Customer Support 7 days a week

Welcome Guest! You can not login or register.

Notification

Icon
Error

Options
Go to last post Go to first unread
cjwoodlee  
#1 Posted : Tuesday, August 20, 2013 7:03:17 AM(UTC)
cjwoodlee

Rank: Member

Groups: Registered
Joined: 8/20/2013(UTC)
Posts: 5

This is the Kenmore Dryer:

110-66912692
I have a heating problem. The heat will not shut off and subsequently blows the fuse.
Cycling thermostat and high limit thermostat are OK / new.
HEATER coil test good at 10 ohms. *It is not shorting to the housing frame anywhere. Confirmed / reconfirmed several times. Also, upon visual inspection coil looks good. (Entire harness is clean no nicks, cuts, burns etc.) The heater only comes on when the dryer is started. NOT when the timer is turned to an "on" setting before starting the dryer. It can be heard running "ticking" when moved to on. The heating element will shut off after turning off the dryer but only after it is manually stopped.

The timer had a loose / broken contact point tip between the white & tan terminals inside. *I have ordered a new FSP timer. Obviously the timer is an issue but I am unsure if this powering of the heating element / coil issue will be solved, yet, by replacing just the timer.
The Drive Motor switch appears to be ok. Motor was removed. Contact cover removed. Contacts are not welded shut. Continuity between options tests good for contact & release.
Entire unit is extremely clean and well cared for at 14 (fourteen) years old. (No obstructions in venting.)
Sponsor
See inside of your appliance - diagrams and part photos for virtually every model.

powered by AppliancePartsPros.com
 
denman  
#2 Posted : Wednesday, August 21, 2013 4:47:12 AM(UTC)
denman

Rank: Advanced Member

Groups: Senior Expert
Joined: 2/29/2008(UTC)
Posts: 19,638

Thanks: 1 times
Was thanked: 11 time(s) in 11 post(s)
See the attachment for the wiring diagram..

[COLOR="Blue"]The heat will not shut off and subsequently blows the fuse.[/COLOR]
Just to be sure, is this the thermal fuse on the blower?
Often people also call the thermal cut-off on the heater a fuse.

[COLOR="Blue"]The heating element will shut off after turning off the dryer but only after it is manually stopped.[/COLOR]
I am assuming that this can be done by opening the door or turning the timer to off.
Does the heater stay off in air only?
Does low heat setting actually change the heat output?

[COLOR="Blue"]
Obviously the timer is an issue but I am unsure if this powering of the heating element / coil issue will be solved, yet, by replacing just the timer.[/COLOR]
I also doubt this is your problem as the timer cannot keep the heater on as even if Timer Switch 2 was shorted (contacts welded together) the cycling thermostat should regulate the heat.

You seem to have done a very thorough job of troubleshooting so I am also pretty well stumped.
Although the odds are very high I would check the new operating thermostat.
Hold it onto a stove element or heat it's face with a soldering gun to be sure that it will open.
If your oven temperature regulation is good then you could even put it in there to see if it does open at around 150 degrees F.
File Attachment(s):
66912692.pdf (199kb) downloaded 5 time(s).
THIS FORUM IS DEAD!!!!!!!
cjwoodlee  
#3 Posted : Wednesday, August 21, 2013 6:02:11 AM(UTC)
cjwoodlee

Rank: Member

Groups: Registered
Joined: 8/20/2013(UTC)
Posts: 5

Originally Posted by: denman Go to Quoted Post
See the attachment for the wiring diagram..
*Thanks for the schematic.

The heat will not shut off and subsequently blows the fuse.
Just to be sure, is this the thermal fuse on the blower?
Often people also call the thermal cut-off on the heater a fuse.
*This is the thermal cut-off on the heater.

The heating element will shut off after turning off the dryer but only after it is manually stopped.
I am assuming that this can be done by opening the door or turning the timer to off. *Yes, opening the door or turning off at the timer.
Does the heater stay off in air only? *Stays OFF on Air Dry
Does low heat setting actually change the heat output? *Low heat setting DOES NOT change the symptoms - heater stays on constant.


Obviously the timer is an issue but I am unsure if this powering of the heating element / coil issue will be solved, yet, by replacing just the timer.
I also doubt this is your problem as the timer cannot keep the heater on as even if Timer Switch 2 was shorted (contacts welded together) the cycling thermostat should regulate the heat.

You seem to have done a very thorough job of troubleshooting so I am also pretty well stumped.
Although the odds are very high I would check the new operating thermostat.
Hold it onto a stove element or heat it's face with a soldering gun to be sure that it will open.
If your oven temperature regulation is good then you could even put it in there to see if it does open at around 150 degrees F.


