Why Your Dishwasher Isn't Cleaning Properly (And How to Fix It)

There's nothing more frustrating than opening your dishwasher to find dishes still covered in food residue. Before you call an engineer, there are several things you can check and fix yourself.

Common Causes of Poor Cleaning

1. Clogged Spray Arms

The spray arms have small holes that shoot water at your dishes. Over time, these can become blocked with food particles, limescale, or debris.

How to fix:

1. Remove the spray arms (they usually twist off)
2. Rinse under running water
3. Use a toothpick to clear blocked holes
4. Replace and ensure they spin freely

2. Dirty Filter

The filter catches food particles to prevent them from recirculating. A clogged filter is the most common cause of poor cleaning.

How to fix:

1. Locate the filter (usually at the bottom of the tub)
2. Remove and rinse under hot water
3. Scrub with a soft brush if needed
4. Clean weekly for best results

3. Incorrect Loading

How you load your dishwasher matters more than you might think:

• Don't block the spray arms - items shouldn't hang below the rack
• Face dishes inward - towards the centre for better water coverage
• Don't overcrowd - water needs to reach every item
• Angle bowls and cups - so water can drain out

4. Water Temperature Too Low

Dishwashers work best with hot water (around 55-65°C). If your water isn't hot enough:

• Run the hot tap before starting a cycle
• Check your boiler temperature setting
• Use a hotter wash cycle

5. Wrong Detergent or Dosage

Using the wrong detergent or amount can cause problems:

• Too much = residue on dishes
• Too little = poor cleaning
• Cheap tablets = inconsistent results

Tip: Use quality dishwasher tablets and check if you need salt and rinse aid.

6. Hard Water Buildup

If you live in a hard water area, limescale can:

• Block spray arms
• Reduce water pressure
• Leave white marks on glassware

How to fix:

• Keep the salt reservoir topped up
• Run a monthly cleaning cycle with dishwasher cleaner
• Consider a water softener

When It's Something More Serious

If you've tried all the above and your dishwasher still isn't cleaning properly, the problem might be:

• Faulty water inlet valve - not enough water entering
• Worn pump - weak water pressure
• Broken heating element - water not hot enough
• Control board issues - incorrect cycle operation

These problems require professional diagnosis and repair.

Prevention Tips

Keep your dishwasher cleaning effectively:

1. Scrape (don't rinse) food from dishes
2. Clean the filter weekly
3. Run a hot maintenance wash monthly
4. Use quality detergent, salt, and rinse aid
5. Leave the door ajar after cycles

Need Professional Help?

If your dishwasher still isn't cleaning properly after trying these fixes, our engineers can help. We'll diagnose the problem and provide a fixed-price repair quote.

Common repairs include:

• Spray arm replacement
• Pump repair/replacement
• Inlet valve replacement
• Heating element replacement

Get your fixed price now or call 0330 822 7695.