Abstract: A system for transferring ambient air from an interior of a house to a pet enclosure external of the house, thus allowing for the pet enclosure to receive cooled or heated air approximating the temperature of the house. An electric fan housed in a preformed enclosure is installable in, or on, the house exterior wall. An air conduit between the fan and pet enclosure is preferably provided by a flexible rubber transfer duct which may vary in length. Conduit connections at the house and at the pet enclosure use a gasket/flange sealing system. A damper to avoid backflow of air is provided near the fan. And a protective cover at the pet enclosure limits access from the pet enclosure to the conduit. An end cap to protect the house when the duct is not in use is also shown.