some people do it but it is not necessary. The DW heats up the water anyway.

Sooner or later you will have to know your model number, so now is a good time to post again and let it be known.

-david

They recommend running the water in my manual but I never bother - my dishes come out sparkling clean and dry in my 6 year old KA. I use Cascade Complete and Jet Dry, ususally I use the Normal cycle with Sani-risne and everything works fine. I've never ever used 4-hour delay, not sure why I would since the DW is so quiet.

Thanks for your responses. My model is the KUDT03. I like you "weissman" use Cascade Complete and Jet Dry. I have even added lemi-shine. Often times my dishes are not that clean and/or have a film on the glasses etc when I go to empty the dishwasher. I did have a plumber out at one point to check on my water heater etc. because when I opened the dishwasher early on and the water was luke warm at best. He couldn't find anything wrong other than the fact that our water takes a while to get warm at the tap. I'm thinking my dishwasher is just not right and hasn't been from the get go.

One more thing to check - do you have a high loop in the drain hose and/or an air gap - it's possible that you have dirty water backing up into the dishwasher.

even though my asko has a heater in it, i run the water so that it is hot.
we found that electrasol works best with the asko. the dishwasher is very quiet and cleans very well.

Set an alarm (does your cell phone have an alarm clock?) to 3 hours and 55 minutes from the time you set your 4 hour DW timer. When it goes off, run the hot water for a while.

Ok, don't shoot me for my wise-ass response. But nowhere in this thread do I see that your dishwasher in fact works better when the water supply is fresh and hot. Does it?

We have a 9 month old KUDSO3 and the dishes come out just fine. I use Cascade Complete but honestly prefer Electra-sol
tabs, which I think do a better job and don't smell like fake lemon.

If your dw is under warranty, you should have it checked again and save some of those dirty dishes for the service person to look at. How old is your machine?

Pharaoh,
You don't need to run the water first. Your Asko will heat the water to the desired temperature for each wash and rinse cycle.

Rock,
Do you have hard water? DId you have another DW before and did it clean your dishes? Have you run a DW cleaner through your system and see if there is an improvement? Do you pre-rinse your dishes before washing them?

I don't run the water before using my dishwasher. I have a Miele and it works flawlessly.

I thought I was the only one who was sensitive to the smells of these Dishwashing detergents. I buy the Miele DW tabs because I can't stand the smell of the Electrasol and Cascade. I have not seen an unscented Electrasol anywhere since they changed to Finish. Rant over!!

Running hot water before will almost always lead to high temps inside dishwasher during the cycle. Each brand of dishwasher works differently and it effects how they will react to cold water on the tap.

For instance, DD use lower volumes of water and heat well but the cycle will run longer (and waste energy) if the water comes in cold.

I expect that average dishwasher does not adjust cycle length and has a heater that can't adequately heat water fast enough to make up for the cold incoming water.

The most obvious thing to do is stop using the timer and run the hot water each time. See if that makes a difference. Comparing to other people is problematic because their water might be softer, their hot water heater might be closer, their cycles might be designed differently. Homepro1 has a Miele which probably is designed to handle cold water (since it is European) and your Kitchenaid most likely is not.

For instance, DD use lower volumes of water and heat well but the cycle will run longer (and waste energy) if the water comes in cold.I assume "DD" refers to Fisher & Paykel DishDrawers. I have to disagree with your statement. My DD603 can raise the water temp by between 1.5°F and 2°F per minute. I've not found that running it with cold water increases cycle time by an appreciable/objectionable amount. As for wasting energy ... I checked it several months ago with a Kill-a-Watt meter. The heaviest cycle (targets 150°F for the main wash, 163°F for the final rinse) used 0.68 KWH of power with my household tankless water heat set low so it didn't run. At my electric rate of about 12 cents per KWH, it used about 8 cents worth of power in a 132-minute cycle ... and that's with using NO energy in regards to the household hot water supply.

This is good information. Good for a second reason, because it is hardly ever measured and published (posted).

