The door on this Whirlpool microwave, model KEMS309BSS00, would not close all the way, and the cause was worn door hinges. I replaced all three hinges (part number W10874474), which meant stripping the microwave down to reach them. With the new hinges the door pulls in square and latches correctly. The job ran two to three hours.
Why is my Whirlpool microwave door not closing?
Almost always it is the hardware that pulls the door in and holds it there, and that means either the latch assembly or the hinges. Those are the two I check first, in that order.
The latch comes first because it is the easiest to see. Two hooks on the door push into the latch body and trip the interlock switches. If a hook is cracked, or the latch body has shifted, the door stops short of the frame or closes without the microwave doing anything when you press start. Food debris packed into the latch opening does the same thing and costs nothing to clear.
Hinges are next. A microwave door is heavy for its size, and the hinge pivots wear oval over years of being swung open and shut. Once that happens the door hangs slightly low and twists as it swings, so the hooks no longer line up with the latch openings. You can usually feel it: the door drops a little when you let go of the handle, and you have to lift or push it to get it to catch.
Third is the door itself. The inner panel can loosen from the outer skin, or the frame can bend if the door has been leaned on or had something hung over the handle. Bent door frames are not something I straighten.
On a built-in unit, I also check the cabinet opening and the trim kit. If the unit has been pushed in crooked, or a mounting screw has backed out and let it tilt, the door will contact the frame before it seats.
What it turned out to be here
The latch hardware was intact, and the door was sagging on the hinge side, so it could never come in square enough for the hooks to seat. The hinges on this KEMS309BSS00 sit behind the outer cabinet, so in this Irvine kitchen the unit came out of the wall and came apart almost completely before I could get at them.
What can you check yourself?
Open the door and look into the latch openings on the frame with a flashlight. Crumbs, grease and the corner of a paper towel all end up in there, and clearing them out solves a surprising number of doors that will not shut.
Then hold the door half open and let go of the handle without letting it fall. If the free edge drops visibly, or the top and bottom gaps are uneven when the door is shut, the hinges are worn and the door needs to come off to fix it.
Stop there. The cabinet of a microwave covers a high voltage capacitor that holds a charge long after the unit is unplugged, and the door, hinges and interlock switches sit right against that section. Getting into it is my job, not a kitchen-table repair.
FAQ
Is it safe to use a Whirlpool microwave when the door will not latch?
No. The interlocks are what keep the magnetron from running with the door open, and a door that is not seating properly is pressing on switches that were never meant to work at an angle. If the unit ever runs with the door visibly ajar, unplug it and leave it unplugged. A door that only latches when you push it hard is also putting load on parts that are already worn.
How long do microwave door hinges usually last?
In most kitchens they outlast the rest of the microwave, but heavy daily use shortens that considerably. Hinges wear from the number of open-and-shut cycles, not from age, so a unit in a busy family kitchen can need them at eight or ten years while a lightly used one never does. Letting the door swing open and drop on its own stop is what wears the pivots fastest.
Is it worth replacing hinges or should I replace the microwave?
Hinges are worth replacing on a built-in or an over-the-range unit, because the appliance itself is expensive and often sized to a cabinet opening that a new model may not match. On a cheap countertop microwave, the labor usually exceeds what the unit is worth. The deciding factor is whether the door frame and the inner panel are still straight, since those are not repairable.
We cover microwave and built-in oven repair across Irvine and the rest of Orange County. You can book a visit online or call Cactus Appliance at (949) 544-5550.
