Is Your Auto AC System Producing Unusual Noises?

Is Your Auto A/C System Producing Unusual Noises?

From time to time, you may notice unusual noises coming from your auto A/C system. These issues are most likely to occur during summer, or whenever the air conditioning is heavily used. Like most car components, you’re A/C is subject to wear and the longer you use it the more likely you will encounter one or more of these noises. More than just a nuisance, these sounds can pinpoint potential problems with the unit, and if the air coming out of the vent is warm or nonexistent, this is another indication of trouble. While some of these issues are relatively straightforward and may be resolved DIY, others are complex and require the attention of a technician that is licensed.

Buzzing Sound

Buzzing usually occurs when the A/C system is first activated, and usually means that it is overcharged. Sometimes technicians or mechanics add excessive Freon during servicing, which will result in the AC not cooling adequately. Specifically, the buzzing occurs when the refrigerant enters the intake port of the compressor. Replacing the entire compressor is costly, so most mechanics will want to correct the issue in another way to reduce costs.

Rattling Sound

An air conditioner that rattles has numerous potential causes, making it tricky to determine for those who don’t specialize in them. It could be a sign that the compressor is failing, or that the serpentine belt has worn out. The problem could also be with a compressor clutch, which can wear out rapidly and must be replaced periodically. Depending on the make and model of the vehicle you drive, the compressor and clutch may need to be replaced simultaneously.

Squealing Sound

Squealing is one of the strangest sounds that an AC can make, and will definitely be noticeable to most drivers. It is typically an indication that your serpentine belt has issues. Technicians may attempt to resolve the problem by adding a belt dressing, but depending on its age and how worn out it is it may be better to simply replace the belt entirely.

Hissing Sound

This is probably the most common sound that most drivers will hear from their air conditioner. Hissing, especially when it occurs just after the car is shut off, simply means that pressure is being equalized, the result of Freon migrating from the compressor’s high pressure area down to the side that has lower pressure. Therefore, unlike the other sounds mentioned so far, hissing under these circumstances is totally normal.

Clicking And Knocking

This sound is one of the rarest, and is usually an indication that mounting bolts within the air conditioner have become loose. These bolts are used to secure multiple A/C components, and during engine operation the trouble spot can be identified by a visual inspection, as the loose components should be visible as they move about and shake. The simplest fix is usually to tighten your bolts and add a compound which is threaded locking.