What is the reason for the belt noise when turning on the AC that stops after a while?
2 Answers
This is a fault caused by the smooth wear of the contact surface between the belt and the pulley. Here are the relevant details: 1. Car Air Conditioning: The car air conditioning system is used to regulate and control the temperature, humidity, air cleanliness, and airflow inside the car cabin to the optimal state, providing a comfortable riding environment for passengers and reducing travel fatigue. It also creates good working conditions for the driver and plays an important role in ensuring safe driving. 2. Timing Belt: The timing belt is an important component of the engine's valve system. It connects to the crankshaft and ensures accurate intake and exhaust timing through a specific transmission ratio. Belts are used instead of gears for transmission because they produce less noise, have minimal self-variation, and are easy to compensate for.
My own car occasionally makes a brief squealing noise from the belt when the AC is turned on, then quiets down. This is usually caused by a slightly loose belt or slipping due to a humid environment. When the AC compressor kicks in, it increases the load, and the belt needs a moment to adjust to the tension. If a new belt is installed slightly too tight or an old belt is a bit loose, the friction-generated heat causes it to expand and grip properly, stopping the noise. Ignoring this can lead to premature belt wear or reduced AC efficiency, compromising driving safety. It's recommended to inspect the belt every six months for cracks or excessive looseness and adjust it promptly to avoid unexpected breakdowns. Simple maintenance can save significant costs—don’t wait until it becomes severe. This issue is more common in winter due to higher humidity and less frequent in drier summer conditions, but staying vigilant is always wise.
