In modern electronic devices, cooling fans play a crucial role by circulating air to effectively dissipate the heat generated inside the device, ensuring that hardware components operate within an appropriate temperature range. However, when the cooling fan faces the problem of high temperature, its performance and stability will significantly decrease, and it may even cause equipment failure or complete shutdown. This article will delve into the reasons why cooling fans become difficult or unable to operate when the temperature is too high.

1. Thermal expansion and mechanical stress

Firstly, high temperatures can cause thermal expansion of the metal components inside the cooling fan, such as bearings and blades. This expansion may alter the gap and fit accuracy between components, leading to an increase in mechanical stress. In the long run, mechanical stress not only reduces the rotational efficiency of the fan, but may also cause increased wear and even jamming of components, making the fan unable to rotate normally.

2. Lubricating oil failure

The bearings in cooling fans usually require lubricating oil to reduce friction and improve operating efficiency. However, in high temperature environments, lubricating oil is prone to evaporation and deterioration, losing its original lubricating effect. This not only exacerbates bearing wear, but may also generate additional heat due to increased friction, forming a vicious cycle that ultimately leads to poor fan operation or stoppage.

3. Decreased motor performance

The motor of the cooling fan is its power source, and high temperature will directly affect the performance of the motor. The resistance of the coils inside the motor increases at high temperatures, resulting in more heat generated when current passes through, further exacerbating the temperature rise. Meanwhile, high temperatures may also cause aging of motor insulation materials, reduce insulation performance, and increase the risk of short circuits. These factors work together to reduce the efficiency of the motor, decrease the output power, and ultimately lead to a decrease in fan speed or complete stop.

4. Damage to control circuit

The control circuit of the cooling fan is responsible for adjusting the speed and operating status of the fan. In high-temperature environments, electronic components such as resistors, capacitors, transistors, etc. in circuits are prone to performance degradation or damage due to overheating. Especially when the temperature exceeds its rated operating range, the control circuit may experience logic errors, causing the fan to fail as expected or even completely malfunction.

5. Air flow obstruction

The operation of a cooling fan relies on the flow of surrounding air to remove heat. If the airflow around the fan is obstructed (such as dust accumulation, air duct blockage, etc.), even if the fan is still running, its heat dissipation effect will be greatly reduced. If left in this state for a long time, both the fan and the hardware it cools will experience an increase in temperature due to ineffective heat dissipation, exacerbating all of the aforementioned issues.

In summary, when the temperature is too high, the performance of the cooling fan will decrease or even fail to operate due to multiple factors such as thermal expansion, lubricating oil failure, motor performance degradation, control circuit damage, and air flow obstruction. Therefore, regular cleaning of dust, inspection and replacement of aged lubricating oil, ensuring good air duct design, and adopting efficient heat dissipation schemes are crucial for maintaining the normal operation and extending the service life of the cooling fan. Meanwhile, monitoring the temperature status of the equipment and promptly identifying and resolving potential issues is also a key measure to prevent the failure of the cooling fan due to high temperatures.