RP Appliance Tech Services
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Dishwasher problem

Dishwasher Not Cleaning Dishes? Diagnose Water First, Motor Second.

Dishes coming out dirty almost always traces to one of three things: water flow, mechanical wash action, or detergent. We work the diagnosis in that order — fast and methodical.

Common causes

What's actually wrong

Clogged spray arms

Hard water on Long Island calcifies the spray nozzle holes. Dishes don't get hit with water properly.

Water inlet valve weak

Insufficient fill volume — dishwasher runs but with too little water for proper wash action.

Wash pump / motor failing

The pump that circulates water during wash cycles. Failure or weak performance reduces cleaning.

Wrong detergent or no rinse aid

Sometimes the simple fix. Cheap detergent + hard water = bad results.

Filter at the bottom clogged

Most modern dishwashers have a manual filter that needs cleaning every 1-3 months.

Before you call

Quick checks you can do

  • Pull out and clean the filter at the bottom of the wash tub.
  • Spin both spray arms by hand — if they catch or won't spin freely, they're clogged or worn.
  • Run a vinegar cycle (1 cup white vinegar, no detergent, hot cycle) to descale.
  • Verify the rinse aid dispenser is full.
When to call us

If detergent and basic cleaning don't help, we diagnose water inlet pressure, motor performance, and pump health in one visit.

Call (631) 316-1756
Brands we service

Common on these brands