When you turn on your car air conditioning you will want to hear that smooth humming sound as you hit the road. But what if you hear your car air conditioner clattering? Any unusual sound from your air conditioning is not only annoying but can also be a great cause of concern. It could be just a simple problem like foreign debris caught between the ac slats or more serious problems like the issues with the blower motor, failing belt tensioner/serpentine belt in your engine, or worn out compressor among other things. We will talk about car air conditioner clattering in detail in this article.
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From squealing, buzzing, knocking, hissing to clattering noise — you can get an idea of what could be wrong with your air conditioning by the kind of strange sounds it’s making. The different sounds may share the same problem but still it’s helpful to narrow down the possibilities when you troubleshoot.
As mentioned, your car could make a loud squealing noise. It can get worse when starting the car or turning on the air conditioning, this one usually indicates a serpentine belt issue. Examine the belt. If it appears to be broken or dried, it should be replaced. You may need to replace your car anyway if it is older. Consult the owner's manual for suggestions.
The AC compressor makes a buzzing noise, which is usually caused by the system being overfilled. Too much coolant in the system might harm it, resulting in costly and time-consuming repairs. Get this one checked out as soon as possible if you hear it.
The most straightforward to diagnose and repair is a knocking or clicking sound coming from the air conditioner. A loose mounting bolt on your AC compressor or somewhere in the system is most likely to blame. While the engine is still cool, examine and shake each of the mounting bolts. Tighten them if they're loose, being careful not to over tighten them.
A hissing sound on the other hand is actually completely common and normal. This happens as soon as the air is turned off. It's the sound of coolant moving from the high-pressure to the low-pressure side of the system.
A constant hissing or whistling sound, on the other hand, could indicate a refrigerant leak. You could have a refrigerant leak in your refrigerant lines or in your internal valve. A bubbling sound can also be caused by leaking refrigerant lines. If left unchecked, leaky internal valves will worsen, and the hissing sound will become louder. If you want to stay cool and avoid the leak from getting worse, you should inspect and fix it as soon as possible. If you suspect a leak, turn off the air conditioner.
And finally the air conditioner clattering, which is something you should get checked out as soon as possible. This could be a sign that a compressor is going to break down. It could be a sign that parts have come loose anywhere in the system. These could break loose and cause damage to other components in the process.
Sources of Car Air Conditioner Clattering Noise
Here are the 7 common reasons you may be experiencing car air conditioner clattering:
- The Blower Motor
The blower motor in your car might be found in one of two places. By opening the glove box and peering behind it, you may usually find it on the passenger side of the vehicle. Otherwise, manufacturers may conceal the unit beneath the glove box with a plastic covering. The alternative place is beneath the hood, on the passenger side, at the base of the firewall. A huge cylinder with a plate connecting the blower motor to the cylinder can be found there. Replace the blower motor if it rattles when the car is idling.
- Belt Tensioner
The most common cause of car air conditioner chattering is a belt tensioner. Fortunately, it's not difficult to replace. The tensioner is a component in the front of your engine that keeps the serpentine belt that drives the air conditioner pulley as tight as possible. The spring in the tensioner can eventually fail, resulting in a rattling sound.
- Serpentine Belt
The engine, alternator, power steering pump, water pump, and air conditioner compressor are all driven by the serpentine belt of an automobile. This is usually a shrieking sound, although you may also hear rattling.
When you run your air conditioner, a rattling sound might be heard if your car's drive, or serpentine, belt is starting to wear out. This is because turning on the air conditioner puts greater strain on the belt, exposing any flaws that may be causing it to move unevenly through the pulleys. Examine the belt; if the ribs facing the pulley are missing, or other pieces are missing, or the belt appears broken, it should be replaced.
- Compressor Pulley
Bearings that keep the compressor pulley in place may wear out and cause a ruckus. However, the sound you'll hear is usually a screeching, grinding, or roaring noise, which is not the same as rattling. If you hear rattling, the problem isn't with the pulley.
- Compressor Clutch
Because the compressor is the most important component in the operation of your air conditioner, air conditioner rattle produced by the compressor demands the most complicated repair. The compressor has many moving parts that might wear out over time, resulting in a rattling that can be heard every time it turns on. It's possible that the compressor clutch, rather than the compressor itself, is to blame.
The compressor clutch is another component that is prone to wear. The compressor, which pressurizes and pushes refrigerant through the air conditioning system, is controlled by this clutch. A rattling clutch is one that has been worn out. In this case, replacing both the clutch and the compressor may be necessary to remedy the problem. It may be possible to replace just the clutch rather than the full unit on some vehicles. If you feel this is the issue, you should ask your mechanic if they can be serviced individually.
