Why Is My AC Making a Hissing Noise

A hissing noise inside your HVAC system is not something to be disregarded. Among the possible causes are leaking refrigerant lines, an internal valve leak or a serious problem with your compressor. If the hissing noise is heard from your ducts, then you may have leaking air ducts. This is annoying, but not necessarily a cause for alarm. A hissing sound may indicate any of these things, but we’ll try to narrow it down a little more.

Does the Hissing Sound Stop After a Few Seconds?

If you hear a hissing noise that ends after a few moments, you may not have any problems. That can be refrigerant in your expansion valve, which is part of the normal day-to-day operation of your HVAC system.

Is the AC Making a Hissing Sound With Bubbling Noises?

Are you hearing a bubbling sound paired with a hissing sound? This can indicate a refrigerant leak. If a refrigerant leak is present, you might notice a slight hissing sound as the refrigerant escapes via the leak. Refrigerant escapes as a gas and can be a serious health concern. If you have signs of a refrigerant leak, turn off the unit and call a qualified HVAC company to come inspect the system.

If the issue is a valve leak, it should be repaired by a qualified technician as soon as possible. The job of the valves is to regulate the pressurization of the refrigerant gas and left alone, the leak will worsen. When it does, the hissing sound will often intensify, which can be a tell if you’re looking for a cause. You must maintain adequate pressure in your system for it operate correctly, and leaks create additional health and maintenance problems. You ought to get this fixed post haste if possible.

Are Hissing Noises Coming From the Compressor?

The compressor is located in the exterior air conditioning unit, which is also called a condenser unit. Listen around here for the hissing noise. If it turns out that the compressor is the issue, this could be a dangerous situation because it is an indication that the pressure within the compressor is too high. If you hear hissing, whistling, or shrieking coming from your compressor, shut off your air conditioner pronto and call a professional technician.

Compressors are some of the most pricey units to repair or replace inside an AC unit. Compressors are the part responsible for cycling refrigerant through the system. You cannot turn on an air conditioner and cool your home without a compressor. The pricing varies based on factors such as the type, unit size, and brand requirements. If you have a two stage compressor in the unit today, you will need to replace it with a two stage compressor. It’s impossible to upgrade or downgrade the compressor type – your unit has specific requirements for what compressors are installed and won't accept substitutes. While it’s impossible to say how much a compressor replacement is because of the variable costs, the bill is frequently high enough to just do a replacement in older units. This is why it’s crucial to shut off the air conditioning and call a trustworthy HVAC company if you hear hissing sounds coming from the compressor.