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2 Strikes & the Dishwasher’s Not Out

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William K.
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Platinum
A similar problem with the whirlpool dryers
William K.   6/11/2013 8:12:57 AM
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Maytag is not the only company to cut a corner on squirrl cage blower designs. Our whirlpool dryer, and the one belonging to a friend, also developed the rubbing blower syndrome, but the fix was not that easy. It seems that the main blower is only connected to the drive shaft by a rather weak spring clamp, with no means of positive attachment. But the blower is not perfectly balanced, and not immune to the accumulation of a bit of lint, since it is downstream from the drying clothes. What happens is that the blower wheel vibrates just a bit on the shaft, which the atachment is a split hub made of the same nylon-type of material. The result is that there is wear, resulting in greater clearance, resulting in greater vibration. Eventually the wear will reach the point that the blower wheel no longer engages the shaft, and so it does not spin, resultingin no airflow, which leads to an overheating condition, which causes the non-resettable overtemperature device to open, leaving the system non-functional. The only repair is replacing the blower wheel and the overtemp protection device, which are accessed from opposite acess points on the dryer. But that does not eliminate the problem with the drive connecton to the blower wheel, which the replacement is not improved from the original design. The (sort of) fix is adding a screw type hose clamp in place of the weaker spring clamp, although a real fix would be a solid hub, close fitting, and a different design to keep it on the shaft, such as a bolt in the end of the shaft and a cup-washer to clamp the hub. BUT of course that would mean changing the design and adding a production step or two. Better quality does cost more to build, it seems.

Rob Spiegel
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Blogger
Re: A similar problem with the whirlpool dryers
Rob Spiegel   6/11/2013 1:40:35 PM
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William K, I'd love to use this as a Monkey blog. Please send along your OK to:

rob.spiegel@ubm.com

Cabe Atwell
User Rank
Blogger
Re: A similar problem with the whirlpool dryers
Cabe Atwell   6/11/2013 5:23:45 PM
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Geez,

Seems like it was designed to fail. Then, resulting in further sales down the line.

Serviceable features need to be accessible. It's 2013 already...

C

RBPrice
User Rank
Iron
Re: A similar problem with the whirlpool dryers
RBPrice   6/11/2013 9:07:49 PM
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Not qute designed to fail but it sure is hard to not be paranoid about the failure to tell the user that there was a filter that had to be serviced periodically so some repair person could charge an outrageous sum for a trivial service operation. 

That is an evil monkey at work not a dumb monkey like the second issue with the blower.

William K.
User Rank
Platinum
Re: A similar problem with the whirlpool dryers
William K.   6/11/2013 11:52:09 PM
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Not letting folks know about the filter changing requirement is the one way that they have of keeping those totally unqualified fingers out. And there are a lot of folks so inept that they cross-thread lightbulbs. Of course, some companies go way overboard, like the five-point anti-tamper screws on a seagate external hard drive. They were a pain to remove, but I did remove them and replaced the failed hard drive. Possibly some of it comes from a desire to avoid litigation for somebody injuring themselves, inept people do that a lot.

But on that dishwasher, the well designed ones use a different system to avoid the need for filter cleaning. And some of the other good ones make the filter easy to find. That may be part of the difference between an older expensive unit and a current cheap one.

RBPrice
User Rank
Iron
Re: A similar problem with the whirlpool dryers
RBPrice   6/12/2013 7:48:07 AM
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True enuf about keeping inept people from hurting themselves but how about at least warning to the owner that the filter needs to be serviced periodically.  That monkey mind set is not a good way to build customer satisfaction and loyalty. 

Adding a small boss on the end of a molded nylon squirrel cage rotor is not a very expensive thing to do. The material cost is close to zero and the cost to machine the recess in the mold is divided by 50,000+ parts.

What it really boils down to is the mindset of the company management and their focus on quarterly earnings instead of long term sales based on a quality product. I have, unfortunately, seen it at several companies that I have either worked for or done consulting work for.

Rob Spiegel
User Rank
Blogger
Re: A similar problem with the whirlpool dryers
Rob Spiegel   6/12/2013 1:26:34 PM
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I agree Cabe, but as big box appliances add more electronics, they seem to lose dependability. Time after time, our Monkey writers regret having given up their mechanical washers, dishwashers and dryers.

William K.
User Rank
Platinum
Re: A similar problem with the whirlpool dryers
William K.   6/11/2013 11:54:00 PM
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I will send an email about that in the next two days, Rob.

Larry M
User Rank
Platinum
Re: A similar problem with the whirlpool dryers
Larry M   6/12/2013 9:42:39 AM
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I might have used one of those spring-type hose clamps instead of a worm clamp to hold the rotor on the shaft, since it would seem to have less effect on balance.

And I might have used a pop-rivet on the fan cover if I didn't have a shorter screw.

