Abnormal fan noise

Abnormal fan noise is a sound you can hear from an inverter cooling fan while it runs. Technicians check for it during routine fan maintenance. Listen while the fan is turning, and check its running status at the same time. Also look for cracked blades and make sure the blades spin smoothly. Several manufacturers list this check once a year, together with a look for fan warnings or alarms in the monitoring app. On some inverters, you can switch on a fan test parameter. This lets you check for odd noises and confirm that air comes in at the bottom and leaves through the upper vents. Unusual fan noise, or missing airflow, most likely means the fans were installed incorrectly. Check how they are mounted, and contact service if the mounting looks correct. If the fan is noisy or damaged, clean it or replace it.

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• sentence 6: support check: partial - Passages say clean or replace fans if necessary after checking noise/cracks, but don't explicitly tie it to noisy or damaged condition as a rule, though it's implied. -->