- Idler Pulley or Power Steering Pulley
When you turn on the air conditioning in your car or truck, it puts extra strain on your motor, which can lead any unconnected pulleys to show their real colors. Unusual air conditioning sounds are frequently caused by an idler pulley or a power-steering pump pulley.
The various engine drive belts that run with your vehicle's engine are guided, connected, and tensioned by idler pulleys. So, while the serpentine belt connecting engine power to the air conditioner may be good, the idler pulley that goes with it may require replacement. High-mileage automobiles will almost certainly require a new pulley, but this is a relatively affordable repair.
After the AC is turned on, the power steering pump pulley may make noises owing to excessive tension, which can be found during your next auto AC repair. If you can't find the source of the noise, it's worth inspecting your vehicle beyond the obvious AC suspects. Car air conditioner clattering can be an annoyance as well as a warning of major harm. Many causes of rattling are simple to fix at home, but if the damage is substantial or involves the compressor, see a mechanic.
- Other causes beyond your air conditioning system.
If problems with the air conditioning system have been ruled out, there are still other components to look into when you observe your car air conditioner clattering.
Once the engine is started, loose parts, such as the hood prop rod, will rattle. Other components of the A/C system could be malfunctioning as well. A rattling sound can also be caused by a faulty condenser or debris on the fan belt or between ac slats.
The culprit could also be found under the hood. When a water pump malfunctions, for example, it usually rattles, which sounds like marbles flung around in a can when the car is idling. Also, a sliding or misaligned camshaft.
When you hear a rattling sound coming from your air conditioner, there are a number of possible causes. To summarize, this sound is not only strange and uncommon. It's a symptom that there's an issue with the A/C system, and it's something to be concerned about. Even if the A/C works perfectly and blows cool air despite the rattling, it will quickly display other signs of difficulty after the rattling sound has been heard for the first time.
Car AC Hissing And Not Cold
The hissing noise is caused by a lack of refrigerant in the A/C evaporator. You'll need to add refrigerant and dye to the system to get rid of the hissing. Then, using a leak dye light (black light), check for leaks and patch them as needed. The hissing noise of the air conditioner is most noticeable when the vehicle is turned off, and it comes from beneath the dash.
Don't worry if the air conditioner is blowing cold air and making a hissing noise; everything is as it should be. If your air conditioner isn't chilling effectively and you hear a hissing noise, you may have a problem with the metering unit.
Many DIYers discover that their air conditioner won't cool after using a DIY kit to add refrigerant. They believe that if they add refrigerant and the can's gauge is green, they should be getting cold air. However, the seal can sometimes be broken, allowing refrigerant to escape. When you have a leak, air enters the system, which can cause major issues.
The system will stop cooling when you reach 6% air, which could cause the evaporator to freeze. You will be adding air to the system if you do not purge the air hose on your DIY recharge kit before connecting to the charging port (the air that was in the hose before you squeezed the trigger). That's why, before recharging, competent shops insist on first detecting and correcting the leak, then pulling a complete vacuum to remove all the air. You're going to have issues if you leave air in the system. So in case you observe continuous hissing sound and the air is not cooling better get professional help.
Car Air Conditioner Hissing Noise When Off
As mentioned, another common sound drivers notice from their car's air conditioner is a hissing noise. The good news is that this isn't always a bad thing. After you turn off your automobile, you may hear the AC hissing. This is your car's way of equalizing pressure.
It's totally common for your car's air conditioner to make a hissing noise. Pressurizing liquid refrigerant and then releasing it through a small aperture is how car air conditioners function. The metering device might be an orifice tube positioned in the engine compartment or an expansion valve located in the passenger area, depending on the type of system utilized by the carmaker. They create a little AC hissing noise as they discharge the high-pressure refrigerant, similar to what you hear when you depress the nozzle on a spray can.
When your air conditioner is turned on, your system has both a high and low pressure side. A refrigerant, such as Freon, circulates between these two sides, which are separated by an expansion valve or an orifice tube.
When you turn off your car, the Freon will migrate from the high-pressure part of your AC compressor to the lower-pressure side to equalize. While AC pump noise is quite typical for your car's air conditioner, hissing at any other point, such a buzzing noise, should prompt you to visit your repair.
Maintain the condition of your car's air conditioning system by inspecting it on a regular basis according to the owner's manual's instructions. This involves checking the cooling fan, cleaning the condenser, and replacing the cabin air filter as needed. Although an unusual sound does not always follow a problem, proactive maintenance can help you avoid problems and future repairs.