mikegi wrote:
This is the third thermal cut-off that's gone out in the past few months.
We're about ready to toss the dryer and buy a new one (and stay as far away
from Kenmore as possible). Here's our Kenmore saga:

Almost two years ago the heating element in our first Kenmore dryer went out
(it was 6 years old). The unit would spin, just no heat. The element was
replaced. About a month later the dryer wouldn't even start spinning. We
bought a new Kenmore dryer shortly thereafter thinking the first was a
lemon.

Fast forward one year to Oct2005. At 16 months old, the new dryer stopped
heating. It would spin but there was no heat. I tested the various heating
canister parts and discovered that the hi-temp cutoff device was
open-circuited (everything else was fine). Here's a thread on that incident:

http://groups.google.com/group/alt.h...718ba2ba9f3b87

Everything seemed to be fine until Jan2006 when the exact same thing
happened:
http://groups.google.com/group/alt.h...7a3c26a98d1c69

So I replaced the cutoff switch again and cleaned out the dryer vent with a
"toilet snake" device. There was quite a bit of lint build-up but nothing
extreme. I figured that this would solve the problem once and for all. Yeah,
right.

A few days ago, the dryer wouldn't heat again. Yep, same part went out. The
guys at the appliance parts store told me repeatedly that the vent is
blocked and causing the overheating. They said to run a leaf blower in it to
clear out any blockage. Well, I just did that and there was no big chunk of
lint that came out. I simply don't think lint build-up is the problem.

How do these damn dryers work? For example:

1) There are various temperature settings on the unit (Cotton-high heat,
etc.). Does the dryer controller use the main thermostat to sense the
temperature and turn on the coil when it needs more heat? What happens if
this main thermostat underestimates the temperature, will it overheat the
unit and blow the cutoff switch?

2) Could the heating element stay on too long after the dryer shuts off? I
could see this blowing the cutoff switch due to lack of circulation.

3) Regardless of the exact cause, why isn't the resettable temperature
cutoff triggering **first** and preventing the non-resettable one from
blowing. Makes no sense to me. I believe the guys at the parts store said
there's a 100deg temperature difference between their triggers.

4) Could the heating element be too close to the cutout switch?

For reference, there are three devices attached to the heating element can:
the main thermostat, the resettable cutoff switch, and the nonresettable
cutoff switch. They're aligned from front to back in that order.

Any help would be appreciated.
Mike




Non-resettable? Are you talking about a thermal fuse? If so, then yes,
look at the temperature sensor, or the heating element. More likely the
sensor.

--
Thank you,



"Then said I, Wisdom [is] better than strength: nevertheless the poor
man's wisdom [is] despised, and his words are not heard." Ecclesiastes 9:16