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Troubleshooting

Spots and stains on dishes

• Spotting and filming on dishes

Is your water hard, or is there a high mineral content in your water? Conditioning the final rinse water with a liquid rinse aid helps eliminate spotting and filming. Keep the rinse aid dispenser filled. Always use a high-temp option. Is the water temperature too low? For best dishwashing results, water should be 120°F (49°C) as it enters the dishwasher. Did you use the correct amount of effective detergent? Use recommended dishwasher detergents only. Do not use less than 1 tbs (15 g) per load. Detergent must be fresh to be effective. Heavy soil and/or hard water generally require extra detergent.

• Silica film or etching (silica film is a milky, rainbow-colored deposit; etching is a cloudy film)

Sometimes there is a water/chemical reaction with certain types of glassware. This is usually caused by some combination of soft or softened water, alkaline washing solutions, insufficient rinsing, overloading the dishwasher, and the heat of drying. It might not be possible to avoid the problem, except by hand washing. To slow this process use a minimum amount of detergent but not less than 1 tbs (15 g) per load. Use a liquid rinse aid and underload the dishwasher to allow thorough rinsing. Silica film and etching are permanent and cannot be removed.

• White spots on cookware with nonstick finish

Has the dishwasher detergent removed cookware seasoning? Reseason cookware after washing it in the dishwasher.

• Brown stains on dishes and dishwasher interior

Does your water have high iron content? Rewash dishes using 1-3 tsp (5-15 mL) of citric acid crystals added to the main wash section of the detergent dispenser. Do not use detergent. Follow with a Normal wash cycle with detergent. If treatment is needed more often than every other month, the installation of an iron removal unit is recommended.

• Black or gray marks on dishes

Are aluminum items rubbing dishes during washing? Disposable aluminum items can break down in the dishwasher and cause marking. Hand wash these items. Remove aluminum markings by using a mild abrasive cleaner.

• Orange stains on plastic dishes or dishwasher interior

Are large amounts of tomato-based foods on dishes placed in the dishwasher? It may be necessary to use a stain removal product to remove stains from your dishwasher. Stains will not affect dishwasher performance

Dishes are not completely clean

• Food soil left on the dishes

Is the dishwasher loaded correctly? Can the spray arm rotate freely? Did you choose the cycle that describes the most difficult soil in your dishwasher? If you have some items with heavier soils, use a heavier cycle. Did you use the correct amount of fresh detergent? Use recommended dishwasher detergents only. Do not use less than 1 tbs (15 g) per load. Detergent must be fresh to be effective. Heavy soil and/or hard water generally require extra detergent. Is detergent still in the detergent cup? Use fresh detergent only. Do not block the detergent dispenser. Is the water temperature too low? For best dishwashing results, water should be 120°F (49°C) as it enters the dishwasher.

Dish Washer Care

Cleaning the Dishwasher

Clean the exterior of the dishwasher with a soft, damp cloth and mild detergent. If your dishwasher has a stainless steel exterior, a stainless steel cleaner is recommended.

NOTE: Do not clean the dishwasher interior until it has cooled.

Clean the interior of the dishwasher, with a paste of powdered dishwasher detergent and water or use liquid dishwasher detergent on a damp sponge to clean the cooled-down interior. A white vinegar rinse may remove white spots and film. Vinegar is an acid, and using it too often could damage your dishwasher. Put 2 cups (500 mL) white vinegar in a glass or dishwasher-safe measuring cup on the bottom rack. Run the dishwasher through a complete washing cycle using an air-dry or an energy-saving dry option. Do not use detergent. Vinegar will mix with the wash water

Periodically clean the coarse filter cup located on the floor of the dishwasher drawer. Remove collected particles from the coarse filter cup.

IMPORTANT: Do not start the dishwasher until the coarse filter cup is securely in place and flush with the coarse filter plate. Doing so may damage the dishwasher motor and/or spray arm.

Cleaning the Coarse Filter Cup

1. Pull drawer out to its full extension. Remove rack inserts from rack and set aside.
2. To remove the coarse filter cup, unscrew the small cap, turning in a counterclockwise motion. Lift and remove the coarse filter cup out of the drawer.
3. Empty the cup of hard objects and food soil. Rinse cup under hot water.
4. Place the coarse filter cup back into the coarse filter plate and tighten the cap, turning in a clockwise motion. Make sure the coarse filter cup is flush with the coarse filter plate.
5. Replace the rack inserts.
6. Make sure spray arm rotates freely

If you have a drain air gap, check and clean it if the dishwasher isn't draining well.

Have you tried all of this?

Is the dishwasher draining properly?

You might want to make a call to technical support, or a local appliance repair person.

I have had my Bosch dishwasher for about a year using the same setup you contemplate, so I'm familiar with the exact drain connector you have on the dishwasher hose. On mine, there was something of a taper between the 1/2 and 3/4 section and being rather flexible rubber, and I had no difficulty stretching the 1/2 section of the fitting to fit on the 5/8 gap fitting. I then tightened down the hose clamp with a hex bit on my cordless driver. The clamp was tight enough to somewhat compress a groove into the rubber, and I tugged on the thing as hard as I could. It isn't coming off IMHO. I'm at work, but can send a picture later if you need.

I understand you are worried somewhat about the quality of the connection. You could get a 1/2 to 5/8 adapter like this:

But that would entail 3 hose clamps and a section of 5/8 ID hose to connect between the adapter and air gap. That seems like more points of failure. At any rate, I think you already have what you need to get this working.