What is the minimum distance a draft hood relief opening must be from any surface except that of the appliance it serves?

The minimum distance a draft hood relief opening must be from any surface except that of the appliance it serves is 6 inches. This requirement is essential for ensuring proper venting and ventilation. The draft hood is designed to allow combustion gases to exit the appliance effectively and maintain a negative pressure environment, which helps to prevent backdraft and the accumulation of harmful gases.

Maintaining a distance of at least 6 inches from other surfaces ensures that there is sufficient airflow and prevents potential obstruction, which could interfere with the proper functioning of the appliance and create safety hazards. It also allows for proper dissipation of heat and keeps adjacent structures safe from heat damage. This spacing requirement applies to various appliances, ensuring consistent safety standards across installations.