Tradewindsâ„¢ Compact120 and Tradewindsâ„¢ Compact120D heat recovery ventilators were specifically designed for applications such as high-rise condos, hotels, and apartments. The Compact120D offers a ventilation range of 97 cfm to 143 cfm; the Compact120 has a ventilation range of 89 cfm to 120 cfm. Both units have a thermally conductive aluminum core, an independent motorized impeller for each airstream, and three-speed operation. The cross-flow heat recovery core transfers heat between the exhaust and supply airstreams. The Compact120D has an automatic damper defrost with adjustable defrost times, whereas the Compact120 has a fan defrost system. Unit features include washable air filters in the exhaust, 120 VAC, supply airstreams, and 5-inch duct connections.