The Hi-Performance Hideaway with Plenum (HPY) fan coil unit provides the same basic features as the HHY plus a return air plenum. HPY units are shipped from the factory ready for installation with the plenum section in place. No field fabrication is required. HPY units are designed with interchangeable panels so that the unit may be modified on site to accommodate a rear or bottom return. Standard HPY units are provided with a galvanized finish.