DIY repair and troubleshooting for common dishwasher problems

How to make your dishwasher repair DIY

How to repair your dishwasher

  • When it’s not cleaning well
  • When it won’t start or fill
  • When it won’t drain or dry
  • When it overflows and leaks
  • When you’d like to save energy

Is it worth fixing a dishwasher?

Are dishwashers easy to fix? In short, your answer to both questions is often and yes, as long as you’re up for it. Doing it yourself (DIY) is a great way to save money, get to know your home’s appliances – in this case, your dishwasher – and feel the accomplishment and relief of fixing a problem without having to call a professional.

If you muster some courage along with a determination to learn, diagnose problems, order parts and sacrifice a little free time, you too can make your dishwasher repair DIY and subvert the cost of a local repair man. If your dishwasher is acting up, unless you’re facing an emergency, most fixes are usually pretty simple and easy. Once you know the symptoms and how to troubleshoot, you’ll often be well on your way to a quick fix. If you have the manual, read it, but if you don’t, you might easily find it online.

A dishwasher is a pretty simple machine. It’s essentially a watertight box that squirts a few gallons of heated water, mixed with detergent, all over a bunch of dishes, rinses, drains and then repeats the whole cycle a few times to clean the dishes. It might also dry them, but that’s really it. The whole thing relies on a heating element, a timer and a good seal. Water comes in through a supply valve under the sink and connects to the dishwasher’s inlet valve, which in turn supplies the water to the spinning arms inside the machine. Dirty water drains at the end of each cycle through a drain at the bottom and a drainpipe directing it out from the dishwasher. If your water isn’t hot enough (120F-140F – check the manual), or if it’s too hard (try testing it), you could have a problem unrelated to your dishwasher, so you may want to look into these possibilities first.

Before you begin

Before you go full DIY, grab a bucket and a few tools to have handy while you’re crouching and crawling, like a headlamp, knee pads, screwdrivers and pliers. Put some warm, soapy water in a second bucket and grab a few rags, a sponge, rubber gloves and an old toothbrush. If you need to pull your dishwasher from underneath your counter, make sure it’s cool and dry before doing so.

Go ahead and turn off the electrical circuit it’s tapped into via your breaker box, and while you’re at it, turn off the water supply valve under your kitchen sink, along with the dishwasher’s drain and supply lines. Unplug the power cord. Open the door, remove the frame screws and gently move it toward you, but keep in mind that it is likely to tip over in your direction.

When it’s not cleaning well

It’s a bit of a buzzkill when your dishwasher leaves spots on glasses or when some sort of nasty film lingers on your dishes. If your water is hot enough and you’re scraping your plates thoroughly, you should be good, as long as you’re not experiencing hard-water problems, overloading the dishwasher, obstructing the spray arm with an errant bit of silverware or using regular dishwashing detergent.

Sometimes these poor-performance problems are a result of clogged spray arms or a bad water inlet valve. You should be able to solve either issue without extracting the machine from its resting place. After pulling out the racks, simply unscrew the cap to release the arms, and pull them out for a good soak in vinegar. A little water left beneath them in the tub is normal.

If you need to get at the inlet valve, pull out the access panel and remove the water line running into the inlet valve. Then take off the brass fitting and pull off the valve bracket and electrical harness. Pop in the new valve fitting after winding Teflon tape around its threads to maintain a solid water seal. Reverse your steps, and voila! Your next cleaning cycle should sparkle like a dish-soap ad.

When your dishwasher isn't cleaning well, another possibility worth checking out is the float switch, which can get stuck in place. A stuck float switch keeps the tub from filling with enough water for a cycle, thus impeding the cleaning. Float switches are usually found near the front of the tub. Get in there and scrub a little, and you should free it up quickly enough. 

A dirty valve screen can also muck up your intake, so run the machine and open it in the middle of its second cycle to check on the water level. If it isn’t filled up past the heating element, it’s not getting enough water, which means that your intake valve screen is likely blocked. Shut the door again, and let the machine finish. After opening it again and letting it cool, come back around and clean that intake valve screen, but first, cut the power to the machine and turn off the water supply. Remove the lower panel and disconnect the valve. Flush the system briefly with water from the supply tube to help clear the screen, and then reverse your steps. If your dishes aren’t sparkling after your next wash, it might be time to call a professional.

When it won’t start or fill

When you turn on your dishwasher and neither hear nor see a single sign of life, your machine probably isn’t receiving power or water. Make sure the door is fully shut and reliably engaging the system when it shuts, as intended and explained in the manual. Check the breaker and the GFCI outlet to make sure the outlet or the circuit doesn’t need a reset. The problem could be a timer or selector switch issue, often best addressed by a pro.