"Raising H2O temperature" is a subject that causes a lot of people to take mental shortcuts and draw erroneous conclusions. They often neglect to consider that HW has to be created somewhere at some place in their whole house or whole system. HW tanks holding HW have a cost, which includes both the cost of raising the water temperature (the same for all heaters big or small, close at hand or far away) and also standby costs due to raising the water temperature and holding_it_as_HW, thereby paying to keep it hot since its heat leaks out and warms up the surroundings (e.g. the floor under it).

Thank you dadoes.

About the "average dishwasher" not adjusting its cycle length and having "a heater that can't adequately heat water fast enough to make up for the cold incoming water" I would say the exact opposite, without any proof at all except anecdotal hearings. To me it makes sense that aDW with an inline heater would have a switch activated when temperature is reached instead of a time-based switch. So, like, I'd expect, Duh, the opposite, if we are going to just write out what we expect based on no_information at all.

In a few years from now we'll know more, if people measure their Bosch anf other machines' times. After the machine has drawn water once, HW is already in the pipe now, so only the initial fill up will be shorter in time.

HTH
-david

Huh...?????

I think more than one "huh?" is warranted here.

"My DD603 can raise the water temp by between 1.5°F and 2°F per minute. I've not found that running it with cold water increases cycle time by an appreciable/objectionable amount."

Dadoes - Assuming your cold tap water is around 55 deg and your hot tap water is around 120, then based on what you're saying you'd be adding over 30 minutes to each heated portion of the cycle. Where's my logic off?

David - On their web site Kitchenaid makes a point of advertising that their DWs adjust cycle time based on conditions including incoming water temp. User manual states the same. So I'm guessing that this isn't standard in an "average dishwasher" but who knows, who cares. More importantly, the installation manual calls for 120 deg water input and does not give a cold water hookup option as do some other brands/models. This would lead me to doubt that the DW is designed to overcome completely cold water.

But I'll defer back to my prior post. All this is useless babble until we know whether running the sink before the cycle actually helps the OP get clean dishes. If the answer is no, then clearly there are more important areas to explore.

I always run my water before starting the DW. I want the first rinse to be with hot, not cold water. Not to mention subsequent refills of the tub. And I don't use the time delay for this reason.

As opposed to the cloths washer which is much closer to the hot water tank. It getting hot water while filling is much less of a problem due to the short water run.

ya_think,

1) My hot tap water is not 120°F. I run my tankless water heater at 105°F. Being that the distance from it to my kitchen is fairly long plumbing-wise, and the DD pulls only 0.8 gals per fill, it runs on "cold" water anyway unless I prime the faucet first (which I rarely do). I checked just now ... after running about 2.5 gals through, the temp was a whopping 96°F.

2) I did the tests in August & September. My tap water is not 55°F at that time of year. Maybe 75°F to 80°F. Sure, lower water temps take more time ... but ...

3) Cycle times are long enough by default that the additional time needed for heating colder water is negligible. The Heavy cycle estimates at 132 mins. Of that, about 28 mins is dry. So that leaves ~104 mins for 7 water changes, wash/rinse sequences. Two of the 7 are the main wash and final rinse targeted to specific temps. Estimating the 5 other wash/rinse sequences plus drain periods at 6 mins each, that leaves 74 mins. Dividing equally, that's 37 mins each for main wash and final rinse. Assuming linear calculations, at a temp rise of 2°F per min, that's a 74°F temp rinse for each at standard cycle time. 55°F + 74°F = 129°F. Additional time to reach 150°F and 163°F: 11 mins and 17 mins. In practice I think it's a little less difference total. And being that I don't hover over the machine while it runs, waiting for it to finish, it's of no consequence either way.

BTW, DishDrawers have a delay function of up to 12 hrs. I used it once that I can recall.

dadoes - I follow your logic, thanks for the explanation. But based on what you're saying, basically your machine spends all that time to get up to temp only to then dump the hot water. This, as opposed to getting up to temp quickly and then using that hot water for a good portion of the cycle. Maybe it doesn't make a difference, after all you're not complaining about dirty dishes. Interesting. As a matter of interest, are you a "rinser" or a "scraper"?

Scrape only.

Being that is sprays the entire time it's heating, the dishes are washed plenty well.

