Heated rinse? Heated wash? Both? Neither?

[supersuds]

Speaking of newer dishwashers here, not that I have one, but I've noticed that some give you the option of a heated wash and/or rinse. (Actually, the 1968 Kitchen Aid Superba I grew up with had a Sani-Cycle, but I don't know which cycle it operated on).

I assume that the heated wash gives better cleaning and the hotter water might kill more germs. But if you've done that, why heat the rinse water, also?

And why would you heat the rinse and not the wash?

 

[spankomatic]

Sani-Cycle

As I recall true Sanitization is 180 degree temperature for ? number of minutes. The definition use to be in some of the old dishwasher manuels like in Kitchenaid KDS-18. Anyone have a old manuel? It would make sense to sanitize at the very end when the dishes were cleaned off. The heat also helps drying.

Jim

 

[toggleswitch]

Heating the rinse water helps drying. Especially effective when the drying is not assisted by fan-forced air.

Automatic dishwaers literally kill 100 times more germs than hand washing. The sani-cycle is a mind F--k more than anything. The minute clean dishes are touched, they are no long "sanitary".

Anywhere in New York City apartment buildings there are cockroaches. So don't even let me begin to tell you what manner of vermin is unavoidable. Roach-poop is airborne in New York City and is considerd a normal component of all dust(and triggers asthma attacks). Period.

Killing ADDITIONAL germs in a DW is really not a necessary or desirable goal. It may be just a waste of natural resources (water/chemicals/electricity).

 

[spankomatic]

Hmmm... Now I'm wondering if there is a difference between Sterilization and Sanitization. Anyone?....

 

[toggleswitch]

Sterilization is the attempt to kill ALL germs.
Sanitization is to kill some (large percentage) of germs via a set of standards. Theses may be high temps for a certain duration of time, chemicals etc.

I believe the NSF provides guidelines to be followed by domestic DW manufacturers as to standards to be able to call a load (of dishes and cutlery) "sanitized".

NSF International - Wikipedia

en.wikipedia.org

 

[launderess]

Med/Surg Nursing 101! *LOL*

To sanitise a surface means to reduce bacteria/germ count to a level below a level likely to cause illness.

To sterilize is to basically kill off all living things on a surface. Thus anything that could potentially cause illness is killed off.

You can never make the human skin "sterile", but you can sanitise, hence the long scrubbing in of operating room personnel.

Before modern rinse aids came along the best method for drying dishes was to use heat in the from of a hot air or convection (heating element). With a good rinse aid and water that is decently enough hot, dishes will dry on their own. If the water is very hot to boiling, dishes will "flash" dry very quickly.

Depending upon local code, dishwashers in establishments that serve the public must use either a high temp rinse or chemical agent in the final rinse for sanitising dishes.

Many commercial dishwashers can be set up to keep that final hot rinse water for use in the next following wash cycle.

Consumer Reports has never thought much of "sanitising" dishwasher cycles, poinint out correctly that "germs" will soon be all over dishes once they are touched and put back into the cupboards. Of course there could be some "Hyacinth Buckets" out there who empty their dishwasher wearing sterile gloves and keep their china cabinets scrubbed down clean.

 

[whirlcool]

We use the Sanitize and Hi-Temp wash option on our Maytag DW simply because we put dog food bowls(SS) in there with our dishes. Right before the final rinse the "Heating Delay" light comes on for quite awhile. (10 minutes). The manual says that the Sanitize option meets NSF specifications.

 

[iheartmaytag]

Killing ADDITIONAL germs in a DW is really not a necessary

Well Ok, I will say yes/no to this arguement.
You are correct that the second you touch the dish it is no longer "sanitized" but
Sanitazation is necessary in resturants because humans are filthy. They carry all kinds of things that can be transmitted on utinsles and glasses more than plates, such as Strep, Thrush, Herpes, just to name a few. If an item is improperly washed germs can be spred to others quite rapidly.

In a home or daycare setting the use of the sani cycle can be justified by stopping the spread from one family member to another. Though I do agree with you that the little bugs that are able to withstand 120 degree water with harsh alkali detergent deserves to live, but the added boost of 157 to 180 degree water just makes me feel better. This should not be a substitute for other hygenic practices such as washing the cabinets and counters with my old time friend--Bleach. Also remembering to wash one's hands often is the best way to prevent the spread of infections.

Now as for roaches, I would have "Billy the Exterminator" at my house so fast and he could have the guest room if he wanted to stay and make sure the little buggers didn't return.

[this post was last edited: 8/5/2010-09:55]

 

[frigilux]

I've been using the 160-degree rinse more often. It only takes a few extra minutes in my LG and everything dries better. Using the sani-rinse on my previous dishwashers (Maytag and Frigidaire) added about 20 minutes to the cycle. Not so with the LG.

