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Cadman-LT
User Rank
Platinum
Nice fix
Cadman-LT   5/20/2012 9:51:59 PM
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Very nice fix. So crazy that you solved the problem and reengineered their design so quicky. Applause! Isn't it lovely that it takes an engineer to own anything these days, well to make them work properly anyways!

Charles Murray
User Rank
Blogger
Re: Hot refrigerator
Charles Murray   5/1/2012 8:19:07 PM
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Just curious, MMorgan: How long did those fridges from the 1920s last? Longer than today's?

rathomas
User Rank
Iron
Re: Hot refrigerator
rathomas   5/1/2012 10:14:24 AM
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My GE side-by-side was subject to a class action suit which GE settled without admitting fault.  In the settlement, we got a couple of free service visits (started failing just outside the warranty period) and eventually a new freezer door to replace the dispensary mechanism that had been damaged by moisture.

All of that happened *before* the fan motor went out!  I replaced the fan assembly with one with ball bearings and designed for a 2 or 3U rackmount server application.  That fan has now been running at least as long as the original one.

So when it came time to buy a new fridge for the new house, we steered very clear of GE and wound up going with Whirlpool.  A couple of months after it was installed, we noticed that the compressor, fan and all had stopped working.  When pulling it away from the wall to investigate, it started up again.  Loose connection somewhere!  I dug into it (don't tell Whirlpool, it's still under warranty!) and found single wire termination was not pushed all the way into its keep in a Molex style connector.

So, design compromises and errors?  Yes.  Poor quality control?  That too.  Or maybe I'm just unlucky ;)

MMorgan
User Rank
Bronze
Re: Hot refrigerator
MMorgan   4/25/2012 8:00:49 AM
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It is inevitable that the more parts you have, the more parts there are with a Mean Time Between Failure that can at time be additive. I remember seeing very old refrigerators, (in the 1950's) that were made in the early 1920's. These had only a compressor and coils, no fans, no timers, not even a light inside. Of course they were more reliable.

Charles Murray
User Rank
Blogger
Re: Hot refrigerator
Charles Murray   4/24/2012 8:34:20 PM
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I agree with you that newer refrigerators have features that are more likely to be problematic, MMorgan. It's ironic, though, that progress gives our refrigerators shorter useful lives and less reliability. Seems like it should be the other way around.

bob from maine
User Rank
Platinum
Refrigerators and pet hair
bob from maine   4/23/2012 12:35:40 PM
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Annual vacuuming of the air passage and coils under and in back of the fridge reaps great benefits in reduced energy consumption and extended fan life. My dog and cat enjoy lying in front of the fridge (can't have someone going into the refer without finding something to share I guess) and apparently laying quietly causes their hair to fall-out in great quantities. The hair gets sucked into the grill and after a time will block 90% of the air movement. This will cause overheating and early failure of the fan motor. Newer refers have almost silent motors which seem to be more susceptable to overheating. Older model fans were much louder and drew significantly more current, plus were designed to have free-air movement up the back and out over the top so a dead fan may not even be noticed unless you closely monitored your electric bill.

MMorgan
User Rank
Bronze
Hot refrigerator
MMorgan   4/20/2012 8:01:17 AM
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I'm surprised at your problem.I have had only two refrigerators over 46 years in my home and found them to be very reliable. While not trouble free,they are unusually reliable. Replaced a defrost timer once on each of two. Had a Sears Kenmore for about 25 years, replaced a defrost heater after about 20 years and sold it because of redecorating.

Maybe the newer ones are having these problems. On the other hand, the newer ones with all of the bells and whistles are bound to be more problematic. More parts, more parts to wear or fail.

Looks to me like you did a pretty good job of trouble shooting....isn't that what we do as engineers. Bravo!

tekochip
User Rank
Platinum
Re: new vs old frig designs
tekochip   4/17/2012 9:47:38 PM
NO RATINGS
When I was doing appliances we would frequently lament the hours upon hours of engineering time we would pour into a motor control because the customer had bought the cheapest iron for the motor.

Charles Murray
User Rank
Blogger
Re: Lean, inexpensive, "smart" -vs. robust quality?
Charles Murray   4/17/2012 7:08:17 PM
Putting your story into context, it seems ironic that appliance makers are adding capacitive touch screens to their fridges and washers, but (in your case, Bill) they are failing to make a refrigerator that lasts more than five years. I'm sure that a reliable refrigerator is far more important to you than a touch screen.

Thinking_J
User Rank
Platinum
new vs old frig designs
Thinking_J   4/17/2012 4:50:35 PM
NO RATINGS
There are only two significant areas of improvement/change in Frig design over the last 40 years...

biggest-  insulation of the temperature chamber

next biggest-  efficiency of electric motor(s) used

The remaining changes... minor (impact on energy efficiency) , possible exception: reduction in door opening for ice/water.. since I don't use ice or cooled water, it has not been an issue for me.

Insulation improvements are a traded against wall thickness (over all size vs interior size).. shouldn't affect reliability of frig.

Electric motor(s) and their control systems .. "efficiency" is OFTEN traded against "reliability".

When I was a electrician (in my youth) .. would often come across electric motors from 1930-50s that would likely never die. Reason: overbuilt (is that possible?) with extreme amounts of iron and electrical insulation space resulting in bulky/in-efficient motors that ran cool due to the mass and would last as long as the bearings didn't fail...  - Society expected capital equipment to last forever and energy was cheap.

Now the engineers are asked to push the limits for efficiency with the latest materials.. in expectation of:

-lower energy consumption

-expected further improvements in materials (want to rotate "out" less efficient appliances in the field)..

- and yea, it makes business sense to have this planned obsolesce (speed of money and it's effect on economy).

Closer to the limits of materials.. the less reliable the product. .. AKA risk vs reward.

Is that a conspiracy? Gov. mandated social engineering?  Unstoppable technological change? Response to Energy costs? Response to environmental concerns? Capitalism at work? ....    There is some truth in all of these observations, just a matter of perspective.

Example:

If someone made a Refrigerator that was guaranteed for 30 years.

Would society be OK .. being stuck with no improvements in energy efficiency because of much lower rate of replacement? After all, a refrigerator's energy consumption is a pretty small percentage of a household's total. But it may have a significant total in a community. Tomorrow? someone MAY create a refrigerator that is another 25% more efficient... but no one will buy it, because they don't need a replacement  and it will take 20 years of energy saving to recoup the investment.

The specific choice is often determined by expectations based on the past (my old frig lasted 25 years!) . When the best choice may not be related to this past experience.

Change or "faster rate of change" .... creates tough decisions.

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