minimal, and the current reaches its peak value.
As soon as the rotor reaches about 75% of the rated speed, the centrifugal mechanism opens the starting winding circuit, and the engine goes into operating mode. The duration of this transient process is usually from 0.1 to 0.5 seconds, but it is during this period of time that the load on the network is maximum.
⚠️ Attention: If the starting relay is stuck in the closed state, the starting winding will not turn off after start. This will lead to rapid overheating and burning of the windings, since they are not designed for long-term operation.
Modern inverter models Indesit approach this process differently. The electronics smoothly accelerates the rotor, avoiding sharp jumps, however, even in them the initial impulse can be noticeable, although significantly smoothed out compared to the classics.
Standard values of the starting current for Indesit models
The value of the starting current directly depends on the power of the installed compressor and its type. For most household refrigerators Indesit medium capacity (250–350 liters), motors with a power of 100 to 140 W are used. The operating current of such motors is usually about 0.5–0.7 Ampere.
However, the starting indicator is much higher. On average, for standard single-compressor models the value briefly jumps to 2.5–4.5 Amps. If the refrigerator has a powerful compressor or a system No Frost with two fans that start simultaneously with the motor, the value can reach 5-6 Amperes.
It is important to distinguish between operating and starting current when selecting protective automatics. If you use a UPS or stabilizer, its peak power must withstand short-term overload without protection.
Below is a table with indicative values for various types of compressors often found in equipment of this brand:
| Compressor type | Operating current (A) | Starting current (A) | Pulse duration (s) |
|---|---|---|---|
| Standard (100-120 W) | 0.5 - 0.6 | 2.5 - 3.5 | 0.2 - 0.4 |
| Powerful (140-160 W) | 0.7 - 0.8 | 3.5 - 5.0 | 0.3 - 0.5 |
| Inverter | 0.4 - 0.9 (var.) | 1.5 - 2.5 | 0.5 - 1.0 |
| Two-compressor start | 1.2 - 1.4 | 6.0 - 8.0 | 0.4 - 0.6 |
It is worth considering that these values are averaged. The exact parameters of a particular engine are always indicated on the nameplate located on the rear wall of the unit.
Factors influencing an increase in starting load
A high starting current does not always indicate a malfunction. There are a number of operational factors that can enhance this effect. One of the main ones is the pressure in the cooling system. If the refrigerator has just been defrosted or has not been turned on for a long time, the pressure in the circuits is equalized, and it is easier to start the motor.
However, if the unit is turned off and immediately turned on, high pressure remains in the system. The compressor requires significantly more force to push the refrigerant. That is why operating instructions prohibits turning on the device earlier than 10-15 minutes after turning it off.
Why can’t you turn it on right away?
If you turn on the compressor immediately after turning it off, the oil in the system will not have time to drain into the crankcase, and the gas pressure will not will level out. This will cause the motor to run in a "stuck" mode, which will cause a huge starting current and can break valves or windings.
Ambient temperature also plays a role. In a hot room, the oil in the compressor becomes thinner, which reduces friction, but the viscosity of the refrigerant changes. In a cold room, the oil thickens, increasing resistance at start-up.
Wear of mechanical parts - the piston group and bearings - also leads to an increase in current. If the rubbing surfaces are damaged, it is more difficult for the motor to turn the shaft, and it consumes more energy to overcome friction.
Diagnostics of problems through analysis of current consumption
If you observe regular operation of automatic machines or knocking out plugs precisely at the moment of starting the refrigerator, this is a reason to carry out diagnostics. The first step should always be to visually assess the condition of the wiring and outlet. Melted plastic or a burning smell indicate that the contacts cannot withstand inrush currents.
For accurate measurements, you must use special current clamps with a Peak Hold function. A conventional multimeter in ammeter mode will not have time to record a short-term jump. The measurement is carried out on the compressor input cable.
⚠️ Attention: Carrying out measurements with current clamps under voltage of 220V is dangerous to life. If you do not have experience working with electrical appliances under load, it is better to call a specialist.
If the recorded current exceeds the norm by 2 or more times and the engine does not start, the thermal relay hums or immediately turns off, a defect in the motor itself or the starting device is likely. Frequent reasons are:
- ⚡ Interturn short circuit in the stator windings, which reduces the resistance.
- ⚡ Jamming of the piston group due to lack of oil or mechanical destruction.
- ⚡ Malfunction of the starting capacitor (in models with capacitor starting), which does not give the required phase shift.
It is also worth checking the voltage in the network. At low input voltage (less than 190V), the current in the motor windings increases, as the motor tries to compensate for the lack of power, which can lead to overheating and tripping of the protection.
Protecting the refrigerator from surges in voltage and current
To extend the life of your Indesit it is recommended to use devices protection. Simple network filters will not help here, since they are designed to smooth out high-frequency interference, and not to compensate for powerful surges of current or voltage.
