Why Is Dishwasher Rusting Inside

Why Is There Rust Inside Your Dishwasher?

Rust inside a dishwasher is a common problem that can appear as orange or brown stains on the tub walls, floor, or racks. Understanding where the rust is coming from is the first step to fixing it — because the source determines the solution.

Where Is the Rust Coming From?

Rust inside a dishwasher almost always comes from one of three sources:

• The dish racks: The most common source — the vinyl coating on dishwasher racks chips and wears over time, exposing the metal underneath to water and causing rust
• Rusty items being washed: Cast iron, uncoated steel, or other rusty items placed in the dishwasher transfer rust to the tub interior
• The dishwasher tub itself: Less common — most modern dishwasher tubs are stainless steel or plastic-coated, but older or damaged tubs can rust

Cause 1: Rusting Dish Racks (Most Common)

Dishwasher racks are made of metal coated with a vinyl or plastic coating. Over time — especially at the tips of the tines — this coating chips, cracks, or wears away. The exposed metal rusts rapidly in the wet dishwasher environment, and rust particles wash off and stain the tub interior orange or brown.

Fix:

• Inspect the racks for chipped or missing coating, particularly at the tine tips
• Repair small areas of damage with a rack repair coating kit — Dishwasher Rack Repair Coating is a vinyl touch-up paint that seals exposed metal and prevents further rusting
• Replace tine tips that have lost their coating with Dishwasher Rack Tine Repair Caps — these slip over exposed tine ends and restore the protective coating
• If the rack is extensively rusted, replacement is more practical than repair

Cause 2: Rusty Items Being Washed

Cast iron, carbon steel, or any item with surface rust should never go in the dishwasher. Rust from these items washes off during the cycle and deposits on the tub walls and floor.

Fix:

• Never put cast iron, carbon steel, or rusty items in the dishwasher
• Inspect all items before loading — even a small rust spot on a pan can stain the entire tub interior

Cause 3: The Tub Itself Is Rusting

If the rust is coming from the tub walls or floor rather than the racks, the tub coating or stainless steel surface may be damaged.

Fix:

• For plastic-coated tubs with chips or cracks, the exposed area can be treated with a dishwasher-safe sealant
• For stainless steel tubs with surface rust, clean with a stainless steel cleaner and a soft cloth — do not use abrasive scrubbers which will scratch the surface further
• Extensive tub rusting in an older machine may indicate it is time to replace the dishwasher

How to Remove Rust Stains From the Dishwasher Interior

1. Run an empty cycle with a cup of white vinegar on the top rack — the acid helps dissolve rust stains
2. For stubborn stains, apply a paste of citric acid powder and water to the stained area, leave for 15 minutes, then wipe clean
3. Use Affresh Dishwasher Cleaner Tablets monthly to prevent mineral and rust buildup from accumulating inside the machine

Final Tips

• Inspect racks regularly for chipped coating — repair small areas promptly before rust spreads
• Never put cast iron or rusty items in the dishwasher
• Run monthly cleaning cycles to remove rust stains before they become permanent
• Replace extensively rusted racks rather than attempting to repair large areas