Kenmore dryer 110.68972890 won't start/tumble

[susan_oldwork]

We have an older Kenmore electric dryer, model 110.68972890  .   About four years ago it would tumble but not heat, and this forum talked me through the process of figuring out which relay had failed, ordering a replacement which turned out to be a newer part, and making the needed changes to get the new part to work in my older dryer.   (I can't access that thread anymore, but it was from April of 2014).

Today the dryer developed a new problem.  I was running a load with the timer set to shut off at damp-dry, which it seemed to do, but when I then tried to restart the dryer to complete the rest of the load,  it won't start to tumble.      The light is on so there is power, and pushing the "start" button produces a click but no tumbling.  Pushing the button again won't produce any noise unless you open and close the door first - or just open the door and manually close the interlock tab, which also turns out the light.     The timer behaves as it normally does when you close the door and don't start the dryer - it gradually advances to the "off" position.

So I think I can rule out several things:  It's got power, the safety interlock is still operating, the timer circuits are still operating.    

Is there any way to tell if this is as simple as the on/off switch?    What else might be causing this issue?

 

 

[bowhunter]

It sounds like your thermal fuse is faulty. It’s usually mounted on the blower assembly next to the cycling thermostat. After unplugging your unit you will need to check this small white fuse which is about and inch and a quarter long and about a quarter inch wide. It has 2 wires running to it and you just have to remove 1 wire and chech with an ohm meter to see if it has continuity. 

[Mattwilly91]

This model also has a belt switch on it according to the parts breakdown I was looking at. It could be your belt is broken and not having that switch depressed. I would check that as well. You'll see if that belt is broken or not when you open that lid. 

 

[bowhunter]

You are right

[susan_oldwork]

So far I've just opened the flip-back top panel where the controls are, and the kickplate to try and find the thermal fuse.    Is there a diagram telling me where the thermal fuse would be?

THanks for the thoughts on the belt.    I haven't exposed the whole belt yet, so it might have damage like a crack or kink that I'm not seeing, but one of the earlier things I did was to turn the drum by hand to see if there was still tension on the drum - it felt normal.    But I will pop the lid and front panel off and double check.      If at all possible I'd like to avoid removing the drum -  it's been, oh, 30 years since I did a belt replacement, and even then I had to cheat and build some cribbing to help me get the drum in and out, as I'm short.   I'm shorter and less strong now :-).   

[bowhunter]

If you have the kick plate off then if you can pull the dryer away enough to lean it back get on your knees. Utilizing a flashlight you will see the thermal fuse on the blower housing. It will be facing to your right on that housing.  It is held in place by 1 screw ( 1/4 inch hex head). There are 2 wires running to it. Remove the 2 wires. It doesn’t matter how you put the wires back on. Just remove the screw with a very short 1/4” nut driver as there is just enough room between the blower housing and drum to get a short tool in there. Push the fuse slightly away and up and it will come right out. (It’s notched) Check it with an ohm meter for continuity. If it’s faulty replace it. Refer back to first comment for the visual description of the part.

 

[susan_oldwork]

Thank you for the help so far.   I've confirmed that there is no continuity in the left-hand thermal fuse.   (I had to remove the outer layer of the blower housing before I could find the fuse mounted in the inner housing and  get the fuse out).      Is the oval object  on the right another thermal fuse and should I remove and check it as well?  The "Repair Clinic" site linked from appiantology does list two fuses for this dryer.

Before I replace the fuse(s), I'd like to inspect the ducting *internal to the dryer* for lint.   Is there a way to remove the inner blower housing - the part that has the blower wheel - so I can see inside the straight-run of vent pipe that is inside the dryer?    I would like to be sure that when the vent has been cleaned from the outside, it has been done correctly, and I can't move the dryer on my own to access it from the rear.   The blower fan turns properly and wasn't clogged with lint, but there was a little visible on it, and I'd like to check to be sure the unit is safe before attempting to put it back into service.

I could guess that it's possible that there isn't a lint problem - the dryer is rather old, and everything in the house was subjected to unusual thermal stress when we had to keep the house as hot as possible for two weeks to help remediate wet ceilings and walls from a roof leak - but I would much rather be safe and check that this has been cleaned properly.

Removing the left-hand thermal fuse gave me a hole about 3/4" wide by 1.5" across.   If I can't get the blower housing off,  could I remove that second fuse/whatever and then just stick my 1/2" wide flexible vacuum hose into the holes to see if it picks up any lint?

