The question of how long it takes to start refrigeration equipment after it is turned off is one of the most common among owners household appliances. This is not just a whim of manufacturers, but a strict requirement dictated by the physical and chemical processes occurring inside the cooling system. Ignoring these time intervals can lead to expensive repairs or complete replacement of the unit.
Situations that require turning off the device are different: planned defrosting, general cleaning, moving to a new apartment or a sudden power outage. In each of these cases, the algorithm of actions and the waiting time before restarting can vary significantly. Compressor and the refrigerant require special attention, since they are the heart of the refrigerator.
In this article we will analyze all possible scenarios and explain why haste in this matter is strictly contraindicated. You will learn how to properly prepare equipment for operation so that it lasts for the period stated by the manufacturer without failures.
⚠️ Attention: Violation of operating rules, in particular, early start of the compressor, is a common reason for refusal of warranty service. Service centers can easily determine the fact of incorrect switching on by the state of the oil in the system.
Physical processes when turning off and on
To understand the need for a pause, you need to understand the structure of the refrigeration system. Freon circulates inside the circuit, which transfers heat. To move it, a compressor running on special synthetic or mineral oil is used. When the device is operating, some of this oil inevitably enters the cooling circuit in the form of a fine suspension, but in normal mode it manages to flow back into the compressor crankcase. refrigerant (freon), which transfers heat. To move it, a compressor running on special synthetic or mineral oil is used. When the device is operating, some of this oil inevitably enters the cooling circuit in the form of a fine suspension, but in normal operation it manages to flow back into the compressor crankcase.
At the moment of shutdown, especially if this happened while the engine was running, the pressure in the system remains high, and the oil is distributed unevenly across different sections of the pipeline. If you start the engine right away, it will try to compress the refrigerant gas along with the liquid oil that has entered the cylinders. The fluid does not compress, which leads to water hammer. This mechanical damage to the piston group often becomes fatal for the compressor.
In addition, with a sharp start without preheating and stabilizing the pressure, the motor operates in overload mode. Starting currents at this moment can exceed the rated values several times, which creates a critical load on the motor windings and the starting relay. That is why a pause is necessary for the natural drainage of oil and equalization of pressure in all parts of the circuit.
What is water hammer in a compressor?
Water hammer is a sharp increase in pressure in the compressor cylinder due to the presence of an incompressible fluid (oil or liquid refrigerant). As a result, the valves become deformed or destroyed, and the connecting rod can puncture the cylinder block. Repair in this case is often not economically feasible.
Waiting time after defrosting and cleaning
Scheduled defrosting is the most common reason for temporary shutdown of the refrigerator. During the defrosting process, you remove the ice crust and wash the inner chambers. The main task here is not only to allow the water to drain, but also to completely dry the unit, and also allow it to cool or warm up to room temperature if warm water was used.
If you washed the refrigerator with warm water, the inner walls and, more importantly, the evaporator could get hot. A sudden start of the compressor on a “hot” evaporator will create a huge difference in temperature and pressure. This will cause the motor to work without stopping, trying to cool the volume, which can cause it to overheat and turn off by the thermal relay.
The optimal waiting time after complete defrosting and washing is from 2 to 4 hours. During this time, moisture from electrical contacts and seals will have time to evaporate, and the temperature inside the chambers will be equal to room temperature. You should not rush things, even if the unit seems dry outwardly.
☑️ Correct defrosting
There is a myth that modern systems No Frost do not require defrosting. This is not entirely true: they also need to be turned off periodically for hygienic cleaning and drainage holes that can become clogged with dust and mold. The waiting rules for them are the same as for drip systems.
Rules for starting after transportation
Transporting a refrigerator is stressful for equipment, comparable to an earthquake for a building. During transportation, especially if the device had to be tilted more than 40 degrees, oil from the compressor is guaranteed to flow into the cooling circuit and even into the evaporator. In this case, the question “how long before you can turn it on” becomes critically important.
If the refrigerator was transported in an upright position and not shaken excessively, it is enough to let it stand for 2-3 hours. This time is enough for the oil to flow into the crankcase and the refrigerant to become liquid. However, if transportation took place in a lying position or with strong bends, the waiting time increases to 8-12 hours, and ideally - up to a day.
