AC Unit Blowing White Mist? Here’s What It Is

A white air conditioner with smoke coming out of it.

Seeing a white mist seeping from your AC unit can be quite alarming. Initially, you may wonder if it's smoke. However, this mist doesn’t smell like smoke – and your AC seems to be working fine. So, what is this mystery mist and should you be concerned? 


It’s Not Mist – but Tiny Water Droplet


What you're actually seeing is condensation coming from your unit. Condensation (or mist) occurs when humid air flows over the cold evaporator coil. This sudden change in temperature causes the moisture in the air to condense, forming tiny water droplets.


Similarly to how fog works, these tiny water droplets suspend themselves in the air, appearing as mist. While it can be alarming, it is not uncommon, especially in the southeast where humidity is high. 


Is This Something To Be Concerned About?


No, not typically. Condensation is a naturally occurring process and the occasional mist coming from your AC unit shouldn’t cause concern. However, you should be concerned if:

  • The mist continues for prolonged periods
  • You notice a musty smell
  • Your AC unit isn’t working properly


Issues like these could indicate that your AC has a clogged filter, blocked drain or refrigerant leak. These problems should be addressed by a professional HVAC technician quickly as they can lead to decreased AC efficiency, higher energy bills and damage to either the unit itself or the surrounding areas.


What Should You Be on the Lookout For?


While condensation is typically normal, there are other signs of malfunction that homeowners should be on the lookout for. These include:

  • Weak or warm airflow – This could indicate a problem with the compressor, ductwork or a clogged air filter. It’s a sign your system isn’t cooling properly and should be inspected. 
  • Unusual noises – Loud noises coming from your AC (like banging or clanking) could indicate that parts are loose, there's a problem with the compressor or the bearings are suffering from wear and tear. 
  • Musty smells – A mildewy smell could mean that mold or mildew growth may be present. This can occur if lots of moisture is present, which oftentimes results from an underlying problem with your AC unit. 
  • High humidity – If your home is very humid, it could be a sign that your AC is having a hard time removing moisture from the air.
  • Increased energy bills – Higher energy bills are a clear indication that your AC unit is not working properly. 
  • Inconsistent temperatures – Inconsistent temperatures throughout could be the result of a malfunctioning AC, especially if this hasn’t been an issue in the past. 
  • AC unit keeps turning on and off – Also known as short cycling, this happens when your unit’s safety mechanism is activated. These mechanisms force the AC unit to shut off to avoid damage. Typically, the safety feature is activated if your unit is overheating. So, if your unit is frequently shutting on and off, it could be a symptom of a bigger problem. 
  • Water leaks – Water leaking around your AC unit often signals that there's something wrong. This could be a clogged drain line or a refrigerant issue. 


When It’s Time To Contact an HVAC Professional


If your AC is experiencing any of the following issues, it’s important to contact an HVAC professional right away to diagnose and fix the issue. If left untreated a small repair could turn into a costly project. 


Plus, you shouldn’t try to attempt a complex repair on your own. Doing repairs on your own can lead to bigger problems or even injury. A certified technician is equipped with the tools and knowledge to quickly address and fix problems before they escalate. 


Need Expert HVAC Technicians? Call Us Today!


If you need professional HVAC services, don’t wait! Call C & G Heating & Air Conditioning today for issues regarding your AC unit. Located in Smiths Station, we serve several communities along the Alabama-Georgia border including Phenix City, Auburn, Opelika and Columbus.


Our team of experienced HVAC technicians can help answer any questions or concerns about your HVAC system, all while performing top-of-the-line maintenance. For more information, give us a call at 334-489-3329. To learn more about other services, visit our website by clicking the link here. 


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