Why is my AC making a hissing noise? 

A hissing noise coming from your HVAC system is not something to be overlooked. Among the possible causes are leaky refrigerant lines, an internal valve leak or a serious problem with your compressor. If the hissing noise is originating from your ductwork, then you could 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 further. 

Does the hissing sound end after a few seconds? 

If you hear a hissing noise that ceases 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 may indicate a refrigerant leak. If a refrigerant leak develops, you might notice a light hissing sound as the refrigerant escapes from the leak. The coolant escapes as a gas and can be a major health concern. If you notice signs of a refrigerant leak, shut down the unit and call a expert HVAC company to come evaluate the noise. 

If the problem is a valve leak, it should be repaired by a qualified technician as soon as possible. The job of the valves is to help with 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 sign if you’re looking for a cause. You need to maintain adequate pressure in your HVAC system for it operate correctly, and leaks create additional health and mechanical problems. It’s best to get this fixed quickly if possible. 

Are Hissing Noises Coming from the Compressor? 

The compressor can be found in the exterior air conditioning unit, which is also called a condenser unit. Listen nearby the condenser for the hissing noise. If it turns out that the compressor is the cause, this could be an unsafe situation because it is an indication that the pressure inside the compressor is too high. If you hear hissing, whistling, or shrieking coming from your compressor, shut off your air conditioner without delay and call a professional technician. 

Compressors are some of the most expensive parts to repair or replace inside an AC. Compressors are the part responsible for circulating refrigerant through the system. You cannot power on an HVAC system and cool your home sans compressor. The expense varies based on factors like the type, unit size, and brand requirements. If you have a two stage compressor now, you would need to replace it with a two stage compressor. It’s not possible to upgrade or downgrade the compressor type – your unit has specific requirements for what compressors are installed and can’t be MacGyvered. While it’s impossible to give a quote online because of the variable costs, the bill is frequently high enough to think about a replacement in older air conditioners. This is why it’s crucial to shut off the air conditioning and call a reliable HVAC company if you hear hissing sounds coming from the compressor.