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What Does That Hissing Sound From My Air Conditioner Mean?

One of the best ways to tell that an AC system needs help is to really listen to it. Air conditioners don’t yet come with computerized systems that analyze malfunctions and report to homeowners with a full diagnostic on the problem and how to address it. (Well, not yet, at least. Somewhere, somebody in a secret lab must be working on this.)

But air conditioners do provide strange sounds that can warn you when something isn’t right. Call HVAC professionals and let them handle the diagnostic as well as the solution.

A Hissing Air Conditioner

A continuous hissing that sounds like gas escaping from the AC is usually a warning noise. It could indicate several different issues, such as:

  • Refrigerant leaks: Escaping gas might be the actual problem. Leaks along copper refrigerant lines will allow gaseous refrigerant under high pressure to escape, which is a major problem. When an air conditioner loses its refrigerant charge, it can damage the compressor, putting the entire unit in jeopardy.
  • Internal valve leak: The compressor valve can start to leak, causing a hissing sound. This valve controls the pressurization of the refrigerant, so this needs to be repaired ASAP.
  • Compressor problems: It could be that the compressor itself is malfunctioning because the pressure inside it is too high. The compressor is the most expensive part of an AC to repair, and usually, it’s more cost-effective to simply replace the air conditioning system. If the hissing turns into a shrieking noise, shut down the AC and call our repair team right away.

If you only hear periodic hissing sounds that last for several seconds, it’s likely just the expansion valve, which isn’t a problem. However, if the sound is sustained, you need to have HVAC technicians on the job to determine what’s wrong and how to fix it.

Raleigh Heating & Air can take care of all your air conditioning repair needs in Durham, NC, and throughout Wake County.

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