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What Does That Hissing Noise from My AC Mean?

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What Does That Hissing Noise from My AC Mean?

Hissing isn’t a good sound in many situations, and this holds true for your air conditioner. There are different levels of hissing, as we’ll explain here, but the bottom line is that hissing isn’t a sound you want to ignore, especially with summer just around the corner.

So what does a hissing sound mean? It can mean a few things, but no matter what the exact problem, it’s important to have your Dynamic Mechanical Heating & Air Conditioning expert manage your air conditioning repair services in the Bristol and in New Haven whenever you hear a hissing sound coming from your AC.

Reason #1: Leaky Refrigerant Lines

The refrigerant in your system is under pressure; as such, if a leak develops, you may hear a light hissing sound as the refrigerant escapes through the leak. Sometimes these kinds of leaks can also be accompanied by a bubbling sound for the same reason.

Reason #2: Internal Valve Leak

The compressor has a valve that, when leaking, can create a small hissing noise. Valve leaks need to be fixed as soon as possible, as these valves help with the pressurization of the refrigerant gas. Left unrepaired, a valve leak will get worse and its sound along with it.

Reason #3: The Compressor

The compressor hissing or shrieking is a serious situation: it means the pressure inside the compressor is too high. If you hear hissing, or worse, shrieking, coming from your compressor, turn off your air conditioner immediately and call a technician; do not restart your air conditioner until it has been looked at by a professional.

When Hissing Isn’t a Problem

Your air conditioner has normal operational sounds, one of which may be short, small hiss noises. One part known for emitting regular hiss sounds is the expansion valve. As the refrigerant gas expands in this valve, it can make a hissing noise that lasts for several seconds and then goes away.

A second place you may hear a hissing sound is in the ductwork at the start of a new cycle. You may want to open your registers more if the sound is bothersome, but you most likely will not have a mechanical issue with which to be concerned when hearing this noise coming through the register.

Don’t Let That Hiss Go

Whether it’s a hiss, a pop or a crackle, unknown sounds in your air conditioner should always be inspected by a professional. For expert air conditioning service in New Haven contact Dynamic Mechanical today!

Tags: Air Conditioning Repair

May 30, 2014 | Categories: Air Conditioning Service

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