What is a unit that provides heating or cooling for a building called?

A unit that provides both heating and cooling for a building is known as a heat pump. Heat pumps are versatile systems that can transfer heat from one place to another, allowing them to both heat and cool indoor spaces efficiently.

When operating in heating mode, a heat pump extracts heat from the outdoor air (even in cold weather) and transfers it inside. Conversely, in cooling mode, it removes heat from the indoor air and releases it outside, effectively cooling the building.

While other options such as an air conditioner, a furnace, and a boiler are related to climate control, they each serve specific functions. An air conditioner primarily provides cooling, a furnace is designed for heating, and a boiler heats water or steam for space heating. However, these units do not offer the dual functionality of heating and cooling that a heat pump provides. This makes the heat pump the correct answer for a unit that serves both purposes within a building.