Spring & Fall Are Perfect For Economizers



     An added benefit of working economizers is that they bring “Free” Cooling into the building during Spring & Fall, when outdoor air conditions allow.  By utilizing cool ouside air, the system does not need to mechanically cool the air before circulating in the indoor space (provided temperature and humidity is within desired system range). 

     While “Free” Cooling is an added benefit during Spring and Fall, economizers are useful 365 days per year.  They can always be used year round to bring in a desired, predetermined percentage of fresh outside air into the building’s occupied indoor space. 

     And fresh outside air is not only a critical component for combating COVID19, it also provides general benefits to building occupants overall health and productivity.



Fresh Air Ventilation’s Critical Role vs COVID19



     Enhancing Indoor Air Quality within buildings has been recommended by ASHRAE and government agencies as an effective method to combat COVID19 within occupied indoor spaces.  The two easiest ways to accomplish this are through Filtration & Dilution:

  • Filtration: Upgrading Air Filters to use MERV13 rated filter media
  • Dilution: Increasing Ventilation and introducing more Fresh Air into the Building

.    In this email, we will focus on Building Ventilation / Dilution and its associated benefits.  Building Ventilation utilizes the Economizers in an HVAC system to introduce more fresh air to be pulled into the building. 


     This new introduction of fresh air dilutes the existing indoor air in the building space, thereby reducing the concentration of any existing airborne contaminants. 


     In order to take advantage of these Ventilation benefits, we must first verify the following:

  • Not all systems have economizers.  Your building’s HVAC system must first have economizers installed
  • Economizers must be verified to be in working order and functioning properly
  • System may need to be air balanced
  • We need to be able to prove how much fresh air is being brought in to the system/building 
Economizers bring fresh outside air into the building, which dilutes the existing indoor air in the building space, thereby reducing the concentration of any existing airborne contaminants.  

      If your equipment has economizers, now is the time to make sure they are fully operational so that you can take advantage of the benefits listed above.



How Economizers Work



As the diagram to the right shows, economizers bring a predetermined percentage of outside air into a building. Instead of being re-circulated, the return air from a space is directed outside and this new outside air is brought in. Depending on the economizer’s settings, the economizer will mix the desired amount of fresh air with the return air before returning it to the indoor space.