But come to think of it, I believe those machines heated to 150 or 155-degrees, so maybe they needed to hold the cycle at that temp longer than the LG, which heats to 160.

There's also less water in the tub with the LG, so it doesn't take as long to hit the target temp.

 

[passatdoc]

My nine year old Bosch 300 series has three cycles: Quick Wash, Normal, and Powerscrub Plus. Normal has a final rinse of c. 140 F and is NSF-certified. Powerscrub Plus has final rinse of c. 160 F and also is NSF-certified.

Quick Wash is not NSF-certified and final rinse is c. 106 F. However, it does a complete cycle in 30 minutes and will work if dishes are pre-rinsed. I have used it when having large numbers of company for say coffee and cake where dishes/cups/glasses are lightly soiled. In a pinch, one could use this when entertaining for a full meal, but everything would have to be pre-rinsed thoroughly. Quite possibly some of the "quick" or "party" cycles on newer models (mine is entry level Bosch from 2000) do a better job on the short cycle.

Per the user's manual, the heater engages any time the incoming hot water falls short of the specified wash or rinse temp. My hot water is probably 130 F at the tap, so most likely my DW heater goes into action for Normal and PowerScrub cycles. In that sense, it's a "heated rinse". For Quick Wash, most likely the final rinse occurs at the ambient water line temp, with the heater kicking in only if the temp drops below 106 F. I.e, the heater doesn't engage for Quick Wash under normal circumstances, but the incoming hot water is obviously higher than 106 F.

 

[supersuds]

I was under the impression that the average dishwasher would heat wash water to 140 degrees. That seems like enough. But 106 seems pretty cool...

 

[lavamat_jon]

The theory, at least on European dishwashers, is that the heated wash kills the germs (it's not a coincidence that pretty much most "normal" cycles are at least 65*C, which is the point in general at which most household germs are killed), and the heated rinse is to aid in the following condensation drying process. That and I imagine a higher rinse temperature probably enhances the rinse aid action too on the final rinse of Euro d/ws.

Jon

 

[passatdoc]

I rarely use the Quick Wash cycle. When I do use it, it's often for tall items that aren't dishes or glasses, with the top rack removed and the tall item sprinkler attachment in place. Examples: Wolford lamps (blown glass oil lamps), baking pans, etc. These don't need to be sanitized and probably the lower temp is better for these non-stainless or porcelain products. I doubt if the wash or rinse temp is really as low as 106 F---it's probably whatever the incoming hot water temp happens to be (130 F or so), but the temp doesn't get a heated boost by the DW above ambient hot water temp. The 106 F is probably a minimum, so that IF incoming hot water were below 106 F (say, if someone was taking a shower and washing a load of clothes all at once, with a storage type heater), the heater might then kick in and boost the temperature....however the cycle time of 30 minutes would have to lengthen in order to allow for water heating time.

Some upscale manufacturers like Miele offer a 30 minute "Party" cycle for people who do a lot of entertaining and who have "only" one DW. However, before buying into this concept, one would have to check the rinse temp. The 30 minute cycle on my Bosch (built 2000) is only 106 F, so it's possible that these quick cycles may not meet NSF standards. (but as above, my Quick cycle probably runs at 130 F, not 106 F, since my hot water line is about 130 F).

Most normal loads come out perfectly clean with Normal cycle. I sometimes use PowerScrub Plus but only for heavily soiled loads. I usually prepare hot oatmeal for breakfast (with fruit) and I just throw the oatmeal bowls with dried-on oatmeal into the top rack of the Bosch, no rinsing or scraping. I might go 4-5 days between loads, and everything comes out sparkling clean.

 

[passatdoc]

second dishwasher

Before the economy tanked, the NY Times had an article about second dishwashers. Typically these were installed by people either building new or doing a complete (demolition) remodel. The article's point was that with the rising cost of base cabinets, adding a second MOL dishwasher in a medium or medium-large kitchen was not much more expensive (because you skip the cost of the base cabinet), and was useful for those who entertained often or on a large scale, say frequent dinners for 8-12.

Quite often the second dishwasher was an entry level model (vs. the full featured primary DW) and often situated near the pantry, with an auxiliary sink nearby (often with a disposal) so that a friend or employee could help out after dinner by rinsing and loading the DW, which was located near the pantry storage for glassware/dishware/stainless steel.

Prior to this trend, the main times you'd see two dishwashers would be in very large estates, or in homes of devout Jews who keep the Kosher dietary laws (requiring separate sets of dishes/utensils/cookware for milk and meat products).

 

[lordkenmore]

"Prior to this trend, the main times you'd see two dishwashers would be in very large estates, or in homes of devout Jews who keep the Kosher dietary laws (requiring separate sets of dishes/utensils/cookware for milk and meat products)."

