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

For an unlisted pool heater, the minimum clearance required on all sides and the rear is 12 inches. This specification is important as it ensures adequate airflow and prevents overheating, which can lead to safety hazards. Maintaining this 12-inch clearance allows for proper ventilation and access to the heater for maintenance and repair, reducing the risk of fire hazards and ensuring that the heater operates efficiently.

Unlisted pool heaters do not have the same rigorous testing and certification standards as listed units, making the recommended clearance more critical to promote safety in installations. Keeping this distance helps avoid restricting exhaust or intake air, which is necessary for combustion and functioning, thus ensuring the longevity and reliability of the heater system.