Back to energy considerations. My hot water heat is with gas, the DD (yes F&P) heat with electricity. So - anyone want to claim that electricity (using resistance heating) is as efficient as gas?

But the point is well taken that this is not a lot of $$ - but remember some people live in CA and pay up to $.30 per KWH. Add this to running 3 DDs a day (what I suspect at average family to do) - and you get up to $.60 a day. Now probably only $.20 can be saved but that is still $70 a year. And this is with Dadoes incredibly high tap temps.

Now - if you had the typical water usage for a dishwasher - which I am guessing is 5x a DD - then you can add up to serious $$. Now I standby my assertion that average dishwaher does not extend the cycle enough to get water hot enough.

I just checked an average GE dishwasher troubleshoting guide. The first thing to check under "dishes not getting clean" is the water inlet temperature. It recommends running the hot water line first as a fix. So GE clearly thinks that inlet temperature matters ... a lot.

I use the 4 hour delay (or two or eight, depending on my needs). When I do a load immediately, I do run the water till it's hot. I had the same problem, things just didn't seem clean so now I always run a high temp scrub, which heats the water even more. There was an article late last year in some paper that recommended using the high temp setting, and they are right, it really helps. I use Cascade Complete - and that seems to help, too.

I think, in the "old days" we rinsed our dishes more, so there wasn't much to clean. Now, with rinsing not needed (though scraping is), we have to wash differently, with hotter water and a longer cycle.

I use the 4 hour delay for an issue unrelated to dishwashing. I live alone and don't use a lot of hot water. I have an oil water heater with a 20 degree swing in temp - right now the max temp is about 135 degrees so the minimum temp is about 115 degrees - barely warm enough for a shower (trust me). When I shower, I never know if the water is going to be merely warm, or actually hot, so on the nights I run the dishwasher, I set it to run early in the morning so it pulls enough water out of the water heater to trigger the burner, that way I have hot water for my shower when I get up.

... so the minimum temp is about 115 degrees - barely warm enough for a shower (trust me).Huh? Barely warm enough? I shower at 102°F to 105°F, and that's way plenty warm! Are you really standing under a stream of 115°F water and finding it chilly?
Add this to running 3 DDs a day (what I suspect at average family to do)... That seems a bit much. And every load doesn't have to be run on the Heavy cycle. Normal Eco does a fine job on many loads. The latest enzyme detergent formulations work nicely at lower temperatures coupled with the longer cycles that many dishwashers do nowadays. I have a friend has one of the new Kenmore HE dishwashers. He says the temp may be low as 118°F during the main wash period, but coupled with a sufficiently long wash as controlled the soil-sensing computer, it does a wonderful job.

Anyways ... back to the original question. If your dishwasher isn't doing very well, check the temperature of the water at your tap, run it to hot before starting the machine. Raise your water heater setting if necessary. If that doesn't help, then water temperature likely isn't the specific problem. Try running a dose of dishwasher cleaner (JetDry brand or LemiShine), or run a cycle with no dishes and toss in a couple cups of vinegar.

As for using the delay function, let experience be your guide. Use the delay without running the tap. If the dishes are clean, wonderful. If not, and they are clean when NOT using the delay AND running the faucet to hot, then you'll know not to do that again. An inconvenience, but not exactly a tragedy.

But if you do run the water in the tap to get the first fill of the DW with HOT water, what about the other "fills"? A significant amount of time goes by when the DW is washing and by the time it's ready for a rinse, hasn't the water in the pipe already cooled down thus having to purge the cool water AGAIN?

here is a new suggestion for you. I have a 8 year old KA dw. In the beginning, I was having so much trouble with it, mostly gritty substance on my glasses. Had service out MANY times. Use more soap, less soap.... I even had one guy tell me I must have hard water (I get my water from the city of Detroit -- it is not hard!!).

Anyhow, I ran DISHWASHER MAGIC through my machine and it was 100% better. You buy it at any hardware store and it costs about $3-$4. Every once in while, I'll get bad results again and I use DM again to fix it.

Also, I recently started using Cascade Actionpacs -- they are awesome! It got stains out of plastic cups that have been there for years!