The clothes in our Kenmore dryer became so hot during a load one day that we thought they were going to catch fire. I ran the dryer and watched the heater box. The heater element was glowing red hot and did not respond to box temperature or heat setting. Naturally, my first thought was that either the temperature sensor had blown or the high temperature cutoff switch was bad.
I pulled the dryer out from the wall and took the back off to access the controls. While running the dryer, I was able to determine that the switches were operating correctly, but the heater element was still glowing red. Next, I pulled the cover off of the heater element compartment and ran the dryer again. To my amazement, half of the heater element was turning on and off properly, but the other half was full on all the time.
The heater was coiled nichrome wire that was mounted on insulating porcelain standoffs. There were six lengths of the heater wire, about 18 inches long with an insulator at the ends only where the heater turned. After many years of use, and many heat cycles, the middle loop had fatigued and was curved toward the firewall between the heater compartment and the clothes compartment. Of course, this baffle was metal, connected to the rest of the dryer frame, and therefore, grounded.
The thermostat and over-temperature switches were both on the same, single side of the 220V line. Consequently, when the center of the element contacted the ground there was approximately 110V across that portion of the element all the time. Hence, there was always lots of heat being produced whenever the dryer was on, with no control. Fortunately, there was no power applied when the dryer was off, otherwise we would have been paying an excessive electric bill until it was repaired. We also would have been in danger of a fire.
Kenmore should have designed the heater layout with more support at closer intervals than 18 inches, especially since this was in an appliance that was constantly subjected to vibration and the thermal cycles that would tend to flex the nichrome wire.
This entry was submitted by Thomas R. Clem Sr. and edited by Rob Spiegel.
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In general the Kenmore appliances at very good. We have a washer and dryer (gas) that have lasted a long time and work fine. The issue that you ran into, and your suggestion, make sense. You would think that a company that had been putting out these products for so long would have the engineering knowledge to avoid such problems. This is especially true since it could have been a safety issue.
Good points, Naperlou. One of the questions would be -- how recent is this particular model? Time after time with the Made by Monkeys blog, the problems are with the newer models and their control panels.
Like naperlou, I've also had good experiences with Kenmore machines and I think their good reputation is well-deserved. Of course, I bought all of mine over 10 years ago, so I'm not sure how well that reputation has lasted. This Made by Monkeys makes me think that perhaps we need a new acronym: DFF (Design-For-Failure), along with all the other DFx designations. This heater layout obviously wasn't DFF-ed.
Newer models and control panels...what does that say about this generation of engineering? You would think it would be rock solid and not subject to these issues because of the wealth of experience behind them. Control panels aren't rocket science - I find this A.puzzling and B.concerned about leaving the house if a household appliance is running...
I never leave the house when an electrical or gas appliance is running. The only exception is the wood stove, which is a lot more reliable, plus there's no off switch anyway (part of the design).
Good point, Nancy. In these Made by Monkey blogs, we regularly hear about how the families had washers and dryers for 20 or 30 years with no problem. Then they purchased a new one . . . Seems that the mechanical aspects of the appliances work just fine. But watch out for the electronics.
I see what you are saying Ann and it is no doubt excellent practice - but refrigerators run all of the time...and while I don't typically leave the house if appliances are running - I can't say that about the dishwasher which becomes invisible to me after the main wash cycle has completed...until a plastic spoon fell through the top basket and was lodged against the heating element when the heated dry cycle came on - between the burning smell and the smoke coming out of it - that could have ended quite badly. It really is hard to predict all of the scenarios that can happen in a household - especially with two teenagers! LOL I agree - only running appliances while you are home is safest...
And with all of the fancy electronic features that are being added all of the time, Rob - it will probably get worse. We just bought a washer a few months ago and we no longer set the water level - the washer senses it. I hate to think what will happen if the water level sensor circuitry goes out...
You're right Nancy, I should have included the fridge in my exception list. My main concern used to be the clothes dryer until I heard about all kinds of problems like the one you describe in your dishwasher. So I have a zero-tolerance policy with electric and gas appliances, with the exception of the fridge.
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