Is your Car AC Making Hissing Noise? Do you want to know why it is happening and to fix it? If the answer is yes, then read this article.
Have you noticed that your car’s air conditioning system is making weird, hissing noises? If you find it, please do not ignore it, as it is a warning sign that something is wrong. Car A/Cs are a crucial component of the vehicle and are prone to problems compared to other parts. One of the symptoms that indicate that something is wrong with your car’s a/c is a hissing sound.
This blog will discuss why your car’s a/c is making hissing noises. We will also discuss the probable reasons why this happens, as well as go through the procedures of how you can fix this issue.
How Do I Fix the Hissing Noise in My Car AC?
If you want to fix the hissing noise that your car is making and need help fixing, then worry not because we will discuss its solutions. Each of the problems has a different level of severity. Hence the method of fixing it will depend on that. For some of them, you must take the help of a professional car mechanic shop.
Schrader valves are generally used in many compressed gas and pressurized liquid applications, for example, grill cylinders. If you notice your Schrader valve leaking, you must change it immediately. Changing a Schrader valve does not require the help of a professional if you know the basics of car mechanics.
To determine if you need to change it, look at the Shrader valve’s cap. If you see excess oil or freon bubbles in it, it means it needs to be changed. To replace it, first, remove the Schrader valve from the low-pressure line. For this, you will need a stem valve remover. Next, insert the new Schrader valve, ensuring there isn’t any air in the system. Next, charge the air conditioning unit till it reaches the necessary PSI. Once that is done, check if the air vent is giving out cool air.
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Problems With The Compressor:
Another reason your car’s air conditioner is making hissing noises is that it has become defective due to high pressure. If your car’s a/c makes a hissing sound during acceleration, the clutch or idler pulley has become faulty. Repairing the a/c compressor could be heavy on your pocket, and it is usually cheaper to just replace the air conditioner, all you have to do is contact a car ac mechanic. If the hissing sounds continue for an extended period, then you must consult a car ac technician as soon as possible.
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Leaking Of The Refrigerant:
During the investigation, if you see leaks in the condenser or evaporator, it means that gaseous escapes could be the real problem. To fix it, you will need to repair the defective unit entirely, check for cracks, and crimp it; however, if you see bigger holes, you must seek professional help. However, if there are leaks in the refrigerant line, you can repair it using an a/c repair seal. This way, it is going t be pretty cheap. Your coils also use a/c repair seals on the metal components of your a/c.
Why Does My AC Make a Hissing Noise?
As we discussed above, there could be various reasons your a/c is making hissing noises. If you notice your a/c system is making noise, you shouldn’t overlook it. If your car’s a/c hisses in intervals, it could indicate refrigerant leakage. A refrigerant is a chemical found in a gaseous state in your air conditioner to remove heat from the environmental air.
It helps to give in cool air in the cabin. If your car’s air conditioner seems to hiss, it usually indicates a refrigerant leak in the system. If it is the internal valves, that could affect the functioning of the compressor. When you discover hissing sounds from the a/c, you must call for professional help in these cases. Aside from that, screeching or sounds accompanying the hissing are signs of a defective compressor.
The hissing you hear when the air conditioner is on could be due to a malfunctioning A/c clutch. If you continue using your faulty a/c compressor, it could cause heavy damage in the future. The repair charges will also be huge in this case. So if you face such issues in the middle of riding, you must immediately go to the closest available HVAC mechanic.
Can Low Freon Cause a Hissing Noise?
Is freon a new term for you? Freon is nothing but the chemical or refrigerant used to provide cool air in your car. Without the presence of freon, the cold air won’t be able to circulate in your car’s cabin. When the freon levels become low, the vehicle’s A/C unit won’t function as it is supposed to. The clutch of the A/C wouldn’t be able to engage because the freons’ level is too low for the compressor to pressurize. Hence, freon is crucial for your a/c’s system to function correctly.
In its liquid form, Freon evaporates in the expansion valve and is then converted to cold gas. Then it moves through coils in the system, which are supposed to absorb the heat in the car, thus making your cabin turn cool. If you notice leaks that seem like light grease, then it probably means that the freon levels are low.
