Hi, we have an old (30 years?) Kenmore Heavy Duty Plus dryer that we've been repairing several times in the last year with the help of your site and I'm wondering if I'm missing something.

The belt broke, we replaced it. Dryer worked fine for a few months.

The dryer stopped working again, we noticed the red wire to the high limit thermostat on the heater was burnt through at the connector, read online elsewhere that this was not uncommon in an old dryer, cut the wire back and replaced the spade connector, dryer worked fine for a few months.

Dryer stopped working, bought digital multimeter, confirmed thermal fuse on blower is bad (no continuity, and dryer works when thermal fuse wires jumped to each other). Don't want to replace thermal fuse and just have it blow again so checked air flow and vent, all fine. Checked lint screen, blower wheel, etc, all fine. No noticeable leaks in drum, all seems to operate smoothly. Disconnected wires to heater element and tested heater, shows correct resistance internally and no continuity to frame to indicate a sagging element (that I could find, tried several spots on frame but admit this is my first time using multimeter). Ran dryer with thermal fuse wires jumped to each other and measured heat coming out of blower exhaust with thermometer, got up to about 130 and then cycled down and then back up. Cycling thermostat on blower shows continuity when cold. Haven't tested continuity when hot using electric griddle. Using an old meat thermometer to measure temp of air from blower, so don't know if 130 is really accurate or not, (seemed a little low to me?). Can't find temp rating written on cycling thermostat

Noticed female spade connector on red wire to cycling thermostat was partly broken and brittle and insulation at end of red wire somewhat melted and the male connector on the cycling thermostat is all blackened and dark compared to the other side.

So could this just be another old red wire/bad connection at the cycling thermostat that caused an intermittent malfunction that caused the dryer to get too hot and blow the thermal fuse, and if I fix the red wire connection at the cycling thermostat all will be well?

Or am I missing something that is in fact a root cause of these issues and the red wires burning at their connectors? Since the high limit thermostat and the cycling thermostat are both $30+ I'd prefer not to just replace them both if not needed. But more importantly don't want the dryer to cause a fire.

Mahalo and Aloha for your thoughts, from Big Island of Hawaii, 4 miles from the active volcano.

Hi Denman, thanks for the detailed reply. My previous repair to the red wire on the high limit thermostat looks fine BTW.

Embarrassed to say that upon crawling under the house (open post and pier construction) to examine the dryer hose exit I found that the very end of the dryer hose was somewhat constricted with lint. Not completely blocked but substantially narrowed. (the section of hose inside the house looked spotless)

So, I figured, maybe the hose constriction IS what triggered the thermal fuse to blow. So I changed out the dryer hose, sanded the connections on the cycling thermostat and repaired the red wire connector to the cycling thermostat. Connected the thermal fuse wires together and tested the dryer on a supervised and carefully watched load of laundry. Although it took a long time to get hot it did eventually reach 150 and cycle back down.

I was using the auto dryness setting and noticed the dryer wasn't shutting off on its own although the clothes seemed dry. So I thought, OK, maybe the auto dry setting is kaput and THAT's why the dryer overheated and blew the thermal fuse. So I switched to using the timed dry and that was working well.

Until on a subsequent load, it didn't... being careful not to leave the dryer unattended and having left my thermometer inserted in the dryer hose to spot check temps, I was somewhat surprised to see it registering 160 and the clothes were scorching hot. I shut it down and watched the next load carefully and saw it again go up approaching 170 at which point I shut it down and switched it to air dry.

So now I am thinking yes the cycling thermostat must be sticking intermittantly and I plan to order a new cycling thermostat when I get my new thermal fuse.

If you have any further comments I welcome your further input. Aloha !