Oster Blocked or misdirected airflow

Microwave fan runs but there is no airflow from the front or top vents during operation.

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Obstructed exhaust duct (over-the-range models), Incorrect blower orientation, Clogged grease filters, Blocked intake vents

Safety first: Unplug the microwave before removing filters or accessing the blower.

Clean filters: Remove and clean the grease filters with warm soapy water. Replace charcoal filters if your Oster model uses them and they are saturated.
Check vent path: Ensure the external vent hood and duct are not blocked by debris or nests.
Verify blower orientation (OTR models): If recently installed, confirm the blower is oriented correctly for recirculating or external venting per the installation manual.

Medium 3/5

Grease Filter / Charcoal Filter

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