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California Indoor Comfort Inc Blog

What a Hissing Noise Means For Your AC

Your home’s air conditioner was designed to be mostly silent. Other than the sound of it turning on and off and the sound of air flowing from the vents, hearing any unusual sounds from your air conditioner is cause for concern.

When you hear loud and obnoxious sounds such as banging, clanging, booming, or grinding, it’s pretty obvious that something is wrong and you’re likely going to see its performance suffer in some way which will prompt you to call for repairs.

However, hissing can be very quiet and intermittent, so it can be easy to miss or even ignore. But hissing can actually be a major problem for your air conditioner. If you hear hissing noises coming from your AC, it may be time for AC repair in Fresno. Keep reading to learn more about the source of your AC’s hissing noises and why they’re potentially dangerous.

Hissing and Bubbling

If you hear hissing that is accompanied by a bubbling sound, this is an indication that you have a refrigerant leak. Your refrigerant is either in a gas or liquid form, depending on where it is in the lines and what the cooling cycle stage is. If you have a refrigerant leak where the chemical is in its gas form, it’ll cause a hissing sound. 

If the leak is in a part of the line where the refrigerant is in its liquid form, it will make a bubbling sound. It’s not unusual for there to be leaks in multiple areas of the line, resulting in both bubbling and hissing noises. If you are losing refrigerant charge, your AC may not be cooling your home efficiently. Not only does the line need to be repaired to prevent leaks, but your refrigerant needs to be recharged, too. 

Compressor Hissing 

If your AC’s outdoor unit is producing a hissing sound, your compressor may be to blame. When the pressure inside your compressor gets too high, you may hear a whistling or even a shrieking sound. This can be very dangerous, so you want to turn your system off right away and call someone from our team to come out and take a look. 

If you let the sound continue, it can do significant damage to your compressor. Since your compressor is one of the largest components inside your air conditioner, it is also one of the most expensive to replace. If your compressor goes out, it’s so costly to replace that sometimes you may be better off replacing the entire unit. That’s why it is so important to catch problems early and repair them before they get worse. 

Intermittent Hissing

If you hear a hissing sound that only lasts for a few seconds and then goes away, that may be completely normal. If your refrigerant is in the expansion valve, it can produce a hissing sound, and is just part of your air conditioner’s operation.

For any concerning noises coming from your air conditioner, don’t ignore them in the hope they’ll go away. You don’t want to end up with a potentially costly repair because the problem was ignored. Contact us today to come take a “listen.”

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