Why A Laptop Fan Turns On When It’s Charging

Laptop fans are designed to activate to cool the system when needed, not necessarily due to overheating. For instance, you may notice the fan kicks in more often when the device is charging. This behavior is generally due to increased demands on the system that lead to higher temperatures.

This article explains the underlying causes of this phenomenon and provides guidance on how to manage or mitigate the issue.

Increased Processor Activity When Plugged In

When plugged into a power source, laptops often run at higher processing speeds compared to battery mode. This is because the energy constraints are less restrictive, allowing the CPU to operate at higher capacities which generates more heat, thereby activating the fans.

Understanding Processor Demand

  • Performance Enhancement: On AC power, the CPU can achieve maximum performance levels, increasing heat output.
  • Cooling Requirements: Higher performance necessitates more effective cooling, hence the fan activation.

Active System Cooling Policy

Windows devices typically have two cooling policies: active and passive. The default setting when plugged in is usually ‘active’, which might cause the fan to start immediately upon charging.

How to Adjust Cooling Settings

  1. Go to Control Panel > Hardware and Sound > Power Options.
  2. Click on Change plan settings next to your selected power plan.
  3. Click on Change advanced power settings.
  4. Expand the Processor power management section, then System cooling policy.
  5. Set ‘Plugged in’ to Passive to reduce fan activity, opting for slower processor speeds instead of higher fan speeds.

High Power Consumption and Heat Generation

Charging the laptop battery while running it can significantly increase power consumption and heat generation, prompting the cooling fans to activate.

Tips to Manage Power Consumption

  • Reduce screen brightness.
  • Close unnecessary applications.
  • Disconnect unneeded peripherals that may draw power.

Running Intensive Applications and Background Processes

Heavy software applications and numerous background processes can strain the system’s resources, increasing temperature and triggering the cooling fans.

Managing Applications

  • Close unnecessary programs.
  • Limit startup programs through Task Manager.
  • Regularly check for and close resource-intensive background processes.

Optimal Performance Settings and Hardware Demands

Setting your laptop to high performance increases power consumption and heat production, often resulting in fan activation to manage increased thermal output.

Adjusting Performance Settings

  • Access Power Options in the Control Panel.
  • Choose a balanced or power saver plan when on battery to reduce heat and fan usage.

Environmental Factors and Maintenance

External conditions such as a hot room or blocked air vents can exacerbate the need for active cooling. Regular cleaning of vents and fans can help maintain optimal cooling efficiency.

Regular Maintenance Tips

  • Keep vents clear and unblocked.
  • Clean dust from air intakes and fans periodically.
  • Use your laptop on hard, flat surfaces to enhance air circulation.


The activation of your laptop’s fan when charging is typically a normal response to increased power usage and heat generation. By managing your system’s power settings and environmental conditions, you can help control fan behavior. Regular maintenance and mindful usage can significantly impact the cooling efficiency and overall performance of your laptop.

This guide should provide a comprehensive understanding and solutions for managing your laptop’s fan activity, especially when charging, to enhance both performance and user experience.