Heat pumps are a multi-faceted system and can do the work of an air conditioner and heater.  The standard role of the heat pump is to pull heat from one location to another without using a lot of energy.  Heat pumps generally pull heat out of the air or ground and warm an area or it can be reversed to cool the space.  A heat pump and air conditioner work in very similar ways. If you install a heat pump, there is no need to install a separate system for heating and cooling. Heat pumps are also extremely efficient because they do not burn fuel for heat they simply transfer heat from one location to another.