A unit heater is a mechanical device that can be installed in an indoor or outdoor area and works as an individual unit to provide heat for that area. These types of heaters are often connected to other systems, either for external power supplies or external gas lines, depending on the type of heater being used. They do not typically require ducting systems in place that may be required for central heating systems, and can often be mounted onto a wall or ceiling. A unit heater can be small enough for residential use, though they are often designed and installed for commercial applications.
The design of a unit heater will typically depend a great deal on how the heater produces heat and how it is intended for installation in a building. These heaters often produce extremely high amounts of heat, and so are typically designed for installation on a ceiling that is high above people. The heat is produced and fans blow the hot air down toward people, and the heat produced is often so intense it can be felt from fairly great distances, making a unit heater ideal for use in warehouses and large commercial retail outlets with high ceilings.
A unit heater can also be designed to mount onto a wall, though these heaters may produce less heat to remain safe during use. Regardless of how a heater is installed, it will typically require a connection to a power source. The most common types of unit heaters are those that run on gas or electricity. A gas unit heater is typically installed onto a building that already has a gas line, and can be used to increase heating in large areas or to provide outdoor heating to an existing structure.
Electric unit heaters are often easier to install and use, however, since they do not require a natural gas supply line. These heaters are often preferable for use in areas that may contain volatile or combustible gases, and some electric heaters are specifically designed for use in such areas. This type of electric unit heater is designed to not produce sparks or other ignition sources, making them ideal for this type of placement. Commercial unit heaters are often quite large, and though professional installation may be required, the process is typically simpler than installation of new duct work or central heating.