William K.
User Rank
Platinum
Re: A similar problem with the whirlpool dryers
William K.   6/13/2013 9:46:52 PM
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Larry M, the spring clamp is the source of the problem, since the spring allows movement, which causes the wear. And at 1750 RPM the small unbalance of the worm style clamp is not a big deal. But if it were, it would be a simple matter to use two of them so as to maintain balance.

I had a dishwasher that somehow had the drain age flow clean the food filter, so that the filter did not normally need to be manually cleaned. If a dishwasher manual indicated that dishes had to be cleaned prior to washing, I would consider that a deffective design and retuyrn the machine and demand a refund. A machine that is unable to do the job that it is made for is JUNK.

Larry M
User Rank
Platinum
Re: A similar problem with the whirlpool dryers
Larry M   6/14/2013 10:00:28 AM
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William K, I was thinking of those really serious clamps that work best with a special hose clamp pliers, like one of these clamps:

http://www.hcl-clamping.com/images/product_pics/l-double-wire-spring.jpg

http://www.amazonsupply.com/rotor-clip-hc-4st-steel-single/dp/B005EMZZN6

http://www.gasgoo.com/auto-products/fastener-452/1226129.html

Even the smallest of these can clamp with substantial force if made from the right steel/

William K.
User Rank
Platinum
Re: A similar problem with the whirlpool dryers
William K.   6/15/2013 6:51:02 PM
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Larry, all of those clamps are spring clamps, and besides that they all apply the clamping force along a single line, at least the wire ones do. The third link shows a clamp similar to what is provided with the blower wheel, and that one does allow the very slight motion that causes the wear. The worm gear style clamps don't have any compliance, they wind up being rigid, and so allow no motion. The whole problem is that there is a very small movement that leads to wear, which loosens the joint, leading to more motion and more wear. 

In addition, a spring wire clamp that was tight enough to prevent all relative motion would probably exceed the allowable surface loading of the material.

Reuven
User Rank
Bronze
Re: A similar problem with the whirlpool dryers
Reuven   6/12/2013 1:50:21 PM
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I have written several times about this very problem.  I have a Kenmore washer, with no mention of a filter, and Kenmore freezer with no mention of a backup 9v battery.  I had a Bowlens electric lawnmower with no mention of a design feature that would trap grass and cause the motor to overheat.  Not only was there no mention of this problem, there was no nondestructive way to clean it out.  The lawnmower problem was discovered when I did a teardown on the machine.  The Kenmore problems were solved by doing research on the internet and finding information from other owners who shared their stories.

GTOlover
User Rank
Platinum
In defense of Maytag
GTOlover   6/12/2013 10:56:02 AM
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I am only defending the filter design and not the bearing issue!

I have had a maytag dishwasher (and other brands) and most all of them suggest rinsing the dishes prior to loading into the machine. But, I just load them into the dishwasher with all the clumps of food stuff, ketchup piles, and corn kernels still on the plates. I even throw in the mashed potato spoon still full of junk! Knowing this, the manufactures have to filter the pump (which is usually a screen on the floor of the unit). But even this can suck those mashed potatos into the system. One thing that seems to be constant is the wash arms are two piece designs glued together. Thus, the better manufactures make sure to filter this part to prevent the holes from clogging up. The Whirlpool dishwasher I currently have does not and the wash arms got plugged up. To fix them I had to purchase new ones. Now I take them out about every 6 months and thourghly clean them out!

So (and this is only a guess on my part) I think Maytag may actually have been trying to prevent the spray arms from clogging up. But why they do not mention this filter in the manual is monkey material!

rkinner
User Rank
Iron
Re: In defense of Maytag
rkinner   6/18/2013 4:55:25 PM
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I too have a dishwasher (10 years old) the slowly got worse in cleaning the dishes.  I tracked it down to the last hole in the lower swing arm being clogged (both ends).  This last hole was angled so it would push the swing arm around to clean most every part of the compartment. 

I ended up finding the smallest tweezers I could to reach in to the hole and pull out the food that was stuck inside.  I do that every few months to keep the unit cleaning fairly well.  It is down stream of the filter (and that is clean) but small parts accumulate at the end of the arm, probably from centrifugal force.  Once it cakes up the arm just stays in on e spot for the whole cycle.

Tom-R
User Rank
Gold
Re: In defense of Maytag
Tom-R   6/25/2013 10:47:21 AM
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I suspect the filter plugging on a 19 year old dish washer is due to the environmental changes made in dishwasher detergent, and not a monkey at Maytag. The detergents are now all phosphate free, thanks to a few States implementing regulations a few years ago. It fits the timing well. The problem with the new detergents is that a film forms that won't wash off many surfaces of your dishwasher. That probably plugged the filter. Before that the filter would have flushed clean every time the washer drained. Now you have to run some TSP through the washer, or buy one of the special dishwasher cleaning solutions being sold by the same detergent companies. Does anyone else see the irony of having to run a special wash solution through a washer to keep it clean?

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