Why Does Your Dishwasher Leave White Film on Your Glasses?

Many of us enjoy the sensation of sparkling clean items coming out of our dishwasher. So, it can be very disconcerting when your glassware has a white film on it. Although your glasses are clean, this film can be unappealing and ruin the aesthetics of your glasses. So, what causes this film and what can you do to correct it?

Image of a kitchen with an open dishwasher

Hard Water

One of the most common reasons for glassware film and etching is hard water. Hard water contains higher levels of minerals, particularly calcium and magnesium that can create a number of issues around the home including creating white marks on surfaces that come into contact with water. If you notice that there are white stains on fixtures, taps and other areas of your home, your white film may be due to hard water. If the problem is localized to your dishwasher, you may need to investigate further.

Hard water can leave mineral accumulation inside appliances, pipes, and fixtures, but it can be corrected with a water softener, conditioner or filter. These devices remove the calcium and magnesium particles and can often be tailored to remove other potentially problematic water contaminants.

You’re unnecessarily Pre-Rinsing

In older dishwashers, pre-rinsing was essential for a thorough clean, but this is not necessarily the case now. Modern dishwashers are designed for energy and water efficiency, so pre-rinsing can actually cause problems such as white film on glasses. The reason for this is that most dishwasher detergent products contain phosphates. Phosphates require food residue to be present in order to break down. So, if you’ve already rinsed the grease or food residue from your dishwasher load, the phosphates can end up collecting on your glasses. To avoid this problem, you can try to find a phosphate-free dishwasher detergent, but an easier solution is to choose an appropriate dishwasher cycle. Don’t just put every load through a normal load cycle. Make use of the features and wash cycles on your dishwasher to choose the one more appropriate to your dishes. Most dishwashers even have a glassware cycle, so you can enjoy crystal clear, sparkling glasses.

Correcting the Problem

Although it is tempting to simply run affected glassware through another dishwasher cycle, this is not likely to solve the problem. Regardless of whether the white film is caused by phosphates or hard water, exposing your glasses to more of the same will not correct the issue. Instead, if you find that you have a rack full of glassware covered in film, run a warm vinegar rinse cycle. This will use less water and should correct the problem. All you’ll need is 2 cups of white vinegar, placed in a dishwasher-safe cup or glass. Put this on the bottom rack and run the dishwasher on a complete wash cycle with an air dry option. You’ll not need any detergent in this cycle as the vinegar will mix with the dishwasher water to create the film eliminating effect.

White vinegar will also be effective at cleaning any hard water residue that may have accumulated inside your dishwasher. Although it may have a strong odor, you don’t need to worry about drinking out of vinegar scented glasses, as the odor will dissipate quickly during drying. For this reason, it’s a good idea to run a vinegar cycle a few times a year to ensure that your dishwasher is clean and fresh.

If you’re still having some difficulties with your dishwasher, you can rely on a professional appliance repair specialist for a long-lasting, effective solution. For help with all of your dishwasher repair needs, be sure to speak to a professional appliance repair service.