A heat pump is a device that acts as an air conditioner in the summer, by ejecting heat from the inside to the outside; and as an electric furnace in the winter, by drawing heat into a home from outside. Heat pumps act as one unit used both for heating and cooling. Technically speaking, heat pumps are vapor-compression refrigeration systems with both indoor and outdoor coils that act reversibly as condensers or evaporators - depending on if they're needed for heating or cooling. Heat pumps function just like an air conditioner in the summer, and the cost to cool a home. In the winter heat pumps heat the home by pumping warm air into the home. Because heat pumps don't burn fuel, they are considered safer than a gas powered furnaces. Traditional split-system heating systems have two parts - an indoor furnace or air handler and an outdoor heat pump that work together to heat and cool your home.
