Basics of OvalAir

“OvalAir” is a concept that we’re testing in a variety of spaces and organizations.  It’s a simple principle, based on the observation that many large facilities have hot and cold spaces, a wide range of temperature gradients, and local peaks and valleys, simultaneously.  Sometimes natural air circulation exacerbates the problem, in particular when hot air rises between floors or within a tall space.

The tendency is to try to heat the cold spaces and cool the hot spaces with additional HVAC equipment and more complicated ductwork, requiring more energy and excess capacity.  The goal of oval air is to find inexpensive ways to mix the air intelligently throughout the facility, balancing the hot and cold spaces with little or no energy and equipment.  We try to set up an oval pattern of continuous slow gentle air flow within the space, and between spaces.  Ideally, people using the space don’t notice the flow, or feel it only slightly.

(Eliminating ductwork through oval air might have a variety of benefits.)

We determine the need for mixing by visiting at different times, asking questions and using our own “heat sense” or an inexpensive laser thermometer (actually an infrared thermometer with laser sighting).

OvalAir can be as simple as keeping a door open between spaces, or closing it between floors.  If the different air columns are not mixing naturally, we can add small inexpensive fans (purchased off-the-shelf from a consumer outlet) to encourage mixing.  We’ve been experimenting with fans in auditoriums, at the back of large church spaces, between the classrooms of a school, etc.  In some cases we’ve used fans blowing into the overhead space above a drop ceiling to mix air across a large but low space.

The object is not to blow air directly onto people, but to mix air slowly but continuously, so that hot and cold areas don’t happen.  The fans are always pointed away from people, and operate as slowly as possible.  We’ve put them in corners pointing up, for example, to make sure they don’t create a direct draft, or set them high in a space and pointed across the ceiling.