GE V12 (Model 78D51121911) Dryer- Auto dry will not work

[paid2fish]

Hello, I have a GE V12 (Model 78D51 1219 11) that dries fine on the timed dry setting but does not advance the timer on the auto setting. I read on another page that this indicates that it probably is not the timer but the page does not elaborate. Any suggestions of what to look at and how to test it?
Thanks,
Ed

 

[rickgburton]

GE Dryer-auto dry will not work.

I tried to look up your dryer but I don't think thats a good model #. They usualy start with three letters the first one a D. If you have two heating elements that are strung around the back wall behind the drum, it sounds like one of them is out(Broken).This will keep the auto cycle from working.

 

[paid2fish]

Rick,
I have double checked the Model number and that is what I get, the dryer was manufactured in canada, soes that make a difference in the model number? I have checked the heating coils (2) strung around the back of the drum with a multi-meter and they are intact. I wanted to check the humidity sensor but I am not sure how to procede or which is the correct sensor. I want to beleive the sensor in the door is the humidity and the one near the heating coils is temperature? Is the sensor circut usually open or closed whrn not in use? Any other ideas?
Thanks,
Ed

 

[rickgburton]

Thermostats..

Behind the front panel and mounted by the lint filter are your cycling thermostats.The one mounted on top of the elements is the safty thermostat.All are normally closed.

 

[paid2fish]

not sure where to go from here...

I have checked the operating thermostat and it opens at 140-150 degrees (part ID says 140), and the temperature inside the dryer ranges from 120-170 degrees. The timer motor gets power when on the timer setting but gets none on the Auto setting. Is there anythig else I should be checking? Any suggestions would be very appreciated.
Thanks, Ed

 

[rickgburton]

Timer Motor...

In the automatic cycle,the timer motor only shows 110vac when the cycling thermostat opens. When the the thermostat is closed,the timer does not advance.

 

[paid2fish]

I checked the power to the timer while the dryer was running on auto for several heat/cool cycles and got zero volts with thermostat open and closed. There is a resistor attached to the cycle selection housing with a wire attached to the timer and the other attached to the selection buttons. Could this be the problem? I get zero resistance on the meter...
Thanks,
Ed

 

[rickgburton]

Model number ?...

Some of the older dryers have a 5watt resistor that does effect the auto cycle. Unfortunatly I haven't been able to look up your dryer with the model number:78D51121911. Where is the model # plate located on your dryer?

 

[paid2fish]

model number

This is an older machine and the model number is located on the front panel, behind the door.

 

[Lukeehann]

model number

This is an older machine and the model number is located on the front panel, behind the door.

Hi Ed,
Did you ever get your timed dying to work on your old GE V-12 Model 78D51 1219 11 dryer?
I just gave mine a good cleaning, changed the belt and replaced the heating elements.
My automatic setting just runs hot continuously, without shutting off (I don't use it and put tape over it to warn others). It still does not work after a good cleaning.
I looked everywhere for the humistat and couldn't find any other devices except for the two thermostats (one in with the elements and one just inside the door) I can post the schematic here if anyone else can help us.

 

[Dan O.]

Unfortunatly I haven't been able to look up your dryer with the model number:78D51121911

It is an ancient (1970's?) Canadian GE dryer. I have no idea how it ended up in Raleigh, NC for the OP.

My automatic setting just runs hot continuously, without shutting off (I don't use it and put tape over it to warn others). It still does not work after a good cleaning.

On many older machines the timer will only advance on an 'auto' or 'permanent press' setting when the heater cycles off. If the heat isn't cycling on and off on that setting, someone needs to look into why.


Does the heat cycle on and off when set on a regular cycle or overheat there too?

I looked everywhere for the humistat

They don't usually use any kind of humidistat for such a setting on dryers. There are several different methods used for that setting, the one linked below has been used on all makes of dryers once upon a time and is the oldest method.

LINK > The Appliance Clinic : Electric Dryer : Automatic Cycles

couldn't find any other devices except for the two thermostats (one in with the elements and one just inside the door)

The one on the heater housing will be the safety thermostat. The other is the cycling thermostat. The cycling thermostat will be the one likely needing scrutiny.


Please post a clearer photo of the indicated parts of the wiring diagram including the Timer and Fluor Lamp area of the diagram, toward the top.



Dan O.