Appliance Repair Service

Problem 1: Your dishwasher don't come out clean

A. Review the basics (5 minutes)

• Are you overloading your dishwasher? Check the manufacturer's instructions to make sure you're loading it right.
• Does silverware drop below the lower basket? The spray arm can't spin if obstructed.
• Are you using the proper dishwasher detergent?
• Do you routinely scrape food bits off dishes before loading them into the racks? (Rinsing is not necessary.)
• Are you using a special rinsing agent if your water is hard (highly mineralized)? Hard water can leave a film on the dishes.

Tip: Adding a water softening system can dramatically improve dishwasher performance.

• Is the water temperature high enough? This can be a complex issue.

We recommend that your household water heater be set no higher than 120 degrees F, both to help prevent accidental scalding and to maintain energy efficiency. Many dishwashers have heating elements that boost the temperature to about 140 degrees. However, some dishwashers don't have a heating booster and require household water at about 140 degrees. So first check the owner's manual for the recommended water heater setting.

If your dishwasher requires140-degree water, check the temperature of your hot water at its current setting. Put a meat thermometer in a glass and fill it at the kitchen faucet with water at its hottest point. If the temperature reads less than 140 degrees, you'll have to either risk raising the water heater setting (we don't recommend it) or consider buying a different dishwasher. But check the maintenance steps below first to make sure poor cleaning isn't caused by other factors. In any case, consult a service pro before making a buying decision.

B. Clean the spray arm (10 minutes)
Twirl the spray arm to make sure it spins freely. Also check the holes in the spray arm for debris. If you spot debris or the spray arm doesn't spin, remove the spray arm and clean it (Photos 1 – 3).

First take out the wire baskets by removing either a cap or pin at the end of the sliding tracks. Don't fret about a little water on the bottom of the tub. It's supposed to be there. It keeps the seals in the pump and in the motor assembly damp. If they dry out, they'll crack and leak.

The spray arm cap twists off with a clockwise turn, just the opposite of a regular screw (Photo 1). Twist ties, rubber bands and plastic and paper often show up in the spray arm. You might have to use a needle-nose pliers to pick them out. The pump usually sucks up most of this stuff, but if you hear a sudden loud grinding sound while running the dishwasher, something like broken glass might be stuck in the pump intake. Unscrew and remove the pump cover (Photo 2) to check it out.

C. Clean the float switch (5 minutes)
The float switch may not be a problem, but it takes only a few minutes to check it, so open it up and clean it anyway (Photos 4 and 5). Debris can cause the float to stick in the raised position, which prevents the tub from filling. If the water doesn't reach the right level (just covering the heating element), the dishwasher won't clean well. See the next section for how to check the water level.

On most models, you'll find the float switch in the lower front of the tub (Fig. A and Photo 4). Ours has a cover, but some don't. You may have to use a small, flexible brush or pipe cleaner to clean those without a removable cover. When clean, the float should slide up and down freely.

D. Clean the valve screen (30 minutes)
One common symptom of a clogged intake valve screen is a low water level during the dishwashing cycle. (Low water could also indicate a clogged float switch, but you've already taken a few minutes to check it.) So before going through the somewhat more complex steps for cleaning the intake valve screen, check the water level.

Close the door, turn on the machine and run it until it's done filling during its second cycle. Then open the door (the machine will automatically shut off), and check the water level. If the water doesn't come up to the heating element, it's too low. Close the door and let the machine cycle on through. Then proceed to clean the intake valve screen (Photos 6 – 9).

You'll have to unhook several wires, so always begin by turning off the electrical power to the dishwasher at your main panel. Turn off the water supply to the dishwasher as well. Usually the shutoff is at the hot water supply line under a nearby sink. The inlet valve is usually mounted on the underside of the dishwasher near the front.

You have to remove the lower panels (Photo 6) and disconnect the valve (Photos 7 and 8) to get at the valve screen, a wire screen mounted within the body of the valve itself (Photo 9). If the wires don't pull off readily, push the small spot in the center of the connector to release them. And mark one wire and its terminal with tape so you can get them back on the same way. (In this case it doesn't matter, but it's a good practice anyway.)

Tip: Keep a rag handy. You'll have to up a bit of water when you unhook the copper supply tube.

Some pros prefer to simply replace the valve on old machines to avoid problems in the near future. Look under “Appliance Parts” in your Yellow Pages for sources. Call first.

Tip: Stick the end of the supply tube into a pan and turn on the water supply briefly to flush out sediment before reconnecting the supply tube.

Now run a load of dishes. If the dishes still don't come clean, call in a service expert to find the problem.