Permits are not required for which type of heating appliance?

Permits are typically required for stationary, central, and permanent heating appliances due to their fixed installation and potential impact on building safety and local codes. These types of appliances are often subject to more stringent regulations because they can pose significant risks if not installed or maintained properly, such as fire hazards or gas leaks.

On the other hand, portable heating appliances, such as space heaters, are designed for temporary use and are not permanently installed. Because they can be easily moved and do not require significant alterations to structures, they generally do not require permits. This ease of use and flexibility allows individuals to utilize portable units without going through the often lengthy and complex permitting process that is associated with more permanently installed systems. Therefore, the distinction between portable and other types of heating appliances is the key factor in determining whether a permit is necessary.