Electric patio heaters are especially at risk in the rain, which can wreak havoc on their wiring, ceramic infrared emitters, and internal components. Rain will also discolor stainless steel. For these reasons, we highly recommend you purchase a cover for your patio heater when not in use, regardless of placement. Even if your heater is safely kept out of the rain beneath an awning, overhang, or deck ceiling, a cover will protect internal mechanisms from dust and stray moisture.