What type of air is circulated to supply oxygen and cool the appliance?

Ventilation air is the correct type of air that is circulated to supply oxygen and cool an appliance. This air is essential for maintaining a safe and efficient operation of gas appliances, as it helps to ensure that there is enough oxygen available for combustion. Adequate ventilation air also helps to manage the temperature around the appliance, preventing overheating and ensuring longevity in performance.

While infiltration air refers to unintentional air entering a space, and combustion air specifically refers to the air directly involved in the combustion process itself, ventilation air serves a broader purpose of ensuring that there is sufficient air movement within a space. Fresh air is a concept that pertains to outdoor air that hasn’t been significantly altered by indoor pollutants, but in the context of appliances, the role of ventilation air is more specifically targeted towards creating a safe and well-ventilated environment.