When your dishwasher’s lights are on but nobody’s home, you know something’s amiss. Perhaps you hear a hum, but there’s no water movement. Turn off the power to the machine. Put on some gloves and try to spin the fan blade on the motor underneath the dishwasher by hand. Now turn it on and try again. Still nothing? Cycle the circuit breaker to make sure it hasn’t tripped. If the blades still won’t turn, you’re going to need professional help. If you get them spinning again, but the machine still refuses to go into its cycle as normal, you may have any number of additional issues – like a bad pump, a broken switch or something else best diagnosed by a professional. 

If the dishwasher runs without filling, first check the water supply line to make sure water is coming in. Next, examine the hot water supply shutoff valve, typically found under the sink. This should be open wide. Move on to cleaning the float mechanism with a damp cloth, and then check the water inlet valve to make sure it’s free from debris.

When it won’t drain or dry

As we’ve noted, a bit of water lingering in the tub is normal and good for keeping certain valves wet, but too much water failing to drain can point to potential problems like damaged pumps or clogged drains or hoses. Sometimes you can clear a blockage like this easily by hand. You should be able to tell if the drain filter is clogged. Next, look for kinks or clogs in the drain hose, then take off the air gap cover at the back of the sink and clean it with a wire. Unscrew the cap under the lower spray arm and clean it out with a brush and some warm, soapy water. If your sink backs up when you test the water flow, you likely have a clog in your main sink drain.

If you suspect the main drain line that’s leaving the dishwasher, disconnect all the power and remove the machine completely to access this drain and check it for clogs by blowing air into it. If it must be cleared, detach it and run it into the sink until water pressure pushes through the clog. 

If the dishes are still wet after the end of the cycle, the heating element at the bottom of the tub is likely at fault. Luckily, this is a cheap and easy fix. First, disconnect the machine from power, unplug the wires on the back and set them aside, noting their respective positions. Unscrew the retainer nuts that hold the element in place and lift out the heating element. After you’ve found a replacement, carefully reverse your steps.

When it overflows and leaks

If you’re getting a constant flow of water to and from the dishwasher which fails to stop automatically and turns into an overflow, you may have a faulty float switch. Sometimes it’s easy to fix a stuck float switch by merely moving up and down a little by hand. If this doesn’t work, you can test the float switch with a cheap multimeter to see if it’s functional.

First, unplug the dishwasher. Then, lift up the plastic float switch. If this dome-shaped switch won’t budge, remove its plastic top, clean the stem, and then put the dome back in place. Now, the float should move up and down. Take note of the wires attached to the float switch terminal, in case you have to replace the switch. Set your multimeter voltage/ohm dial to Rx100. Touch the terminals with the two probes. When lifting the float, the testing needle should read infinity, and when it drops, it should read zero. If not, you need a new switch. Simply unscrew or unsnap it from the tub, get a replacement part and reverse your steps. This small part should fit into the palm of your hand and is not difficult to replace.

If you notice evidence of leaks, like drips under the door, make sure you’re using a dishwasher-only detergent, as others can cause excess foaming which can contribute to leaks. Make sure you’re not overloading or causing a door obstruction, which can force spillage, and make sure the machine is level on your floor. Dishwasher leaks are often attributable to the main gasket around the rim of the door, also known as the door seal, so take a closer look with a flashlight for any damage or build-up. 

If the seal looks dirty or grimy, take the opportunity to clean it. If it’s damaged, you should be able to replace the entire gasket/seal. You can use a hairdryer to straighten out a new seal after removing it from the package. Sometimes the door itself could need a little attention, particularly if it’s not latching tightly or seems loose. There should be a latch plate at the top of the dishwasher frame, which you can tighten to make the door shut more securely. If you still have a leak, remove the lower front panel to check for leaky hoses, a broken pump seal or perhaps corrosion, but at this point you’re getting into more challenging repair territory.

When you’d like to save energy

Who doesn’t like to save energy? How you choose to operate your dishwasher can impact your energy usage and the amount of your utility bill. Luckily, saving energy is easier on the environment as well as your wallet. It’s always important to scrape away food before putting dishes in the dishwasher, but try not to use much water. Don’t run the dishwasher until it’s full, but don’t overfill it, either. Turn on an energy-saver mode if there is one, or use a shorter cycle to use less energy and less water, and let your dishes air dry. These tips will help you get more out of the machine while using less energy and less water.

If you’ve ever asked yourself, “How do I fix my dishwasher?”, hopefully you’re feeling more confident in your dishwasher repair DIY skills after reading this post. We hope you’re no longer feeling lost in the whirlpool of facts and advice that can make dishwashers sound a lot more complex and difficult to master than they really are. 

Meanwhile, if you’re wondering whether a home warranty covers the dishwasher, would like a few more tips to get the most out of your dishwasher or might appreciate a dishwasher maintenance checklist, all of us at Cinch Home Services are happy to share what we know. If you’d like to read more about home appliance maintenance and DIY home repair tips in general, subscribe to our newsletter!


The information in this article is intended to provide guidance on the proper maintenance and care of systems and appliances in the home. Not all of the topics mentioned are covered by our home warranty or maintenance plans. Please review your home warranty contract carefully to understand your coverage.
 

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