The most effective solution is to install a voltage control relay (VCR). This device turns off the power if the voltage in the network is outside the permissible limits (for example, below 170V or above 250V), and turns it on again only after stabilization and expiration of a specified delay.
☑️ Selecting protection for the refrigerator
Voltage stabilizers are also useful, but you need to choose models with power reserves. If the operating current of the refrigerator is 1A, and the starting current is 5A, then the 500 VA (Volt-Ampere) stabilizer may not cope with the start-up and will go into error. It is recommended to take a stabilizer with a 3-4 times peak power reserve.
The turn-on delay deserves special attention. After a power surge or a short-term blackout, delay timer will not allow the compressor to start immediately. This is critical for equalizing the pressure in the system.
The role of the starting relay and its effect on starting
The starting relay is a small but extremely important unit that controls the starting process. Depending on the model Indesit, it can be posistor (solid-state) or inductive (with a coil and contacts). It is the serviceability of this element that determines how correctly the starting stage will proceed.
The posistor relay works on the principle of changing resistance when heated. When cold, it passes current to the starting winding, heats up and opens the circuit. If the posistor is broken, current flows constantly, causing humming and overheating. If it is broken, the motor will not start, there will only be a quiet hum.
Induction relays work mechanically. The current passing through the coil creates a magnetic field, which draws in the core and closes the contacts of the starting winding. As the rotor accelerates, the current drops, the field weakens, and the contacts open under the influence of gravity or a spring.
⚠️ Attention: When replacing a relay, it is important to maintain the orientation of the device. Many relays have an "UP" or "TOP" arrow. Installation upside down will cause the mechanics to malfunction and burn out the compressor.
A faulty relay is one of the most common reasons why the starting current becomes destructive. It either does not disconnect the starting winding or does not connect it at all, forcing the engine to operate in emergency mode.
Comparison of inverter and classic compressors at start
Technologies do not stand still, and in new models Indesit inverter compressors are increasingly found. Their operating principle is fundamentally different from the classic ones, which directly affects the characteristics of the starting current.
The classic compressor works on the principle of “turned on - worked - turned off”. Every start is stressful for the network and mechanics. The inverter motor does not turn off completely, but reduces the speed to a minimum, maintaining the temperature. Therefore, the concept of “starting current” for it is transformed into the initial acceleration current.
The advantages of the inverter system are obvious:
- 📉 No sharp current surges during each cooling cycle.
- 🔇 Silent operation and no clicks relay.
- 🛡️ Less wear on mechanical parts due to the absence of constant start-stops.
However, if the inverter refrigerator does turn off (for example, during defrosting or a power surge), its initial start-up still requires increased current, although the electronics tries to make this process as smooth as possible, gradually increasing the rotation speed rotor.
Practical recommendations for operation
To minimize the risks associated with starting currents and ensure long-term operation of your refrigerator Indesit, follow simple rules. Do not operate the device under extreme voltage conditions. If the light often “jumps” in your network, installing a voltage control relay is not a luxury, but a necessity.
Regularly check the tightness of the plug in the socket. Poor contact causes sparking and local heating, which is especially dangerous at times of high inrush currents. The socket must be in good working order, without any backlash or traces of carbon deposits.
When transporting the refrigerator, follow the rules: after transporting it in a lying position, let the unit stand for at least 4 hours (preferably a day) before turning it on. This is necessary so that the oil flows into the compressor. Switching on “dry” is guaranteed to lead to jamming and high starting current.
If you notice that the light in the apartment has begun to dim noticeably every time you start the refrigerator, or the machine in the panel begins to heat up, this is a signal that the load on the network is critical. In this case, you should not put off visiting an electrician or replacing the wiring.
Can I use an extension cord?
You can use an extension cord for a refrigerator only as a last resort and only a high-quality one, with a wire cross-section of at least 1.5 mm². It is STRICTLY PROHIBITED to use an extension cord wound into a coil - it will burn out at the starting current.
What is the starting current of the Indesit No Frost refrigerator?
For models with the No Frost system, the starting current is usually higher than with drip systems, since fans can start simultaneously with the compressor blowing The average value is 3.5–5.5 Amperes, depending on the power of the motor.
Why does the machine knock out when the refrigerator is turned on?
This happens if the rating of the machine is too small for the starting current (for example, a 6A machine with a peak of 7A) or if there is a short circuit in the circuit. Also, the reason may be a malfunction of the compressor itself (interturn short circuit).
Is a stabilizer needed for the new Indesit?
Modern refrigerators have a wide range of operating voltages, but starting currents remain high. A stabilizer is desirable in homes with an unstable network in order to protect the control electronics and reduce the load on the windings at low voltage.
How to find out the power of the compressor?
Look at the sticker (nameplate) on the back wall of the refrigerator. It shows the model, refrigerant type, operating current and sometimes starting current. The power can be approximately calculated by multiplying the voltage (220V) by the operating current, but it would be more accurate to look at the compressor model in the specification.