What an Actuator Does

Modern vehicles control their climate control systems using actuators.  For the purpose of this article, we are talking about automotive climate control actuators.  These actuators are electrically powered, and control the flow of air throughout the cabin of the vehicle.  

Actuators control and direct the flow of air throughout your vehicle

What Actuators Do

What an Actuator Does

Actuators control and direct the flow of air throughout your vehicle.  They take input from you (or your vehicle’s computer).  They open and close paths that the air can flow through.  The blend door actuator controls the temperature in the vehicle.  Think of them like gates.

When you go to run your car in the winter time, you’ll probably change it from the standard heater setting to defrost in the morning.  When you do this, you tell the actuators to redirect the flow of air to the defroster.  When actuators go bad, they won’t be able to control the flow of air, which leads to an uncomfortable cabin.

Actuators replaced the manual levers that were previously used in vehicles.  While a direct lever might be simpler than an actuator, actuators have two main benefits that make them desirable over manual operation of the A/C system.

  1. Ease of Use– When you change the climate control settings on a modern car, it’s an effortless experience.  Once you flick the switch, the actuators get to work and that is really all the effort that goes into it.  With a manually controlled system, you need to make the controls big enough to provide the proper leverage to manipulate the blend door.  This is disadvantageous from a design point and for ease of use.
  2. Automatic Climate Control– With actuators, you can set the temperature in the vehicle like you do at home.  This allows you to spend even less time thinking about the temperature inside of the vehicle, and more time focussed on the road.  The actuator can be controlled by the vehicles computer, which wouldn’t be possible without them.



An actuator is a small electric motor that controls the air flow and temperature throughout the vehicle.