Rev. December 19, 2008 Page 3 of 191. HOW THE NU-AIR SYSTEM WORKSA. Powerful, centrifugalblowers bring fresh air intoyour home while an equalamount of stale, humid air isexhausted to the outside.This is NU-AIR’s balancedcentral ventilation system.B. Incoming fresh air is filteredbefore flowing through theheat exchange core.C. Stale, humid air flowsthrough the cross-flow heatexchanger and transfers theheat to the incoming freshair.D. Warm fresh air is distributed to each room of the house through an independent ductwork system.2. INSTALLATION2.1. Installer's ResponsibilitiesInstallers are responsible for the performance of the ventilation system and for ensuring that all codesand standards are met. Do not mount the fresh air supply near a source of contaminated air such as automotive exhaust, gasor propane exhaust or oil tanks. Do not hook a dryer exhaust to an HRV. Combustion appliances such as furnaces and hot water heaters must not draw combustion air directlyfrom an HRV. Do not connect a range hood to any part of this system. Do not install in attics or other unconditioned spaces (min. 16º C). Do not install in enclosed garages.2.2. Installation System OptionsBefore installing your HRV, please read theseinstructions for correct installation. The Nu-Air HRVis a self-contained system that is ready to be installed.There are three commonly used and approvedmethods of installation.2.2.1. The Fully Ducted SystemThis system uses an independent duct system forsupply and exhaust air. The HRV is controlledindependently of all other equipment.The best results are achieved when: