If your dishwasher is leaving food on plates or glasses are coming out cloudy, the cause is almost always one of three things: a clogged filter, blocked spray arms, or water that isn’t hot enough. A few quick checks take under ten minutes. If those don’t clear it up, you’re looking at a mechanical issue and that’s where a tech needs to step in.
Start With the Filter
On most dishwashers built after 2010, there’s a cylindrical filter at the bottom of the tub under the lower rack. Pull the rack out, twist the filter counterclockwise, and lift it out. If it looks like a mat of grease and food particles, rinse it under hot water with a soft brush and dish soap, reinstall, and run a cycle. This one check clears the majority of cleaning complaints.
Older machines had self-cleaning filters with a grinder (they were loud). If yours is newer and quiet, it has a manual filter that needs monthly cleaning.
If the filter is clean or cleaning it doesn’t help, keep reading.
Check the Spray Arms
The spray arms are the plastic pieces with small holes that spin and push water at your dishes. Those holes clog with mineral deposits over time.
Pull the racks out and look at both arms. Spin each one by hand to confirm it rotates freely. Hold them up to the light and look for blocked holes. A toothpick can clear visible blockages. Also check that nothing in the rack is hanging down and stopping an arm from spinning. A long pan handle or a cutting board laid flat will stop it cold.
If the arms spin freely and the holes look clear, the problem is likely inside the machine.
Water Temperature
Dishwashers need water around 120°F to dissolve detergent and cut grease. Run the hot water at your kitchen sink until it’s fully hot, then check with a thermometer. Below 120°F is contributing to the problem.
Running the hot tap for 30 to 60 seconds before starting a cycle purges the cold water sitting in the supply line and lets the machine fill hot from the start. If your water heater is consistently running low, that’s a separate issue worth addressing, but it’s a plumber call, not a dishwasher repair.
Hard Water
If dishes come out with a white film or spots, you’re dealing with mineral buildup. In the Tri-Valley and East Bay the water runs hard, so rinse aid isn’t optional here, it’s regular maintenance. Running an empty cycle with a cup of white vinegar on the top rack every few months helps break down scale. Dedicated dishwasher cleaner tablets work too.
Loading Habits
Dishes need to face the spray. Bowls angled upward collect water instead of letting it drain off. Nested spoons block each other. Worth a quick look before assuming the machine is at fault.
What a Tech Finds When Cleaning Doesn’t Improve
When we send a tech for a cleaning complaint, they start with the filter and spray arms. That covers most cases. If those are clear, they’ll run a short cycle, watch the arm rotation, check whether the detergent dispenser opens at the right time, and verify water temperature.
If the problem persists, the next suspects are the wash pump and impeller. A worn pump doesn’t generate enough pressure to push water through the arms at full force. You can sometimes hear it as a noticeably weaker wash cycle. A clogged inlet screen, a failing heating element, or a faulty water inlet valve can all cause the same symptoms. Those components need disassembly to reach and test, and diagnosing them without the right tools and model knowledge usually makes things worse, not better.
Call Us If the Basic Checks Don’t Fix It
Do the filter, spray arms, and loading checks first. If dishes still come out dirty after that, you’re looking at a pump, valve, or internal component issue. Pulling a dishwasher apart without the right tools is how a modest repair turns into a much bigger one.
My team at adriumservice.com handles dishwasher repairs across the Tri-Valley and East Bay. We’ll get you on the schedule fast, often same or next day when we can. Call or book online.