Existing HVAC System Upgrade or Expansion Description Guide describing how to upgrade or expand an existing HVAC system.
Outdoor Air Intake Damper Controlled Description No outdoor air intakes connected to return side of the HVAC system, unless controls are installed to operate intermittently & automatically based on a timer and to restrict intake when not in use (e.g., motorized damper)
Whole-House Ventilation Strategies for New Homes Description This guide describes how to install a whole-building ventilation system to provide adequate dilution of indoor air contaminants.