I have heard of some dishwashers getting louder over time, but usually it is so gradually that you do not notice. It is not like it is going to gain 20dB over time, maybe like 4-6dB over 10 years. Bosch has 3 models lines if dishwashers, Ascenta, Evolution, and Integra. I listed them from the lowest to highest. In each line there are 3 series, 300, 500, and 800, again lowest to highest. The Evolution line is the most popular, and are what most seem rave about. The Integra line is the quietest, relatively speaking, as most Bosch models are quieter than the competition. Miele also makes great dishwashers, but they start over $1000 and go to ~$2300. Asko has some lower models around $800, but I think they have had some leak problems recently. I am not saying all Whirlpool models are bad, just stay away from plastic tub models and go with their SS tub models. But those cost about the same as a nice Bosch, so decide if you need heated dry, and if you do, I would take a good look at some KitchenAid models, most people here like them a lot and they seem better built than most "American" dishwashers.

Would you draw a bathtub full of water, and let all the family member's use the same water? Its the same thing putting dishes in the dishwasher without rinsing them off. Your washing all your dishes in dirty water.... But according to the posts I've read their are a number of factors that contribute to the discussion. It wastes water by rinsing dishes... Well is the water turned on full blast or just at a trickle? The food on the dishes actually helps the detergent work better... Really? Thats like jumping into a mud pit, going inside and taking a shower while trying to lather up with the mud still on you? Does the soap work better? One post read that the dishes sit in the dishwasher for awhile before the dishwasher is ran. So a response was to use the prerinse. Isn't this the same thing as rinsing before they go into the dishwasher? By not prerinsing, food can and will clog into the sprayer jets, eventually. Most people don't know what their hot water heater is set at, and it usually takes a minimum of 125 to start to break down food, and 160 degrees to dissolve food. Not to mention that your dishwasher is usually filled with cold water because the of the draw from the water pipes doesn't heat up in time to get the hot water to the dishwasher. So, in turn if your dishwasher has a heating element, it heats up the water, which is counter productive of the whole reasoning not to rinse your dishes. How many people use the dryer selection to dry their dishes? Or do you just open up the dishwasher and let the dishes air dry? If you use the dryer selection on the dishwasher, You are using as much, if not more, energy then my prerinsing the dishes..... But from what I read, if you aren't using the correct detergent then you've lost the game. Well, if the dishwasher is doing its job, then it shouldn't matter on what kind of detergent you use? Moral of the story, rinse your dishes, check the temp of your hot water heater, prime the hot water before running your dishwasher, let your dishes air dry and you will actually save more energy.

Yep, not pre-rinsing is one of those easy energy/water saving ideas. We have a 5-year-old KA, forget which model. It occasionally leaves stuff on. We also have spousal conflict over loading it- I fit stuff in there tight the same way every time, DW fits about half as much (she eats corn on the cob the same way, a bite here a bite there; I'm all rows). My keys to success: - We use the Electrasol tablets; for big/dirty loads I have a small box of Cascade to put a little in the pre-wash bin so the soap gets on them right away - I generally use the Sani Rinse instead of heat dry, esp. b/c it doesn't bake on anything that's left following the wash (and may knock the last bit of stuff off) - I like the flip down cutlery holders, even though you have to handle the dirty ends of the utensils to load them; they do a great job of getting the utensils all clean and free up the other utensil baskets for spatulas and the like with less crowding. - Depending on how much I'm running and how dirty (esp. if there's a lot of plastic containers, which I worry the most about getting clean), I go from Normal wash to Normal plus hot wash, then to Heavy Duty and hot wash. - We have the top tray, but it gets some use, not every day

Assuming your dishwasher is connected to the household hot water supply, there's no way it can get anything other than hot water ... but how hot is it depends on residual standing water in the line between the water heater and dishwasher. You say that you run the kitchen faucet to a confirmed hot flow before starting the dishwasher, but perhaps the dishwasher is fed from a separate line that's not tapped off the faucet ... or the physical mass of the dishware and dishwasher interior is absorbing much of the heat from the first fill such that the resultant temp in the machine is cool. You'll have to check your user manual for details (if such details are listed there) but a Normal or Heavy cycle usually has two wash periods ... wash, rinse, wash, rinse, rinse for example. A light cycle or sensor cycle that doesn't find much soiling may run only one wash period.