Fresh Air Return

Adding fresh air to a heating or cooling system accomplishes two primary indoor air quality goals. It pressurizes a building and increases indoor air quality by diluting polluted or stale indoor air. Adding a fresh air inlet to most systems is typically a simple and relatively inexpensive proposition.

The addition of fresh air into the building has several other benefits. As it pressurizes the building, some air is exhausted out of the building. This dilutes the existing air with fresh air, and forces a percentage of the indoor pollutants out of the building with each air change.

Ventilation codes and standards, including ASHRAE 62.2-2003 standard, Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings.