KitchenAid Microwave Repair

Over-the-range KitchenAid microwaves do two jobs, cooking and venting the range below, and many problems involve the venting side. The exhaust fan motor wears and gets noisy, and if the thermostat fails, it may keep running with nothing on the burners. That thermostat is meant to start the fan by itself when the cooktop gets hot, so a fan that comes on alone is not always a fault.

KitchenAid also sells built-in microwaves designed to sit with its wall ovens, and some add convection. All share one heating core: a magnetron supplied by a high-voltage transformer, with a diode and capacitor. A unit that lights, turns and hums but leaves food cold has usually lost one of those parts. Convection versions add a rear element and fan of their own, each able to fail independently.

Door interlock switches wear with use, and a failing one can keep the unit from starting or blow its internal fuse. Keypads and touch panels lose response over time, often because steam and grease from the range below work into them. If you see sparking inside the cavity, stop using it until it has been checked. Grease filters under an over-the-range unit need regular washing.

Make sure the door latches with a firm click and nothing on the latch is broken. After a storm or outage, switching the breaker off for a minute often resets a frozen display. Wash the grease filters. Never open the cabinet yourself, since the capacitor can stay charged after the power is off. Note whether the problem is heat, the fan, the light or the keypad; it helps us plan the visit.

We discharge the high-voltage circuit first, then test the interlocks, transformer, capacitor, diode and magnetron, followed by the control and keypad. Over-the-range units also get a fan and thermostat check, and some units must come down for repair. Interlocks, fans and keypads are reasonable fixes. A magnetron on an older OTR unit may not be, while built-in and convection models justify more.