Secrets to Make Your Dishwasher Clean Perfectly
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Posted: Saturday, May 14, 2005
by Donald Grummett
As a service company we are constantly asked, "Why doesn't my dishwasher clean better". To this query we offer the following insights and suggestions.
Whenever we diagnose a poor cleaning complaint the main things we want to know are: 1 Is the water hot enough? 2 Are you using a proper detergent? 3 Are you using a rinse additive? 4 Are you using proper loading techniques?
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 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 because of temperature. Others may end up only doing a partial wash.
Due to poor results from their dishwashers some consumers have even returned to washing dishes by hand. They feel using old-fashioned elbow grease is the best way to clean the dishes. In fact studies have shown the opposite. Not only does the dishwasher do a better job, it will use less water. Plus, hand washing means hand drying. A wet dishtowel left exposed to the air is a known breeding ground for bacteria. So if you have returned to this method, always use a freshly laundered dishcloth and dishtowel.
Ever feel that "you can't win for losing".
By "proper" detergent we mean one that you knows has a proven track record. We always suggest using a name brand type that is purchased at a grocery store. Somewhere the turn over is high that you will get a fresh box.
Gel or crystal, the choice is yours. Both seem to work equally well. If you have a preference stick with the type you like.
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.
One caution to be aware of when using crystal detergent is that it can pick up moisture from the air. When this happens it will swell up and become lumpy. Left exposed to air long enough the lumps will harden. If placed into the dishwasher these lumps will be difficult to break down and will not fully dissolve. If at cycle's end you open the door and 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 of normal operation. If the box is not empty after 3 months throw it away and buy a new one. Remember to match the box size to your needs. Do not be tempted to buy a large box just because it is on sale. If you end up having 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".
Dishwashing detergent versus dishwasher detergent
These two detergents are not interchangeable. Trying to do so will cause problems. Each type of detergent is formulated to do a specific job.
"Dishwashing detergent" is the one used to wash dishes in the sink is. It is definitely not meant for the dishwasher. Anyone who has ever mistakenly put it into the dishwasher can attest to the mess this will produce. The beating action of the water will produce massive amounts of suds. This results in the dishwasher flooding out the door and across the kitchen floor.
"Dishwasher detergent" is the one used in the machine. It is very strong compared to the type for hand washing. If used to hand wash it may even burn your skin. Also, it is meant for the harsh spray action of the dishwasher. If you try to use it in the sink it will not mix with the water properly, resulting in poor cleaning.
So the moral of this tale is: "Don't confuse dishwashing with dishwasher".
This is something that gets forgotten once the free sample bottle that came with the dishwasher has been used.
Its job is to make the water run off the dishes faster so they can dry quicker. Without it there would be little beads of water on everything at the end of the cycle. Glasses especially would appear to be water stained or be left with a gritty residue.So if poor cleaning is a problem, check the rinse additive level.
But remember, only one or two drops are added per load. A few ounces of rinse additive lasts a very long time. Such a long time those customers often think it is not being added, and blame the additive for problems it has nothing to do with.
To refill, look on the dishwasher door for a cap or plug that is removable. It is often overlooked because the time between fill ups can be months. Also, the appliance manufacturers could help solve this problem if more of them added some sort of "Hey, I'm empty" indicator.
Frigidaire dishwashers have a neat little indicator. Right next to the soap dispenser is a clear plastic eye that changes colour when the additive is empty. So every time you add detergent to the machine you also see this eye staring back at you. White if empty, and black if full. Simple, effective, and smart.
Lastly, don't forget that how you load the dishes can drastically affect how well they are cleaned.
Proper loading will allow the water to penetrate all the nooks and crannies. Try the following suggestions:
- Cups and glasses on the top rack with bottoms up
- Plates on the bottom rack all facing the same direction
- Bowls either rack, but all facing the same direction
- Utensils in the utensil holder in a mixed fashion (some knives, forks, spoons together in each compartment) to allow gaps between them
- Large items, such as a spatulas, laying down on top rack
- Pots bottom up wherever space allows (on their side okay if positioned so that water will drain out)
Placing the dishes and utensils in an orderly manner really does make for a better wash. It allows the water sprays to penetrate the dishes thoroughly. Try it it works.
The analogy I offer customers is: If you were going on a car trip would you pack the car efficiently, or just open the doors and throw everything inside so that the passengers had to fight with the luggage. I think you get the picture.
You now know what is needed to make the dishes come out of the dishwasher sparkling clean. You require: Hot water, good detergent, rinse additive, and proper loading practices. That's it that's all. Provide all four of these things to the dishwasher and your cleaning success is guaranteed.
So load up the machine, go get yourself a liquid refreshment, put your feet up and let the dishwasher do all the work.
Copyright 2004 by Donald Grummett. All right reserved. Donald Grummett is an appliance service manager in Ottawa, Canada. In the trade over 30 years as both a technician and business owner. For more information about appliances including FAQ, Stain guide, Recycle, and Newsletter visit http://www.mgservices.ca
This Article has been viewed 33,793 times. (Not updated in real-time.)Top-level comments on this article: (7 total)
» left by Angela Carter from Savannah, GA 5 years 313 days ago.
Thank you so much for this article. I have printed it and will post it on my refrig. I have been having trouble with my dishwasher not cleaning the dishes and I am going to do all that you suggest. Again, Thank You!!!
» left by christine from regina, sk, canada 5 years 176 days ago.
Revitting article! Thank you for taking the time to post.
» left by Anonymous 4 years ago.
Excellent article and very helpful for someone trying to buy a dishwasher to meet sanitizing requirements if we want to open a cafe and meet the health codes. Thank you.I only wish that the manufacturers of dishwashers would provide the specs of how hot the heated sanitizing cycle is on each of their products. I have searched product brochures and online manuals from Bosch to Kitchenaid to Frigidaire and no one provides any of this vital information. Why can't they give the information that is so important to someone buying their products?
Everywhere I have lived, it really hasn't seemed worth messing with the dishwasher. You spend almost as much time cleaning the bits of food off your dishes before you put it in as you save by using it. Also, stop using your dishwasher for a month and watch what happens to your electric and water bills. Maybe it's because I've lived in apartments where all we have are the crappy little Kenmore and GEs that you can barely fit a meal's worth of dishes in to...
Very good article though. Lots of information that I'd never seen before, but was very useful.
» left by Bryan from Ontario 3 years 138 days ago.
Answered most of my questions about water temperature but now need to decide between upping temp to 140, (currently at 130), or dropping to 120 and letting the machine heat it. Since most washing is done in middle of night, cycle time isn't too important, and lowering to 125 will allow one to put hands into hot water out of the tap, I'll probably go that route. Maybe you could come and convince my wife that orderly loading is important. I'm staying completely away from that one.
Great job. I don't own one yet, but I hear so many people that complain about their dishwasher that I never really wanted one... Until my pregnant wife started wanting one.I'm going to watch for those things when it's time to buy one.
» left by larry from new jersey 1 year 260 days ago.
If you set the hot water heater to 130 will the dishwasher be able to heat it the rest of the way needed? You mention the temps (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.) but those aren't what the hot water heater has to get them to because the d/w heats it somewhat.... so what is a good temp to set the hwh to so that the d/w can run efficiently?