Large stainless refrigerator set flush between kitchen cabinets

Generic photo: Alex Qian · Pexels License

Install a countertop microwave as a built-in with a trim kit

A trim kit lets a specific countertop microwave sit in a cabinet opening with a finished frame and proper airflow. Only the kit listed for that microwave model can be used, and the cut-out size, outlet location, ventilation openings and any wall-oven combination are set by the kit's instructions. Most callbacks come from the wrong kit, an outlet behind the unit, or blocked airflow.

Cross-checked ~90 min moderateBrands: All

Before you start

Unplug the microwave before fitting it into the kit; never work inside the microwave cabinet.
Use only the trim kit the microwave maker lists for that model; other combinations can overheat.
A new outlet in the cabinet is electrical work: a qualified electrician where required by local code.
Some kits are approved over a wall oven only with specific oven types; check before installing.

Diagnostic steps

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