What type of appliances use oil as fuel and require combustion air?

Oil-fired appliances are designed to utilize oil as their fuel source for combustion. These appliances typically include systems such as oil furnaces, boilers, and water heaters, which depend on the combustion of oil to produce heat.

In the combustion process, oxygen from the air reacts with the oil fuel, generating heat necessary for the appliance to function. Thus, combustion air is essential for these appliances to operate efficiently and safely. Proper ventilation and air supply systems must be in place to ensure adequate combustion air is available, preventing incomplete combustion, which can lead to dangerous byproducts, such as carbon monoxide.

The other types of appliances mentioned utilize different fuel sources: gas-fired appliances rely on natural gas or propane, electric appliances use electricity for operation (thus not requiring combustion air), and propane appliances, while similar to oil-fired appliances in that they do require combustion air, specifically utilize propane as a fuel source rather than oil. Therefore, oil-fired appliances are uniquely identified by their dependence on oil for combustion and the corresponding need for combustion air.