What is the minimum clearance required for an unlisted pool heater on all sides?

The minimum clearance required for an unlisted pool heater on all sides is 12 inches. This clearance is essential to ensure adequate ventilation and access for maintenance, as well as to prevent the risk of fire hazards. Adequate space around the heater allows for proper airflow, which is critical for safe operation. Keeping a distance of 12 inches helps to avoid any heat buildup, which can occur if the heater is positioned too closely to combustible materials or surfaces. Furthermore, this clearance requirement aligns with safety standards set by various codes and regulations, ensuring that the installation minimizes risk while promoting efficient functioning of the heater.