[Heating System] Air Sourced Heat Pump [Cons] In colder climates, less heat energy is available for the heat pump to provide house heat. At temperatures below 45 degrees Fahrenheit (or 7 degrees Celsius), air sourced heat pump systems are not effective. [Pros] 
Easy to connect with a heat recovery ventilation (HRV) system or a central air filtration device. Simple installation. Excellent heat control on a room by room basis. Unused rooms can have the heat set low.