“D” Series energy recovery ventilators are utilized in applications that require a
rooftop installation. These units may be installed as a stand-alone unit with a
separate and distinct duct system from other air conditioning equipment. In many
applications the supply (intake) air duct is connected to the return air duct of an air
conditioning system (or multiple systems). By doing this the enthalpy wheel is able
to provide preconditioned outside air to the air conditioning system(s).