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A commercial HVAC system that is properly designed & installed as well as professionally maintained should provide years of reliable service. As a matter of fact, an HVAC system that is functioning well should be unnoticeable. It should create a comfortable, clean indoor environment with air that is constantly circulated, purified, and either heated or cooled depending on the season. Sometimes though, an HVAC system might not work as well as it should. There could be a few reasons for this, including mechanical failure, air blockage, or a thermostat malfunction. One of the most obvious ways to identify a problem, though, is by noticing any unusual odors coming from the HVAC system.

The Four Most Common Commercial HVAC Odors and Their Solutions:

  1. Burning
  2. A burning odor from an otherwise well-functioning HVAC system could be indicative of a few things. A primary cause is usually an old or clogged filter. In this case, a fix could be as simple as replacing the filters with new ones or having your local commercial HVAC company perform this task. A secondary cause of a burning odor could be that the HVAC system is overheating. It would be important, then, to have a professional evaluate the system for mechanical efficiency and functionality.

  3. Raw Sewage
  4. The primary function of a commercial HVAC is to move large volumes of air throughout a building. The odor of raw sewage almost always has nothing to do with an HVAC system, and is usually caused by faulty plumbing. However, since the HVAC system transports air to and from different parts of a building, it can sometimes transport unpleasant smells as well. It would be important to have this odor diagnosed and fixed by a plumbing professional.

  5. Rotten Egg
  6. Similar to a raw sewage odor, a rotten egg odor almost always has nothing to do with the commercial HVAC system, but can be associated with it nonetheless. The smell of rotten eggs is usually indicative of a natural gas leak, which is a separate problem that should be professionally diagnosed.

  7. Oil or Exhaust

    An odor that smells oily or like exhaust usually means that there might be some type of mechanical issue with an HVAC system. These systems are machines, after all, and over time there could be fittings that come loose or leaks that develop. If this odor is experienced, a visit from a commercial HVAC company is highly recommended.

Unusual odors may be annoying and can cause quite a stench in an office building, but they’re only one of the 7 Signs It’s Time to Replace Your Commercial HVAC Equipment.

If you notice any of the listed odors coming from your building’s HVAC system, especially any burning smells, oil or exhaust fumes, get in touch with the seasoned professionals at Donnelly Mechanical.

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