Oil-fired heaters are heating systems that use oil as a fuel source to generate heat. They typically burn heating oil, which is a type of fuel derived from crude oil. These heaters are commonly used in residential and commercial buildings, especially in areas where natural gas is not readily available. The operation of oil-fired heaters involves a burner that ignites the oil, producing hot gases that heat water or air. This heated medium is then circulated throughout the space to provide warmth. Regular maintenance is essential to ensure efficiency and safety, including checking the burner, fuel tank, and venting system.