Why is my AC making a hissing noise? 

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

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 issues. That can be refrigerant in your expansion valve, which is a part of the normal day to day operation of your HVAC unit. 

Is the AC Making a Hissing Sound with Bubbling Noises? 

Are you hearing a bubbling sound paired with a hissing sound? This could indicate a refrigerant leak. If a refrigerant leak is present, you may notice a slight hissing sound as the refrigerant escapes through the leak. The coolant escapes as a gas and can be a serious health concern. If you notice signs of a refrigerant leak, power down your HVAC and call a qualified HVAC company to come evaluate the noise. 

If the cause 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 sometimes grow louder, which can be a sign if you’re looking for a cause. You need to maintain adequate pressure in your HVAC system for it cool your home, and refrigerant leaks cause additional health and mechanical problems. It’s best to get this fixed post haste if possible. 

Are Hissing Noises Coming from the Compressor? 

The compressor is located in the outdoor air conditioning unit, which is also known as a condenser. Listen around here for the hissing noise. If the compressor is the issue, this could be an unsafe situation because it is a signal that the pressure inside the compressor is too great. If you hear hissing, whistling, or shrieking coming from your compressor, turn off your air conditioner pronto and call an expert technician. 

Compressors are some of the most expensive parts to repair or replace inside an AC. Compressors are the part responsible for cycling refrigerant through the system. You cannot turn on an air conditioner and cool your home sans compressor. The pricing varies based on factors like 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 another two stage compressor. It’s not possible to upgrade or downgrade the compressor type – your unit has specific requirements for what parts 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 big enough to just do a replacement in older air conditioners. This is why it’s so important to shut off the air conditioning and call a reliable HVAC company if you hear hissing sounds coming from the compressor.