If you keep your car's air conditioning on without the engine running or the alternator charging, several things can happen:
Battery Drain: The air conditioning system requires a significant amount of electrical power to operate. Without the engine running or the alternator charging the battery, the electrical load of the air conditioning system will rapidly drain the battery. The battery's capacity to provide electrical energy is limited, and running the air conditioning for an extended period can deplete the battery, potentially leading to a dead battery.
Inadequate Cooling: Without the engine running, the air conditioning system cannot operate at its optimal capacity. The compressor, which is driven by the engine, plays a crucial role in cooling the air. Without the compressor functioning, the air conditioning system will struggle to produce cold air, resulting in inadequate cooling or no cooling at all.
Overheating: Running the air conditioning system without the engine running can cause the car to overheat. The engine's cooling system, including the radiator and cooling fans, relies on the circulation of coolant and proper airflow generated by the engine running. When the engine is off, there is no coolant circulation or airflow, which can lead to overheating of the engine.
System Damage: Continuous operation of the air conditioning system without the engine running can potentially damage various components. The compressor, for example, relies on a lubrication system that is driven by the engine's oil circulation. Without the engine running, the compressor may not receive proper lubrication, resulting in damage to the compressor and other related components.
To avoid these issues, it is best to turn off the air conditioning system when the engine is not running or the alternator is not charging. It is also advisable to follow the manufacturer's guidelines and recommendations for operating the air conditioning system to ensure its longevity and prevent any potential damage.