Not Your Normal 'Door Locked' Question

Not your normal 'door locked' question

Crazy Stove -- Friday, 17 January 2003, at 12:38 p.m.

Model: Kenmore Free-Standing (?) gas rnage running off of Liquid Propane with electrically ignited burners and oven. Model Number: 790.75728991.
In my search for the answer to this question, I have seen a lot of posts from people with locked oven doors, but I believe I am experiencing a different problem. I think most of those people have inadvertenly entered self-clean mode without realizing it. In my case, I think there is an electronic fault or bad sensor causing the door to lock. I used to think that it was my wife 'hitting the wrong button' but I have since seen it happen a couple of times. One time was when the oven door was slammed shut (leading me to think of an intermittent short of some kind, the physical shock caused the connection to be momentarily made or broken), and two other times we were both sitting at the table, nobody was touching the stove at all. So it is impossible that she entered self-clean mode.

My wife also says that the stove acts 'brain dead' during these periods of posessed locking and unlocking.

Also, this problem does not cause the lock to stay on for a long time, only about a minute or so, and then it unlocks again.

I do not have the owners manual, so I can't tell if it is actually trying to self-clean, or if it is just having a problem that causes the lock to engage.

Here are my questions:

1) Where can I get user's (prefer an 800# or website/email to get a free replacement from the manufacturer) manual AND/OR a Service manual (I know these can be expensive, I would be grateful for someone to photocopy a few relevant pages for me or look over the diagnostic flowchart and help me pinpoint the problem. I'd of course pay for the pages. (You can email me at cybiko@netlimit.com). I should mention that I am an electrical engineer so I don't have any reservations about getting into the control circuitry...
2)Barring me actually getting a user's manual, if someone could briefly explain the operation of the self-cleaning function, I would appreciate it. Then I could try it out and it might help me figure out if the problem was in a self-cleaning 'mode' or just the door lock.
3) It's unrelated, but I am wondering if it is possible to light the stove by match when the power is out. I have heard the advice from a lot of people that you can start the oven and leave the door open if you need emergency heat. I don't see a way to get the gas flowing in the oven, since the controls are electronic. I can start the rangetop burners with a match, but I don't think this puts out enough heat. There is a 'warmer drawer' that has a (real) knob, but I don't know how to use it or start it (even with the power on).
4) Probably only someone intimately involved with fixing this model would be able to answer this, but what are the various activation modes for the door lock? Is it only activated by a signal from the microprocessor when it is in 'self-clean' mode? Or is it interlocked to a temperature sensor somewhere? Does it automatically go through and open-close-open cycle at powerup for testing purposes? An answer to this could give me more clues as to why this is happening.

Here's a general question: Why would manufacturers add in the extra hardware to lock a door during self clean? Just how hot does it get in there? People already know the inside of a stove is hot and to use caution, why lock them out and frustrate them more?

Thanks for your time reading this. I'll post any results I find. Wish me luck!

Re: Not your normal 'door locked' question *LINK* *PIC*

Dan O. -- Friday, 17 January 2003, at 3:25 p.m.

: Kenmore gas range Model Number: 790.7572899

That model was built for Sears by Frigidaire.

: I think there is an electronic fault or bad
: sensor causing the door to lock.

Several models of Frigidaire built ranges has a problem in the door activated light switch (see the link at the bottom of the page) which would cause the lock to function at odd times. In such a case, replacing the switch was the solution to the problem.

: Here are my questions

: 1) Where can I get user's manual AND/OR a
: Service manual

The only place you'll be able to get an owner's manual for a "Kenmore" product is from Sears. I don't know if they would have a service manual for your model or not.

: 2)Barring me actually getting a user's manual,
: if someone could briefly explain the
: operation of the self-cleaning function, I
: would appreciate it. Then I could try it out
: and it might help me figure out if the
: problem was in a self-cleaning 'mode' or
: just the door lock.

I don't know what happens on your specific model. Generally when set to self clean, the door locks and the control regulates the oven temperature for the set amount of time.

: 3) It's unrelated, but I am wondering if it is
: possible to light the stove by match when
: the power is out.

Most electronic ignition gas ovens can not be used if the power goes out. Some models that use a spark ignition system for the oven burner can.

: I don't see a way to get the
: gas flowing in the oven, since the controls
: are electronic.

On a model where the oven is solely controlled by an electronic control, the oven will not operate without power.

: 4) Probably only someone intimately involved
: with fixing this model would be able to
: answer this, but what are the various
: activation modes for the door lock? Is it
: only activated by a signal from the
: microprocessor when it is in 'self-clean'
: mode? Or is it interlocked to a temperature
: sensor somewhere?

It depends on how your range was designed. Some models lock by the rise in temperature, others by use of solenoid coils or an electric motor. See the following link for a description of each system.

LINK > After self cleaning the range the door won't open. What might be the problem?

: Does it automatically go
: through and open-close-open cycle at power up
: for testing purposes? An answer to this
: could give me more clues as to why this is
: happening.

I'm sorry but I don't know how the control on your range was designed to operate. If you get an owner's manual for it, it may say what operations are to be expected.

: Why would
: manufacturers add in the extra hardware to
: lock a door during self clean? Just how hot
: does it get in there?

During a self clean cycle, the temperature can reach 850-900°F, older models got closer to 950°F.

Dan O.
Appliance411

Kenmore 790.7572899 Door Switch