Is it a good idea to insulate the whole-house fan in the winter months?

There are a variety of insulated covers designed specifically for the winterization of whole-house fans.

There are a variety of insulated covers designed specifically for the winterization of whole-house fans. The key function of a whole-house fan is to relieve the buoyant heat from the living space by pulling cooler air through window openings on desirable weather days. When trying to retain heat, an insulation cover is recommended to provide maximum retention. Consider covering the entire unit with paper, foil or plastic backed insulation. Or, build a box out of rigid foam board. The only caveat is disconnecting the power source when it's covered to avoid any possibility of turning it on. Another recommendation would be to disconnect the power and place an insulated blanket over it.