 

 

[bowhunter]

It would take a while to explain. The venting to the blower is in the back but you first must remove a hex screw 5/16”  first, located by taking the 2 Phillips head screws out of the lint catcher on the top right corner of your dryer if that’s the style you have and then pop the top by inserting a screwdriver in between the top and the cabinet of the dryer in the front. It has a flimsy hinge so you can lean it back out of the way as long as you lean it against something. If you are in front of your dryer looking towards the back of your dryer you will find the 5/16” hex screw about 1:00 behind the drum. That holds the top of the lint filter assembly on. The lower the top of the dryer and turn it around and remove all the 1/4” hex screws holding the back on. The lint housing attaches to the blower assembly with 3 or 4 1/4” hex screws. After removing the screws the assembly is ready to remove which you do by push it up and then pulling out and down kind of all in one motion. I don’t know if this is the model of your dryer but if you have a lint filter that you you clean by removing it from the top of the dryer then these instructions will be correct.

[bowhunter]

I believe you can find a video on this on here or you tube

[susan_oldwork]

This is the dryer with the lint filter at the bottom of the door.          I did look for videos on removing the internal housing, but all I found was instructions on how to replace the blower fan blade assembly - which can be done without removing the internal housing.

It sounds like I might be better off just working through the mounting hole for the thermal fuse in the housing.    What's the unit to the immediate right of the location that I pulled the thermal fuse out of?  Should I pull it out and test it too?  It has two terminals, one with a red wire, one with a white wire with a red stripe.  It's close to the size of the thermal fuse, maybe 1/4" bigger, and roughly the same shape.    

I don't want to just blindly stick a cleaning hose down into that housing if there are probes or sensors that I could damage by doing that!  So I'd appreciate any info you can give me.

 

 

 

[bowhunter]

In order to access the blower you must remove the front of the dryer. I would look here for a video or you tube. It really isn’t that difficult. My instructions are for an older model and by the time I typed out the instructions on how to do your dryer I would develope carpal finger?

[susan_oldwork]

Let's spare your fingers!   I won't try to remove the internal blower housing.     (The external came off easily).

 

But do you know what that second unit is, next to the thermal fuse?  You were spot-on about how to remove the fuse (1/4" stubby), and it tests bad (no continuity).     I just don't know if I can/should do anything with that second one.       

 

 

 

[bowhunter]

The other is a cycling thermostat or thermistor. If the dryer got to hot which has nothing to do with the temperature in your house by the way and that caused the thermal fuse to blow, you would want to put a digital thermometer in the exhaust (after you replace thermal fuse)and make sure the heat was cycling up to 155+ a few degrees and down to 120+. If that’s  the case then it may have just been the thermal fuse was weak or your ducting to the outside of your house is plugged with lint. I do not recommend sticking anything in the opening where you removed the fuse.

[susan_oldwork]

Thank you for the explanation.   We were running the house as close to 100 degrees as we could per the remediation folks, and have in-floor radiant heat under the dryer, so the dryer was trapping heat - it was *very* hot over there.  Glad to hear that this would not have damaged the unit.   I've checked everything I can so far for lint inside and outside.  I will not put anything in the fuse opening.  

[bowhunter]

With radiant heat under the dryer, is this a recent thing? That’s not helpful as the dryer has to cycle and having a constant source of heat under it makes it difficult. I can’t say for sure if this could be a precipitating factor.

[susan_oldwork]

There's been radiant heat under the dryer for 50 years.  It's hot water based, in iron pipes in the slab floor.  It's normally not turned up that high, floor temps usually don't exceed 80-ish degrees, and air temps of course are lower.  It was just this one short term need to get the *air* temps up to 100 in most of the house that made it so dang hot over there.   

[susan_oldwork]

(Well, under 3 dryers in 50 years.  Not one dryer the whole time!)

 

[bowhunter]

Check your vent temp without the duct on to see what your cycling temps are. How far does your duct work travel before it hits the outside?

[bowhunter]

This is after you replace the thermal fuse of course.

[susan_oldwork]

The dryer is on an outside wall: it's connected by a rigid steel vent (not a hose) to an outside louvered vent.    From the back of the dryer to the outside air is under a foot.  I clean this regularly from the outside with a duct cleaning brush.    I am not physically capable of moving the dryer to disconnect the vent setup, but I do have a long-handled thermometer that I can pop in the outside vent so I will be pretty darn close to the back of the dryer for measuring temperature.  

 

[bowhunter]

Excellent. Good luck to you

[susan_oldwork]

Thanks for all of your help.

 

Just an update:  dryer is working now w/new thermal fuse.   When I first tried to do the temperature test at the vent, the flow was so strong that it pushed my thermometer out unless I held onto it firmly - so I don't think I have lint blockage.    (large headed compost thermometer).    I did want to do the temp test, though, and thought you might find what I used useful - I took a cooking thermometer that has a probe and a long cable that plugs into a fancy base unit and used it.    That let me insert the probe well into the vent, once temp was up around 130 I reset the min/max readings and went away, came back 10 minutes later and saw min of 115, max of 155.            Hopefully I'm all set for a while!

[bowhunter]

Good for you.?