Nobody calls a technician the first time a plate comes out gritty. They rinse it, run the machine again, and get on with their day. Six months later everything needs a second wash and the glassware has gone permanently cloudy.
That gap is why dishwasher faults are usually several small problems stacked together rather than one dramatic failure. The upside is that most of them are free to fix.
Work through these in order. Stop when the dishes come out clean.
1. The filter
At the bottom of the tub, under the lower spray arm, there is a cylindrical filter that twists out. On most machines it has a fine mesh screen around a coarse plastic cage.
Pull it out and look at it. If you have never done this, prepare yourself.
Rinse it under a hot tap, scrub the mesh with a washing-up brush, and check the recess it sits in for anything solid. Broken glass, olive pits and fruit stickers are the usual finds.
Do this monthly. It is the single highest-value thing you can do for a dishwasher.
2. The spray arms
Lift out the lower arm, which usually unclips or unscrews by hand, and take out the upper one too if it comes free easily.
Hold each up to a light and look through the jets. Blocked holes are obvious once you look. Clear them with a toothpick or a straightened paperclip, then run water through the arm from the centre hub to flush the debris out rather than further in.
While the lower arm is out, spin the mounting hub. It should turn freely.
3. The water temperature
A dishwasher needs water arriving at around 120°F to dissolve detergent properly. Colder than that and the detergent never fully activates, which produces exactly the gritty film people describe.
Run the kitchen hot tap until it is genuinely hot before starting a cycle. If the tap water never gets there, the problem is the water heater, not the dishwasher.
This also explains why the last load of the day sometimes comes out worse than the first.
4. Rinse aid and hard water
Greater Boston's water is hard enough to matter here. Hard water leaves mineral deposits on glassware that look like permanent cloudiness, and it reduces detergent effectiveness.
Fill the rinse aid reservoir and keep it filled. Rinse aid is not a luxury additive; it changes the surface tension of the water so it sheets off rather than beading, which is what actually dries your dishes and prevents spotting.
If glasses are already cloudy, run an empty cycle with a citric acid dishwasher cleaner. If the cloudiness does not shift, it is etching rather than deposit, and that is permanent.
5. Loading
Worth saying because it is genuinely common. Dishes that shield each other do not get washed. A baking tray laid flat across the bottom rack blocks the entire lower spray arm. Bowls facing up fill with dirty water.
Before you close the door, spin both spray arms by hand. If either catches on anything, rearrange.
When it is actually broken
If you have done all five and dishes still come out dirty, the likely faults are a wash pump that has lost pressure, a water inlet valve that is underfilling, or a heating element that is not raising the water temperature during the cycle.
All three need a technician. The heating element also explains dishes that come out clean but soaking wet, since the drying phase is just residual heat on most machines.
See what a dishwasher repair involves.
FAQ
Why does my dishwasher smell?
Trapped food in the filter and the spray arm jets. Steps one and two above fix nearly every case. If the smell survives that, the drain hose is holding standing water.
My brand new dishwasher will not drain at all.
Check whether a garbage disposal was fitted or replaced recently. Disposals ship with a knockout plug in the dishwasher inlet, and forgetting to remove it is the most common cause of a new dishwasher that will not drain.
Should I rinse dishes before loading?
Scrape, do not rinse. Modern detergents need some food residue to work against, and heavily pre-rinsed loads can actually come out worse.
How long should a dishwasher last?
Ten to twelve years is normal. Past that, a major component failure is usually the point at which replacement makes more sense, and we will tell you when we think you have reached it.
Dishwasher repairs across Greater Boston and Southern New Hampshire, including built-in and panel-ready units.