*I have performed the griddle test on both the cycling thermostat and the limiter on the heater. Both are new FSP. **I have suspected the temp setting selector switch. The continuity tone on the meter on the low setting goes haywire before fizzling out. Symptoms do remain unchanged with the temp selector unplugged, as heater still stays on. (The blue resistors on the plug show continuity although I did not compare against thier color coding values) I guess this works by the selector fooling the cycling thermo with a heater.
*Also, the unit sometimes will not start on air dry until the timer was moved a ltttle. It would then start without the start switch relay. However, I suspect the new timer will clear this up. But it has also had me wandering if the start switch / relay is also suspect.
denman  
#4 Posted : Wednesday, August 21, 2013 8:01:49 AM(UTC)
denman

Rank: Advanced Member

Groups: Senior Expert
Joined: 2/29/2008(UTC)
Posts: 19,638

Thanks: 1 times
Was thanked: 11 time(s) in 11 post(s)
The thermal cut-off is a different kettle of fish.

Check all seals in the unit including drum and blower.
The reason is that the from the heater up to the blower the system is actually under a vacuum. If it sucks in room air then the cycling thermostat sees this and keeps the heater on.

Check the lint filter. Sometimes fabric softener residue can coat it reducing the air flow through the system. It should be cleaned with soap and water if coated.

[COLOR="Blue"]I have suspected the temp setting selector switch. The continuity tone on the meter on the low setting goes haywire before fizzling out. Symptoms do remain unchanged with the temp selector unplugged, as heater still stays on.[/COLOR]
I do not think it is in this area. In normal/high heat they are disconnected.
I am not sure about the fizzling out.

[COLOR="Blue"]I guess this works by the selector fooling the cycling thermo with a heater.[/COLOR]
Yes it adds heat to the thermostat so it thinks the unit is hotter than it actually is.

I seems strange that it keeps popping the thermal cut-off.
The hi-limit should prevent this. It should open at 225 while the thermal cut-off is at 350 degrees F.
One thing to note is that the hi-limit is just a safety with the thermal cut-off as an extra safety. So if it does start opening/closing it will not last very long.
Unlike the operating thermostat whose contacts are made to do this all the time.
THIS FORUM IS DEAD!!!!!!!
cjwoodlee  
#5 Posted : Wednesday, August 21, 2013 2:59:41 PM(UTC)
cjwoodlee

Rank: Member

Groups: Registered
Joined: 8/20/2013(UTC)
Posts: 5

Ok This makes sense, after the timer arrives I will ensure the cycling thermo is working at spec, again. Then I will check the integrity of the heater box. I did order a new seal for the blower to housing ring. Also, there is that seal from the lint screen box to the blower box and the drum felts, of course. There is also that tube vent (probably for lint overstuffing bypass). What I am going to do then is use a butane torch to heat up the cycling thermo. If it cycles then obviously there are sealing integrity issues. Hopefully, it would be nice to see the timer get this done. Give me until Saturday since I can't pick this back up until Friday.
cjwoodlee  
#6 Posted : Wednesday, August 21, 2013 3:13:04 PM(UTC)
cjwoodlee

Rank: Member

Groups: Registered
Joined: 8/20/2013(UTC)
Posts: 5

I don't know if there is such a thing as a partially burn't out coil and it would not be getting hot enough, as well. i am at 10 ohms - enough to go over 360 - Make sense on the integrity seals
denman  
#7 Posted : Wednesday, August 21, 2013 4:02:23 PM(UTC)
denman

Rank: Advanced Member

Groups: Senior Expert
Joined: 2/29/2008(UTC)
Posts: 19,638

Thanks: 1 times
Was thanked: 11 time(s) in 11 post(s)
Your coil resistance is within the specification.
Also you have checked it to be sure it is not grounded.

I am not totally ruling it out but it would have to be something weird going on with it.
THIS FORUM IS DEAD!!!!!!!
cjwoodlee  
#8 Posted : Saturday, August 24, 2013 2:40:29 PM(UTC)
cjwoodlee

Rank: Member

Groups: Registered
Joined: 8/20/2013(UTC)
Posts: 5

Thanks for the help.
When I arrived home this Sat afternoon, the new FSP timer had arrived.
***This solved the problem!

***We thank our God and Father of Jesus Christ and yourself for providing the way and help, of course.

After studying the schematic this week some I was becoming more confident (yes hoping) that the way the contact was broken T ~ W OR neutral was bypassing the cycling thermostat through the motor switches?
SEE SCHEMATIC timer switch 4.
So, I believe, since this would not stop making contact when it should on all cycles the white neutral actually became a direct "constant red"?

It is like a new unit. Every inch of this thing is clean. We have a new cycling thermostat on the blower box, thermal cut off "fuse" & high limit thermo on the heater. All FSP made in the USA. When it cycles is sounds nice and tight. Plus you can not hear the new timer running.

With the unit venting into the laundry room, no clothes in the dryer with the lint screen in place, cycling times are: 1) On the lowest setting - 70 (seventy) seconds 2) On the highest setting (or "roast 'em good") - 95 (ninety-five) seconds.

Next project: If you would like I will provide you with my research on the vent to out side booster vent fan options from FANTECH that I plan to install, next. This should ensure it keeps it well vented and reduces drying times, as well!

Thank You, Chris Huntsville, AL
Users browsing this topic
Forum Jump  
You can post new topics in this forum.
You can reply to topics in this forum.
You can delete your posts in this forum.
You can edit your posts in this forum.
You cannot create polls in this forum.
You can vote in polls in this forum.