When the AC button on the dashboard is on it actually starts the?

When the AC button on the dashboard is on it actually starts the?

recirculation button
It’s called the recirculation button, and it plays an important role in the heat. According to World Class Auto Service, the button is mainly used for the summer time. It helps your car get as cool as possible when you have the A/C on.

What causes air vents to stay in defrost position?

If you have an older car then the defroster system is controlled by using vacuum supplied by the engine. Lift the hood and inspect the vacuum hose or tube that leads from the intake manifold to the passenger’s side firewall. The image below shows a typical line break which causes the vents to stay in the defrost position.

How does the climate system control the defroster?

The climate system is responsible for controlling the position of the defroster actuator which is connected to the air position door in the heater plenum. This actuator controls defrost, middle and lower air vents. When it fails it can do so in the defrost position and must be replaced.

Where is the defroster located in an air conditioner?

The defroster is part of the heater and air conditioner system which is housed inside of the heater plenum. The vent control system for the defroster in integrated into the operation of all temperature controls and uses forced air provided by the blower motor.

Where does the vacuum line from the defroster go?

Vacuum lines travel from the vacuum control switch on the dash to vacuum servos under the dash. These servos move the air doors which turn on and off the defroster. If you can hear a hissing sound when the car is running from under the dash then vacuum is escaping.

How does the air vent work on a defroster?

The vent control system for the defroster in integrated into the operation of all temperature controls and uses forced air provided by the blower motor. On newer cars the vent direction and temperature controls are operated by a series of 3 or 4 electrical actuator motors which are adjusted by the climate control module.

The defroster is part of the heater and air conditioner system which is housed inside of the heater plenum. The vent control system for the defroster in integrated into the operation of all temperature controls and uses forced air provided by the blower motor.

The climate system is responsible for controlling the position of the defroster actuator which is connected to the air position door in the heater plenum. This actuator controls defrost, middle and lower air vents. When it fails it can do so in the defrost position and must be replaced.

Vacuum lines travel from the vacuum control switch on the dash to vacuum servos under the dash. These servos move the air doors which turn on and off the defroster. If you can hear a hissing sound when the car is running from under the dash then vacuum is escaping.

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