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What’s That Sound My HVAC System Is Making?

Whats-that-soundWhen it comes to strange noises your air conditioner can be the source of a number of them.  Some are a result of normal operation; others are indications of more serious potential problems with your AC system.

Never ignore weird noises hoping that they will go away because they normally won’t.  Some noises are normal and do not indicate any imminent problems.  Other sounds, though, can be a precursor to equipment malfunctions that can cause severe damage.

Normal Air Conditioner Sounds
Most AC compressors make some noise when they startup.  If the noises last for just a short time your system is probably running normally.

  • Buzzing: a slight buzzing noise is a common sound that can come from your outdoor unit, even when it is not on.
  • Wooshing: is a common, normal sound that only lasts for a few seconds.
  • Squeals: brief high-pitched sounds heard during the startup of your HVAC system are normal.

Annual maintenance can prevent many of those strange noises from occurring.

Not So Normal AC Sounds
If you hear any of these noises it is recommended that you call an HVAC technician to address the problem before serious system damage occurs.

  • Whining or screeching: worn belts or a failing motor could be the culprit.
  • Rattling: loose hardware may require tightening or replacement.
  • Thudding or clanking: a large component such as a fan blade may be loose, requiring repair.
  • Squeaking: bearings may need replaced.
  • Gurgling or humming: there could be an issue with the level of refrigerant in the refrigerant lines.
  • Hissing: a refrigerant leak could reduce the ability of your system to cool.
  • Vibration: noises caused by excessive vibration could be due to loose parts or refrigerant piping being strapped too tight.
  • Clicking: a clicking sound within your condenser, can indicate debris is trapped inside and contacting the fan blade.

How to avoid hearing these noises
Annual air conditioner maintenance is the best way to address these potentially problematic noises before they turn into big problems.  When you do detect an unusual sound, if you cannot fix it yourself, call a local HVAC professional right away.

Need Service?
If you determine that service on your air conditioner is required, give Mecko’s Heating & Cooling a call at 765-447-7555, we’ll be happy to check out those “strange” sounds you hear.



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Contact Info

  • 765-447-7555 phone
  • 765-448-2988 fax
  • P.O. Box 4982
  • Lafayette, IN
  • 47903

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Contact Info

  • 765-447-7555 phone
  • 765-448-2988 fax
  • P.O. Box 4982
  • Lafayette, IN
  • 47903