Fan obstruction

Fan obstruction means foreign matter stops an inverter cooling fan from turning or blocks its air ducts. Fallen leaves, sand, debris dropping from a weathered wall, and animals are typical causes. A blocked fan cools the inverter poorly, which triggers over-temperature protection. This cuts power generation and can damage the inverter, especially in summer. Several inverter manuals list a blocked fan as a possible cause of the external or internal fan error alarm, which is a form of fan failure. Clogged heat sinks make the fans run a higher duty cycle and shorten fan life. Dust that blocks heat dissipation and soiled air filters can also cause overheating. The risk is highest where inverters are installed outdoors near overgrown plants or bushes, or in areas with heavy ash or fallen leaves. To reduce exposure, choose a clean site away from bushes and falling debris, add protection such as sun visors, and keep the clearances given in the product manual. In service, check fan status, clean the external fan regularly with a soft brush, and check the heat sink through the fan inlets. Clean it with pressurized air if needed. When a fan alarm appears, check the fan blades and ducts for foreign objects and remove them. If the fan still does not run, contact the manufacturer.

<!-- review notes

• sentence 5: support check: partial - The passage advises against areas with heavy ash, fallen leaves, or overgrown weeds and gives a plant-overgrowth example, but it does not state that the risk is 'highest' there.
• sentence 1: review: partial - Blocked, non-rotating fans and ducts clogged by leaves, sand and weathered-wall debris are stated, but the passages describe animals as damaging fans (rodents biting cables), not as obstructing them. -->