Here is a link for the schematic of my old (1985±) Jenn-air wall oven (single).

https://plus.google.com/photos/11010...CKTEiNy-2YCkMw

Please note that the BR wire that is cut off at the bottom of the scan, goes to the splice point to the right.

Said oven has been used many times in the "self-clean" mode to clean numerous metal car and motorcycle parts (my wife is wonderful), frequently all the disassembled parts to my popcorn machine. Said "self-clean" feature no longer works. Here is what is konwn:

Broiler heating element works. Bake heating element works. Oven works fine as an oven and all timer functions work. Thermostat absolutely no longer available, but, as mentioned, temperatures are maintained within a close range (check with remote sensing thermometer)while doing preheat, baking and broiling.

Upon trying the clean cycle, the manual door-lock is prevented from being opened, the oven reaches 580°F (suspiciously close to the 600°F limit switch and 600°F lock) and then suspiciously shuts off, thereby allowing the door to be manually opened.

Can somebody with a good eye trace out this diagram and tell me where I could take voltage or amperage readings to find the 'break' in the circuit. Of course the 975°F limit within the thermostat could be opening too early, and since no longer in production, that is what I would like to rule out.

Also, if somebody could explain the the symbols withing the thermostat. It appears that the 975° switch is normally closed? while the 600° switch is normally open. What pulls the 600° closed? Is that resistor symbol below, labeled SO, CO and OM, really a coil?

The oven is totally pulled out of the cabinet and all the parts and terminals are accessible. My immediate hope is to (upon advice from group) be able to place a jumper somewhere and get one more cleaning cycle out of this oven.

Thank you all,

Ivan Vegvary

replying to Ivan Vegvary , passerby wrote:
ivanvegvary wrote:

Also, if somebody could explain the the symbols withing the thermostat.
It
appears that the 975� switch is normally closed? while the 600� switch

is normally open. What pulls the 600� closed? Is that resistor
symbol
below, labeled SO, CO and OM, really a coil?

The whole schematic is a bit too complex to take in quickly but these
questions I think I can address. Those 975 degree LIMIT and 600 degree LOCK
are bimetal switches. You are right, the 975 normally closed, 600 normally
opened. When 600 LOCK closes, it activates (opens) the normally closed "Clean
Relay" and kills both the BAKE and BROIL elements.

The resistor below is a rheostat and those are not "O"s - those are just
symbols for screw terminals. So, it's "S" (south?) "C" (control, wiper) and
"N" (north?)

Looks like you may need to poke around the "Clean Relay" at the time it
activates to see which voltages are there and which aren't. Perhaps the relay
is stuck (commutates mighty high current) and the 600 degree LIMIT is what
actually kills it, not the 600 LOCK.

Good luck!

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On Wednesday, April 24, 2013 5:32:09 PM UTC-7, passerby wrote:
replying to Ivan Vegvary , passerby wrote:

ivanvegvary wrote:



Also, if somebody could explain the the symbols withing the thermostat.

It

appears that the 975� switch is normally closed? while the 600� switch



is normally open. What pulls the 600� closed? Is that resistor

symbol

below, labeled SO, CO and OM, really a coil?



The whole schematic is a bit too complex to take in quickly but these

questions I think I can address. Those 975 degree LIMIT and 600 degree LOCK

are bimetal switches. You are right, the 975 normally closed, 600 normally

opened. When 600 LOCK closes, it activates (opens) the normally closed "Clean

Relay" and kills both the BAKE and BROIL elements.



The resistor below is a rheostat and those are not "O"s - those are just

symbols for screw terminals. So, it's "S" (south?) "C" (control, wiper) and

"N" (north?)



Looks like you may need to poke around the "Clean Relay" at the time it

activates to see which voltages are there and which aren't. Perhaps the relay

is stuck (commutates mighty high current) and the 600 degree LIMIT is what

actually kills it, not the 600 LOCK.



Good luck!



--

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rec.crafts.metalworking and other engineering groups

Hey, thanks Passerby. This certainly gives me a trail to follow. But question about the rheostat. So this is probably a 'leave alone' adjust only when need to rheostat? Also, what in the world would close the 600 lock?
Thanks

replying to Ivan Vegvary , passerby wrote:
ivanvegvary wrote:

Hey, thanks Passerby. This certainly gives me a trail to follow. But
ques
tion about the rheostat. So this is probably a 'leave alone' adjust
only w
hen need to rheostat? Also, what in the world would close the 600
lock?
Thanks


Sorry, Ivan, not sure what you mean by "leave alone" - that rheostat
appears to be your temperature control setting for the oven. The symbols
in the thermostat area are a bit weird, I give you that. The little
triangle at the end of the switch usually denotes manual control (with a
handle or knob). But limit switches are usually bimetal (and in any case
can't have manual control). So the Limit 950 looks like a wrong symbol, it
has to be something like the other two limit switches below it, to the
left: FAN LIMIT 175 F and 600 LIMIT further down - those are definitely
bimetal and change state automatically as the temperature exceeds the
preset limit.

The 600 LOCK contact in the thermostat though must be the "Self Clean"
position of the temperature handle or whatever switch turns the "Self
Clean" feature on. So, the 600 LOCK must be manual (and the symbol
suggests that) but 600 LIMIT is bimetal, trips by temperature.


--


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