What is the primary difference between AC (Air Conditioning) and HP (Heat Pump)?

The primary difference between air conditioning (AC) systems and heat pumps (HP) lies in their function and versatility. AC systems are specifically designed to cool indoor spaces by removing heat from the air inside and transferring it outside. In contrast, heat pumps serve a dual purpose; they can both cool and heat a space. This is achieved through the refrigerant cycle, which can be reversed in heat pumps so that they can extract heat from the outside air (even in colder temperatures) and transfer it indoors for heating, as well as perform the standard cooling function like an AC.

This differentiating feature of a heat pump makes it a more versatile HVAC solution, particularly in moderate climates where both heating and cooling are required. Understanding this fundamental operational difference is crucial for anyone working in or studying HVAC systems, as it influences equipment selection, energy efficiency, and overall system design.

The other choices present characteristics that may apply to various models or systems but do not define the core operational difference between AC and HP.