EnerG+ Infrared Electric , HEA-21533 Owner's manual

Hello! I've analyzed the user manual for the ENER+ Infrared Gazebo Heater model HEA 21533. This document provides assembly instructions, safety precautions, cleaning details, and specifications. The heater is designed for spot heating and includes features such as a remote control, adjustable mounting support and dual heat and light functionality. I'm ready to answer any questions about this device.
Where should I not use this heater?

What is the minimum clearance required for this heater?

What is the required minimum size and rating of the extension cord?