The definition of a coil heating system is a type of heating system that uses a series of coils to transfer heat from one source to another. This type of system is often used in homes and businesses to provide efficient and cost-effective heating. The coils are usually made of metal and are connected to a source of heat, such as a furnace, boiler, or electric heater. The heat is then transferred through the coils to the desired area. This type of system is highly efficient and can provide a steady and consistent source of heat. It is also relatively easy to install and maintain, making it a popular choice for many homeowners and businesses. Additionally, the coils can be easily customized to fit the needs of the space, allowing for greater flexibility and customization.