Why Your Dishwasher Leaves White Residue On Dishes

Opening your dishwasher in the morning to find plates covered in unsightly streaks is a real drag. It's even more of a bummer if you've already spent time removing food particles in the filter and clearing any blockages in the spray arms. So if all the stuff you've already tried isn't working, what else could be the cause of those pesky residues?

Firstly, an excessive amount of detergent can leave a soapy white film on your dishes. This is an easy fix if you use dishwasher powder; simply use a bit less and run your dishwasher as normal to see if it makes a difference. However, if you tend to use dishwasher tablets that come in single measures, you may need to experiment with a different brand. Some dishwasher tablets also contain rinse aid, which allows water to run off crockery and cups more easily so they can dry off faster, reducing the risk of streaks, spots, and residue.

Hard water is the second cause of white residue; the minerals in the water can leave unsightly deposits on the surface of crockery and cutlery in the form of limescale. The best way to combat hard water and limescale in your dishwasher is to refill the softener unit, usually found at the base of your appliance, with dishwasher salt. These coarse grains of sodium chloride are specifically made for use in dishwashers (so don't be tempted to use regular table salt!) and prevent limescale buildup inside your machine.

If your plates have a white residue that can be wiped off with a finger, your dishwasher may be consuming too much salt — keep in mind that limescale buildup can't be wiped off as easily and requires scrubbing off with vinegar. To solve this issue, make sure the cap on your salt unit is screwed on properly and adjust the salt setting so it suits the water hardness level in your area.

After making all these changes, run your dishwasher on a regular cycle if you're only washing a regular load of dinner plates and glassware. However, make sure you choose the heavy cycle setting on your dishwasher if you've filled it with large, grimier items, like pots and pans. This should give you a clearer indication of whether your modifications have worked. If none of these tricks have solved the problem and your dishes are still coming out streaked or dirty, it might be time to consider an appliance upgrade. 

Wondering how long your dishwasher should last before replacing it? Most dishwashers last an average of 12 years, but you might need to replace yours earlier if there are signs of water leakage, mid-cycle power failures, or unresponsive buttons.