One or more cooling fans in the inverter have failed or are not running at required speed.
Common causes
Fan bearings worn (common after several years of operation)Fan blocked by debris or insulation materialFan controller failure
What to check
STEP 1
Listen for fan noise during high load. SPH fans are audible -- silence during peak output suggests fan failure. Check ventilation slots for blockage
STEP 2
If accessible and safe, visually inspect fan blades for obstruction. Spiders and insects sometimes build nests in fan housings
Escalate if
Fan confirmed not running -- do not continue running in hot weather without fans. Escalate for fan replacement; overtemperature damage can occur quickly
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