Should the air conditioning be turned off before shutting down the engine?
4 Answers
Turn off the air conditioning before shutting down the engine. If you turn off the engine first and then turn on the air conditioning, the next time the vehicle starts, the engine will start with the load of the air conditioning, and such a high load will damage the engine. Additional information: The principle of car air conditioning: The working principle of car air conditioning The car air conditioning refrigeration system consists of a compressor, condenser, liquid storage dryer, expansion valve, evaporator, and blower, among others. The components are connected into a closed system using copper pipes (or aluminum pipes) and high-pressure rubber hoses. The compression process of car air conditioning: Compression process The compressor sucks in the low-temperature and low-pressure refrigerant gas at the outlet of the evaporator and compresses it into high-temperature and high-pressure gas, which is then discharged from the compressor.
I've developed the habit of turning off the air conditioning before shutting down the engine, a practice rooted in years of driving experience. Leaving the AC running when directly turning off the ignition forces both the engine and AC compressor to start simultaneously upon next startup, placing extra strain on the battery which could lead to premature failure. Compressor components may also wear faster, particularly noticeable during summer heat, potentially causing unpleasant odors or reduced cooling efficiency. Since adopting this simple routine, I've noticed smoother engine starts and significantly lower maintenance costs. Remember to regularly inspect AC filters and systems to maintain efficiency. Combined with the pre-shutdown AC switch-off habit, this naturally extends your vehicle's lifespan.
From a technical perspective, it's wise to turn off the air conditioning before shutting down the engine. When the AC is running, the compressor is driven by the engine. Turning off the engine directly leaves pressure in the system, causing an excessive load during the next startup, which can damage the battery and accelerate component aging. I recommend turning off the AC one or two minutes before parking to allow the system to transition smoothly. Consistently following this practice protects the electrical circuits and reduces unnecessary maintenance issues. Regular AC maintenance should also not be neglected, otherwise the benefits from good habits could be offset.
I always turn off the air conditioning before shutting down the engine. If not turned off, it puts more strain on the car during the next startup, especially on the battery, which can affect overall health over time. A simple action can prevent these issues and help maintain the air conditioning system in optimal condition. If the air conditioning often has unpleasant odors, this habit can often alleviate the problem. Once developed, it makes driving more reassuring.
