Ask two general sources how long dishwashers last and you get the same answer: about 9 years. That's the figure in InterNACHI's life expectancy chart, and it matches the National Association of Home Builders study reported in 2007. How often the machine runs, and whether hard water and food debris are kept out of its pumps and spray arms, decides most of where a given dishwasher lands.
Typical lifespan
InterNACHI lists dishwashers at 9 years with regular maintenance. The NAHB's study of housing component life expectancy, done in partnership with Bank of America Home Equity, put dishwashers at about 9 years, according to a Mortgage News Daily report on the study. That report adds that the figures are not hard-and-fast guarantees, and that changing technology, styles and preferences affect how long people keep a component. So 9 years partly reflects replacement habits, not just wear.
One manufacturer claims much more. Miele says it tests its household appliances up to 20 years of use. That's a design and testing claim for Miele's own products, not an average for dishwashers in general, so the sources don't conflict so much as measure different things.
What wears out first
| Part | Typical sign of wear |
|---|---|
| Door seal and lower door gasket | Drips at the bottom corners of the door, a seal that looks flattened or cracked |
| Filters | Dishes coming out gritty, odor, slow draining |
| Spray arms | Arms that don't spin freely, clogged jets, missed spots on the top rack |
| Racks and tines | Chipped coating and rust spots on the tines |
| Drain pump | Water left in the bottom after a cycle, a hum with no draining |
| Wash pump and motor | Weak spray, louder humming or grinding during the wash |
| Door hinges and springs | A door that drops open hard or won't stay partway open |
What shortens its life
- •Filters that are rarely cleaned, so debris reaches the pumps and spray arms.
- •Untreated hard water, which can build scale on the heater, the spray arm jets and the valves.
- •Running it heavily overloaded, so arms hit dishes and racks bend.
- •Leaning on or loading heavy items onto an open door.
- •A cabinet installation that isn't level or secure, so the door seal doesn't meet the tub evenly.
What helps it last
- •Clean the filter on the schedule in your manual, and more often if the dishwasher runs every day.
- •If your model has a water-hardness setting or a built-in softener, set it for your water, and use rinse aid as the manual directs.
- •Scrape off large food before loading.
- •Load so the spray arms can turn freely.
- •Wipe the door seal and the bottom edge of the door now and then.
Signs of age vs. signs of a fixable fault
Aging looks like a slow decline across the board: racks rusting in several places, seals that look tired all around, cleaning results that drift downward over months, and a machine that's louder overall than it used to be.
A single failed part usually has a clear start and one symptom. Water left in the tub, a hum with no draining, or a dishwasher that suddenly stops filling are classic single-fault signs. A drip from one door corner is too. Rust on racks is a wear item you can deal with on its own; see dishwasher rack rust. For anything you can't narrow down, our dishwasher service can check the pumps, valve and seals.
Sources
- •InterNACHI: Life Expectancy Chart for Homes
- •Mortgage News Daily: How Long Will That Furnace Last? NAHB Study Has the Answer (2007)
- •Miele USA: Good Reasons for Choosing Miele
Takeaway: General sources put a dishwasher at about 9 years, and clean filters plus control of hard water do the most to help one go longer.
If your dishwasher has started leaving water behind or cleaning poorly, call True Fix Chicago at (312) 896-8111 to book a visit.