Think of it – relaxing after a nice dinner, talking about the day, and enjoying some well-deserved down time. Sounds great, doesn’t it? What if your dishwasher wasn’t working and you, your wife, and the kids couldn’t relax just yet because the dishes need to get done?

Surprisingly, we can trace most dishwasher issues back to the operator (that’s you). But what you probably don’t know is they’re easy to solve when you understand how they work and how to make them run their best. See, it’s not you, it’s only because you weren’t trained well.

That’s what I’ll be discussing here. Welcome to the dishwasher edition in our Getting Started Series presented by none other than our favorite group of DIY Online Appliance aficionados known as Neli!

What will you learn today?

  • I’ll describe typical dishwasher operation such as what happens when you close the door and press START.
  • How to troubleshoot and solve two common “washability” issues.
  • When you should contact Neli for a helping hand.

Basic Washing Operation

Dishwashers clean dishes much like a touchless car wash. It uses high pressure water mixed with a special soap designed to clean dishes. After washing, rinsing occurs followed by a drying cycle to finish.

You may wonder why dishes take forever to clean. Lots of things happen internal to the dishwasher causing wash times to vary. Water temperature sensors and turbidity sensors (water clarity) affect wash times.

If your dishwasher uses a digital display, the time shown is an estimate and varies or appears to get stuck and not move. More about this in the Washability Section.

As water gets pumped into the dishwasher, the upper and lower spray arms move and spray water on the dishes. If your dishwasher offers options such as upper rack only, or turbo wash, pressure changes from upper only to lower (turbo) only, depending on the option chosen.


Before rinsing, the dishwasher drains and brings in fresh water and starts a similar wash-like action without soap. It’s during this cycle the dispenser pulses its solenoid and releases a measured amount of Rinse Aid into the rinse water.

Some people refuse to use Rinse Aid, but it’s designed to increase overall washing performance. It helps water drain in sheets from dishes, reducing water spots and help dry, too. Using Rinse Aid or any other rinse agent is your choice but knowing how well it works might change your mind.


Picture of modern dishwasher with door open slightlyAfter the final rinse, the heater turns on and starts its drying cycle. If you prefer to air dry the dishes, crack the door after the final rinse, or select the option for air dry. Most dishwashers use an exposed heating element for drying. It’s located inside on the bottom and gets very hot. Don’t touch it!

Some newer dishwashers offer air dry only, so watch for this when shopping for a new unit.

Others use a combination of forced air through a heated chamber on the bottom of the sump assembly inside, near the lower spray arm. Heads up – this option doesn’t perform well.

Washability Issues

  1. Takes too long to wash. One of the more common complaints we receive is the dishwasher washes for three or more hours and dishes aren’t clean. Three hours is about the limit for any dishwasher working normally in extended cycles such as sanitize or sensor wash.

Solution: Aside from a normal three-hour cycle, the turbidity sensor or main control usually is the blame for this. We define turbidity as the clearness of the water. If the dishwasher is dirty from prolonged use, food particles build up in the sump and mix with fresh water used for washing and rinsing.

As wash water passes through a turbidity sensor, it can shorten a cycle too much, or cause extended cycles over three or more hours. If the sensor fails, either can happen with dirty dishes as a result.

When a working sensor detects dirty, cloudy water, it directs the dishwasher to pause its wash cycle, drain, and bring in fresh water to help clean the wash water. The function adds significant time to the cycle.

You’ll notice something isn’t right when the display seems to get stuck on say, 2.5 hours or 150 minutes and doesn’t move – ever. Suspect a failed turbidity sensor or main control. If so, contact us for an appointment to walk you through the repair.

TIP: Use dishwasher cleaner monthly to keep it running its best (i.e. Dishwasher Magic by Glisten).

  1. Dishes don’t dry. Believe it or not, dishwasher heaters rarely fail today. Not so long ago, a common replacement part was a heater and control for most models. Gradually, manufacturers lowered the output of their heaters to rely more on Rinse Aid and venting to dry dishes.

Solution: Take my advice to use Rinse Aid. Also, watch your soap usage! A tablespoon is all that’s needed for any size load. Do NOT use the Pre-Wash section of the dispenser – ever. Pods are OK, but they’re borderline over soaping your dishwasher. If you use them, be sure to use Dishwasher Magic every month to clean out excess soap.

A telltale sign of a bad heater aside from wet dishes is lukewarm wash water on a high-heat or sanitary cycle. Before spending money on parts, contact us first for help in pinpointing the problem.

TIP: Use a tablespoon of good liquid soap for best results with no risk of over soaping.

I hope you gained insight on dishwasher operation. They’re amazing machines! Changes over the years make them indispensable tools for convenience, but like anything, issues come and go. Now you have a better understanding of how they work and maybe you’ll be inclined to figure out a solution before spending your hard-earned money on a repair you can do yourself!

As always, Neli is only a few clicks away! Reach out to us for DIY appliance repair help, any time, night or day!  If you liked what you read here today, please leave a comment below. You know we love hearing from you!

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