An attempt to turn on the refrigerator immediately after bringing it into the apartment is fraught with the fact that the compressor will start “dry” or with an oil plug. In the first case, accelerated wear of the rubbing parts occurs, in the second - water hammer. None of these scenarios bode well for the longevity of the equipment.
| Method of transportation | Inclination angle | Recommended settling time | Risk of breakage |
|---|---|---|---|
| Vertical | Up to 40 degrees | 2-3 hours | Low |
| Vertical | More than 40 degrees | 4-6 hours | Medium |
| Recumbent position | 90 degrees | 12-24 hours | High |
| Strong shaking | Any | At least 8 hours | High |
Actions after power surges
Instability of the power grid is the scourge of many regions. If the light blinked or there was a complete power outage, the refrigerator could turn off at the most inopportune moment in the cycle. Modern models are equipped with protection, but it works with a delay. Your task is to prevent re-starting at the moment of unstable voltage.
During a short-term surge or shutdown for 1-2 minutes, the compressor may not have time to stop the inertia of the shaft rotation. Reapplying current at this point will cause the motor to run against rotation, which will lead to burnout of the windings. That is why the design of many refrigerators includes a thermal time relay, which prevents the motor from starting earlier than 3-10 minutes after stopping.
However, relying only on the built-in protection is risky. If the power surge was strong, you could suffer electronic control module. In such cases, it is recommended to pause for at least 15-20 minutes before turning on to ensure that the network parameters have stabilized. The ideal solution would be to use a voltage stabilizer.
⚠️ Attention: If, after turning on, the refrigerator makes a hum but does not start, or, conversely, operates silently but does not cool, immediately disconnect it from the network. These are signs of a serious malfunction that requires diagnostics by a technician.
The influence of the type of refrigerant and compressor
Different models of refrigerators use different types of refrigerants (freon) and compressors, which may make adjustments to the waiting time recommendations. For example, older models running on R12 or R600a freon are more sensitive to the presence of moisture and oil in the circuit than modern analogues.
Inverter compressors require special attention. They operate on the principle of smoothly changing the shaft speed without completely switching off in normal mode. If such a device has been de-energized, starting it requires a particularly thorough check of the electronics. Although their mechanical part is more reliable, the electronics are afraid of jumps when turned on.
Refrigerators with the system No Frost are characterized by the presence of additional fans and heating elements. When turned on after a long period of inactivity, all these elements begin to work simultaneously, creating a peak load on the network. Therefore, a pause of 3-4 hours will allow not only the oil to drain, but also the entire system to “realize” the need for work.
Typical mistakes when starting up for the first time
The most common mistake is the desire to immediately check the functionality of the equipment. People turn on the refrigerator, load it with food and slam the door. This is absolutely not possible. The refrigerator must run idle for at least 1-2 hours (preferably more) to gain operating temperature and stabilize the cycles.
The second mistake is installing the device close to the wall immediately after it has been installed. For normal operation, the compressor needs heat exchange. If the radiator on the rear wall overheats due to lack of ventilation, the motor will wear out. Leave a gap of at least 10-15 cm from the wall.
The third mistake is ignoring the level. If the refrigerator is placed on an uneven floor, the compressor experiences vibration loads, the oil may foam and make it worse for it to return to the crankcase. Before turning on for the first time, be sure to adjust the support legs to the level.
Frequently asked questions (FAQ)
Is it possible to reduce the waiting time if it is really necessary?
No, it is physically impossible to reduce the waiting time without the risk of breakdown. Oil has a certain viscosity and flows at a certain speed. No traditional methods (knock on the compressor, tilt in different directions) guarantee the return of oil to the crankcase and can damage the tubes.
What will happen if you turn on the refrigerator 30 minutes after transportation?
With a high degree of probability, a water hammer or start-up without lubrication will occur. The compressor may burn out instantly or fail after several months of intensive use. Repairs will cost 50-70% of the cost of a new refrigerator.
Do you need to remove food before turning it on for the first time after defrosting?
Yes, definitely. You can load food only after the refrigerator has run idle for 2-3 hours and reached the set temperature. Otherwise, the load on the compressor will be excessive, and the products may spoil due to long cooling.
Does the time of year affect the waiting time?
Yes, it does. In winter, if the refrigerator was transported in cold weather, it must be kept in a warm room and turned off for at least 4-6 hours (preferably a day) before turning it on. This is necessary so that the condensation formed inside on the cold parts completely evaporates and does not cause a short circuit.
Does the refrigerator hum immediately after turning on?
Immediately after turning on the compressor may work louder than usual, since it starts with maximum power to cool the empty chamber. This is fine. However, if the hum is accompanied by knocking, vibration or whistling, the unit must be turned off.