A duct reheat coil is a type of heating system that is used to provide warm air to a space. It works by taking in cold air from the outside and then heating it up using a coil that is heated by a hot gas or electric current. The heated air is then sent back into the space through a duct system. This type of system is often used in commercial buildings, such as offices and warehouses, as it is a cost-effective way to heat a large area. Duct reheat coils are also popular in residential homes, as they provide a comfortable temperature without the need for additional heating systems. The benefits of using a duct reheat coil include energy efficiency, as the system only heats the air that is needed, and cost savings, as the system is relatively inexpensive to install and maintain.