Most manufacturers suggest a minimum 120 Fahrenheit for the dishwasher to begin the cleaning process, 140 to remove food soiling, and 155 to sanitize and remove bacteria. In restaurants they boost the dishwasher temperature to 180 Fahrenheit to satisfy health requirements. Consumers misunderstanding these requirements have led to problems for the household dishwasher.
In a dishwasher the temperature of the wash water is paramount. Unfortunately, It is now common to find household water temperatures of only 100 Fahrenheit, or less.
Many people have lowered their household water temperature in an effort to be conscientious consumers. Yes, it lowers electrical consumption. Unfortunately it has other consequences.
Manufacturers say it does not provide enough heat to clean dishes properly and can leave them covered in bacteria and food residue. Supporters of lower water temperatures claim it is both environmentally friendly and necessary to protect children from any possibility of scalding at bath time.
One of the latest ideas is a mixing valve added to hot water tanks. It is preset and will not allow temperatures in excess of 115 Fahrenheit. It does this by mixing cold water with the hot to maintain this preset maximum.
This debate over hot water tank temperatures has resulted in a catch 22 type scenario. Lower the temperature to lower consumption and be more child safe, but end up leaving bacteria on the plates we use to eat.
Low water temperature can also affect the cycle length. If too low the dishwasher may keep stopping to try and heat the water. A normal cycle of 40 minutes could be extended to 2 or 3 hours with all the heating delays. Some dishwashers may stall completely.
Using proper detergent
Gel or crystal, the choice is yours. Both seem to work equally well.
Crystal is less messy, while gel will dissolve quicker with the water. If your water temperature is low (as described above) gel may be a choice because it will mix better.
If using crystal detergent be aware that it can pick up moisture from the air. When this happens it will swell up and become lumpy or harden. These lumps will be difficult to break down and will not fully dissolve. If at cycle's end you see detergent left inside it may be evidence of hardened crystals.
Additional evidence of moisture buildup can be seen if the box itself appears to be swollen. If seen, replace immediately with a fresh box.
A box of detergent should be consumed within 2-3 months. If not throw it away and buy a new one. Match the box size to your needs. Do not buy a large box just because it is on sale. If you have to throw most of it away, it wasn't much of a bargain.
Some detergent manufacturers now offer a product that combines the detergent with the rinse additive. Others offer a detergent that includes a special grease-dissolving agent. Still others are in a tab form, or inside a dissolvable plastic pouch. Whichever form you prefer the one thing we always stress is, "when you find one that works for you stick with it...even if it costs more than others."