And don't forget the homes of appliance collectors, who might not stop at a mere 2 dishwashers!

 

[DADoES]

 
Regards to the question of heated rinse, wash, or both ... my answer is both.  DishDrawers always heat the main wash & final rinse to specific target temps per the selected cycle, assuming the household water supply hasn't already heated the temp sensor sufficiently.  It's an assured heating system, meaning the cycle is always delayed as long as needed to reach the target.  Normal cycle hits 140°F for wash, 150°F for rinse.  Heavy is 150°F wash, 163°F rinse.  Lowest temp is 105°F for wash & rinse on the Fast/Eco cycle.

 

[jerrod6]

Growing up my parents had at 1971 KA superba. I remember it was a great machine. After their death I sold the house and kept the user manual but it doesn't give me the model number just the name and pictures. Now I know I should have taken that DW with me.

I checked the manual and the difference between the sani cycle and full cycle was that the last rinse water was heated to 180F. The timing chart says that the cycle lasted 4 minutes 8 seconds, plus the time it took to heat the water to 180F. It would pause to do the heating. This timing chart shows the times for each part of the cycle. Rinses 3 minutes 6 seconds, the main wash 8 minutes 4 seconds, the dry 22 minutes and 8 seconds.

My Dw today has some cycles that vary the water temperature according to the soil level so when using them you don't always get the same temperature each time. Some of the washes are kept below 130F for glass care. I checked a few washes and they where about 125F some where 128F, some where 120F. One time I ran the normal cycle and it was 117F.

It has a sani cycle. I've used it 1 time. It heats the last rinse water to 167F and rinses for quite a while at this temp. However pots and pans and the starch cycle have washes that use higher temps,so I don't use sani cycle that much.

Most of the final rinses are at 150F but there are a few cycles where the final rinse seems to be at 130F.

There are two programs(cheese and starch) that heat the prewash but I am not sure what temperature the water is heated to but it is steamy. The interim rinses are unheated and rely on the temperature of the water entering the machine which in the winter my machine is going to get almost cold water.

 

[logixx]

Our Euro Siemens heats both the pre- and main wash step when using either the auto Normal or auto Heavy cycle - unless the pre-wash step is skipped, of course. The Eco cycle pre-rinses with cold water. Using the Extra Dry function raises the final rinse from 149F to 158F, which adds five minutes to the cycle.

Quick Wash does well even on pots - if the soil hasn't dried on. The final rinse is 131F with Extra Dry. When you open the door at the end of the Quick cycle, dishes flash dry within 30 seconds. I tried the Quick cycle on a Miele before and was disappointed when everything was still pretty wet when I opened the door. Maybe because of the 113F final rinse...

Alex

 

[passatdoc]

Agree, Logixx

My Quick Wash with 106 F final rinse (2000 Bosch 300 series) isn't going to flash dry the dishes if you are entertaining and need to reload the DW in a hurry with a second set of dishes. However, as a water/energy saver on lightly soiled loads, it's ok.

Prior to owning a Bosch, I was dependent on Rinse/Hold cycles, both in the KA I grew up with and with the last DW (a MOL GE PotScrubber) before the Bosch. Neither of these machines, not even the KA (1961 model Superba) could handle dried-on food, so we used Rinse-Hold whenever the machine wasn't full enough to run a normal wash cycle. Basically, if you didn't have a full DW, you at least ran Rinse/Hold before the end of the day.

When I bought my Bosch, I did so sight unseen, because they had been released to the market only a week before: the then-new Integra Design with controls in the door edge. Bosch already offered the Integra TOL series with door-edge controls, but now they were extending the same design to their BOL and MOL models, called Integra Design. According to the sales manual, I thought I was ordering a machine with Rinse/Hold, Normal, and PowerScrub Plus. When it arrived, I was somewhat disappointed: it had Quick Wash, Normal, and PowerScrub Plus. Turns out there were TWO models in the 300 series, differing mainly as to whether the third cycle was Quick Wash or Rinse/Hold. The retailer said if I didn't like Quick Wash, they would swap it out with a model with Rinse/Hold (the source of the error was the dealer manual, which showed only one 300 model, with Rinse/Hold, but did not show the second model with Quick Wash)

Once I discovered how much better the Bosch cleans, in particular its ability to handle dried on food several days old, I began to realize that Rinse/Hold wasn't necessary like in the old days, and that Quick Wash had some usefulness. Less so to handle actual soiled dishes and more so to handle household items (vases, fine glassware, tall items, baking pans) that don't need to be sanitized and which are not usually placed heavily soiled in the DW. Quite possibly the reason Quick Wash seems to work fairly well for me (for light soil) is that my water heater is just on the other side of the wall from the DW and the incoming hot water is about 130 F, so I doubt if the final rinse is ever anywhere nearly as low as 106 F.