When you have a sight glass in your vehicle, you can also check the freon levels on that. If the levels are proper, a clear liquid will flow through the line. However if the levels are lower than they should be, you will notice bubbles. If there isn’t any movement, this indicates there is no freon in your car.
Also Read: Top 7 Reasons Why Your Car AC is Not Blowing Cold Air
Why Does My Car AC Make a Hissing Noise When I Turn it Off?
A lot of times, when your car is off, you would hear a hissing sound. Thankfully, there isn’t much to worry about as this is not harmful to your car. The hissing sound you hear when your car’s A/c is off is due to the car’s equalizing pressure. It happens because your car’s A/c unit has two sides, one of them being the low-pressure side and one of them being the high-pressure side.
The refrigerant usually moves through the tubes and valves from each side. When you turn off your car, the refrigerant needs to equalize. The hissing noise that you hear is the sound of the transfer of excess gas from one side to another side. The A/C system’s refrigerant is under continuous pressure. When it depressurizes, it tends to make hissing noises.
Is AC Supposed to Hiss?
Just like any other machine, there is a possibility of your’ a/c malfunctioning for some reason. Hissing noises from the air conditioning system can indicate an issue. However, it does not always indicate danger. A lot of times, hissing can be completely normal. A valve in the a/c called the thermostat valve is responsible for relieving pressure from the refrigerant.
These hissing noises are not exaggerated at all and are, in fact, very quiet. If you hear this noise in intervals, then it means there isn’t anything serious. But if you hear the noises continuously or notice changes in it while it transitions, then you should seek professional help.
Why is My AC Making Noise All of a Sudden?
Your car air conditioner can make several noises, each indicative of different reasons.
- If you hear hissing sounds for a few seconds, then there is no reason to worry. It could be the gas in the valves. However, if the sounds continue for a while, it could mean a refrigerant leak.
- If you notice buzzing sounds, then it probably means that there is an issue with some of the air conditioner’s components.
- If you hear grinding noises, it could either mean that the inner belts are damaged, or there are issues with the A/c’s compressor. Usually, the a/cs compressor makes grinding noises because of the pistons that are supposed to compress the refrigerant gas. In such cases, the solution is to replace the whole a/c unit.
Conclusion:
So that’s it for today’s blog on Car AC Making Hissing Noise.
With this, we conclude our blog that discusses why your car could be making a hissing noise and possible solutions to fix it.
We also want to remind you that if your car’s a/c starts to hiss unexpectedly, and if you’re not sure about the reason and how you can fix it, you should seriously consider taking professional help.
The chemicals present in the gases of the air conditioner can be hazardous to your health, and there are no specific antidotes to cut off the poison. Also, if you want your car’s a/c to continue to function correctly, then you should make sure that the freon levels are optimal.
For any assistance, contact a professional to fix the issue at the earliest.
Related Post: Car Ac Compressor Squealing: Reasons and How to Fix It
FAQ’s
Q1. Why Does My Car AC Make a Hissing Noise When Turned on?
A hissing sound from the car’s AC often indicates refrigerant pressure equalization, which is normal during operation. However, if the sound persists, it could be due to refrigerant leaks, a failing expansion valve, or other mechanical issues in the AC system.
Q2. What Does a Hissing Sound From the Dashboard Mean?
A hissing noise near the dashboard typically comes from the evaporator, suggesting refrigerant leaks or air entering the system.
Q3. Is a Hissing Noise From The AC a Sign of a Refrigerant Leak?
Yes, a persistent hissing sound may point to a refrigerant leak in components like hoses, connections, or the compressor.
Q4. Can I Drive My Car if The AC is Hissing?
While driving is possible, ignoring the issue can worsen the problem, especially if it involves refrigerant leaks or component damage. Prompt inspection is recommended.
Q5. How do I fix a hissing car AC?
Diagnosing the issue involves checking refrigerant levels, inspecting components for damage, and cleaning or repairing parts like the expansion valve or compressor. Professional assistance is often necessary to ensure proper handling of refrigerants and repairs
