rooftop hvac with economizer

What is an Economizer and How Can it Benefit My Commercial HVAC Unit?

If you’re a property manager, building owner or facilities manager for a commercial business, you’re likely interested in saving money on cooling your commercial building. The fact is, many commercial building owners are simply paying too much for their utility bill because they’re unaware of modern solutions. One lesser-known element of an HVAC system that can make a huge difference for your energy costs is an HVAC economizer.

You may be thinking that an “economizer” for a HVAC certainly sounds like a good idea, especially in San Antonio and other Central Texas areas where utility bills can cause quite a hit to the bottom line for a business. So, what is an economizer and how might it benefit your commercial facility?

What is an economizer?

An economizer is a part of the outdoor system, most often mounted on the roof, of an HVAC system for commercial buildings. The economizer evaluates outside air temperature and even humidity levels. When the exterior air levels are appropriate, it uses the outside air to cool your building. HVAC economizers use logic controllers and sensors to get an accurate read on outside air quality. As the economizer detects the right level of outside air to bring in, it utilizes internal dampers to control the amount of air that gets pulled in, recirculated and exhausted from your building. 

Why is an economizer a good idea for my commercial property?

HVAC economizers have a variety of benefits that may just make them the best kept secret in the commercial HVAC world. In fact, we call economizers “free cooling” in the industry. Here’s why we recommend economizers for our commercial HVAC customers.

  1. Economizers lower energy consumption, meaning lower energy costs. Instead of relying on your property’s A/C unit to constantly cool, you can utilize the outside air to do that job for you. The less your A/C unit runs, the lower your utility bill. 
  2. Economizers reduce the amount of work your A/C unit does, prolonging the life of your system. In addition to helping reduce costs, that decrease in wear and tear on your HVAC system means less maintenance, fewer breakdowns and overall, a longer lifespan for your system.
  3. Economizers improve indoor air quality through increased ventilation. Many buildings, especially older ones, weren’t designed with modern ventilation in mind. An economizer can improve air quality by bringing in fresh air and exhausting your building’s stale air. An academic study published by the University of North Texas estimated that economizers provided savings of up to $16,000 annually thanks to reduced sick days from air pollutants.

What are the different types of economizers and how do they work?

There are various types of economizers available based on a building’s needs and varying budget requirements. 

  • Dry bulb – This is the simplest type of economizer. It uses a sensor to evaluate the difference between the interior temperature and outdoor air. Unfortunately, a dry bulb economizer is not a good choice for San Antonio given our humidity. Dry bulb economizers are only effective in arid climates.
  • Single enthalpy (Wet Bulb) – This economizer is more advanced than the dry bulb economizer. It evaluates air temperature as well as humidity and is used by the majority of HVAC systems. A single enthalpy economizer makes up the vast majority of what we recommend and install for commercial buildings in central Texas.
  • Differential Enthalpy – Even more advanced, this economizer uses two or more sensors to measure the return air as well as the outside air. We would expect to see this option in more complex scenarios, where, for example, a single, large system is sending air to anywhere from five to twenty zones through secondary air handlers.

How do I know if I have an economizer?

As a facility owner or property manager, it can be hard to know if you have an economizer or whether it’s working exactly as it should. Don’t continue paying more than you need to in order to keep your property comfortable. Give the friendly experts at North East Air Conditioning a call to learn more about how an economizer can help you save money, expand your HVAC unit’s lifespan, and improve your indoor air quality.


Call: 210-658-0111