By InterNACHI's life expectancy chart, the answer to how long microwaves last is 9 years, the same figure it gives dishwashers and shorter than any range. How the door is treated and, on over-the-range models, how well the filters and fan are kept up decide much of where a given unit lands.
Typical lifespan
InterNACHI gives microwave ovens 9 years and calls the figure a guideline. It doesn't separate countertop, over-the-range and built-in models. Over-the-range units also work as a range hood, so they carry extra wear parts: a vent fan, grease filters and, on recirculating installations, a charcoal filter.
What wears out first
| Part | Typical sign of wear |
|---|---|
| Door latch and hooks | A door that doesn't latch cleanly, or a microwave that stops when the door is bumped |
| Door hinges | A door that sags or doesn't close evenly |
| Turntable coupler and roller ring | A tray that stops turning or turns unevenly |
| Keypad or touch panel | Keys that need a harder press or don't respond |
| Interior light | A light that flickers or stays dark |
| Vent fan (over-the-range) | A louder fan, rattling, or weaker suction |
| Grease and charcoal filters (over-the-range) | Grease dripping from the filter, odors no longer removed |
What shortens its life
- •Running it empty. LG's manual says do not run the oven empty, without food in it.
- •Slamming the door or hanging on it, which wears the latch and hinges.
- •Letting soil or cleaner residue build up on the door's sealing surfaces, which LG's manual also warns against.
- •Grease filters left uncleaned on an over-the-range model, which restrict the fan.
- •Heat and grease rising from a busy cooktop below an over-the-range model.
What helps it last
- •Close the door gently and keep the seal area clean.
- •On over-the-range models, clean the grease filters about monthly. KitchenAid says to clean them monthly or as prompted by the filter indicator.
- •Replace a charcoal filter on the manufacturer's schedule. KitchenAid says about every 6 months, and LG's manual says every 6 to 12 months. A charcoal filter can't be cleaned.
- •Use the vent fan while cooking on the range below.
- •Use microwave-safe containers and covers so spatter doesn't build up inside.
Signs of age vs. signs of a fixable fault
An aging microwave shows it in the parts you touch: a door that doesn't close as crisply, worn keypad markings, a turntable that's a little noisier, and an interior with worn paint or coating.
One failed part, by contrast, tends to announce itself all at once. The microwave runs but doesn't heat, the turntable stops, the light goes out, or a touch pad stops responding. Those point to one part, whatever the unit's age. LG's manual says not to operate the oven if it's damaged. A microwave holds dangerous high voltage inside even when unplugged, so never open the cabinet. For over-the-range models, see range hood lifespan for the vent side, and our microwave service for diagnosis.
Sources
- •InterNACHI: Life Expectancy Chart for Homes
- •LG: LMV1680 Microwave Oven Owner's Manual (PDF)
- •KitchenAid Product Help: Cleaning the Filters, Over-the-Range Microwave
Takeaway: Most microwave wear happens at the door, and over-the-range models add grease and charcoal filters to the list.
For a microwave that's stopped heating or isn't latching right, book a visit with True Fix Chicago at (312) 896-8111.