Which system is characterized by using air as the primary medium for temperature control?

The system characterized by using air as the primary medium for temperature control is the all-air system. This type of system relies on air to distribute heating and cooling throughout a building. It typically involves the use of ductwork and air handling units to regulate the temperature in various spaces. In an all-air system, conditioned air is supplied to the environment and can be controlled in terms of temperature, humidity, and quality.

In contrast, all-water systems use water as the primary medium, circulating it through pipes and radiators instead of air. Hydronic systems also use water but are specifically designed for heating purposes, often employing boilers to heat water that is then circulated. Split systems, while they may utilize air for cooling and heating, generally involve both an indoor and outdoor unit and can incorporate different methods, such as refrigerant rather than solely air, for temperature control. Understanding these distinctions highlights why all-air systems are specifically noted for their reliance on air as the medium for temperature management.