Help to troubleshoot cause of problem with Kenmore (GE?) range

[floridaguy]

We have a 30-yr old Kenmore (I believe GE) range model 911.4638810. I just perused one of your inactive forums regarding how various ranges used the lower vs upper element in baking and now understand that our range should use the lower element plus the upper element at 50% voltage. Apparently, our range is using the upper element erratically or not at all as nothing is browning properly. The upper element seems to work properly in Broil. Would you have any advice as to the likely cause of this problem and what should be replaced to fix it? We might keep the old range a while longer if the fix isn't too expensive and can be done by a generally handy amateur (me). Thanks for any advice that you can provide.

 

[panthera]

it will take a few days or so before the experts chime in

So I'll give you a few things which I have found to be useful over time:

1) GE includes a service diagram with all their appliances. May be glued to the back of the stove or tucked away in the lower drawer or the control panel - but it will be there.

2) If both elements are working properly by themselves (you can check the ohm readings, may be below 20 or even below 10 but not 0), then there's really only two possible causes - a failure in the oven control system or thermostat.

I may be wrong, but there only appears to be a conventional, mechanical thermostat/control in this oven.

 

So, it may be that this oven does not necessarily run the bake and broil in series (50% voltage). Not all did.

 

Can you unplug the stove, take the panel off the back and check out Range/Stove/Oven Temperature Control Thermostat WB21X489? Are the wires firmly attached and not loose or burnt? follow them down  to the broiler and bake elements.  Does anything smell burnt or weird? The part is still available, but pricey - nearly $300.00 with shipping. At that point, getting a used one for a 30 year old stove isn't a bad idea. 

 

Check the continuity on that device on all the settings. If you don't know how to do this, let us know. It's easy to learn and only takes one of the Harbor Freight meters they're always giving away or selling for less than $10.00.

 

This will at least get you through to knowing what is working and what may not be. Super important that the stove be disconnected for all these measurements, not just for your safety but also so you don't get false readings. A purely electro-mechanical system, it's reliable and should be fairly easy to diagnose.

 

 

 

 

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[floridaguy]

Thanks, Panthera. I am recovering from back surgery and still am limited on physical activity. I will do the checks that you suggested as soon as I am able - if we can stand using the oven as it is that long! Great suggestions. As you said, this should show what's working and what isn't. I will check impedance on both elements, but I believe that each is working. The oven does reach set temperature in Bake with only the lower element, and the upper element does come on in Broil. The oven used to brown well in Bake but now browns not at all. Thanks!

 

[kenwashesmonday]

The link below shows Kenmore code 911 as being manufacture by Roper.

Sears Appliance Manufacturing Codes | Appliance Aid

www.applianceaid.com

 

[floridaguy]

Kenwashesmonday's, thanks for pointing this out. I ordered replacement surface elements a few years ago, and the supplier cross-referenced my Kenmore part numbers to WBxxxxxx part numbers, which another source identified as GE. They fit fine, so I mistakenly assumed the range was GE.

I located a wiring diagram for the range and have attached it here. By my reading, the upper oven element is not used in Bake mode - only in Broil. In that case, how to explain that nothing browns in Bake mode any longer although bake times seem to be about right?

I need to see if I still have an oven thermometer and check the temperature.

Thanks!

 

[panthera]

The Browning is interesting

And, if the bake times haven't changed then it does raise many questions.

So - no browning could be caused by a a few things besides time/temperature.

If the moisture in the oven is not escaping out the vent, that might account for it?

Have you checked that? Is it possible that there was once a reflective shield under the broiler which is no longer there or a flare up when broiling darkened it to the point it no longer works? An overly aggressive oven cleaner ate through much of it or discoloured it?

 

Could a rack have been lowered one notch - makes a gigantic difference or, perhaps a different set of baking pans is being used? I'm sure you'd have thought of this, but asking for the sake of completeness.

 

As to GE versus Whirlpool, they do often use the same parts in some lines. All original Whirlpool parts will say 'FSP' somewhere on them. Roper is a very old, very well respected oven maker which was bought by Whirlpool for their technology many years ago. 

 

[floridaguy]

Panthera - I certainly will check the vent. I don't see a reflective shield under the broiler and do not see this part in the user manual's parts diagram. We certainly have used various pans and sheets and different rack heights through the years, but the lack of browning that we have seen in recent months seems to go way beyond what those variables could cause. Interesting information on Roper. I knew the name but not the story.

Could you verify my reading of the wiring diagram to confirm that only the lower element is used in Bake setting?

Thanks for your help.

 

[panthera]

Yes, I can confirm that

Here's a screenshot of your service sheet - the settings for the oven temperature control.

That there is only an 'L1' and not an "L1" and an "L2" suggests a super simple control (more options with both, but irrelevant as rarely implemented).

The PL means Pilot Light, so you should have a light which comes on when heating and goes off when the temperature in the oven has been reached?

The BK is the bake element.

The BR is the broil element.

As you can see, there is never an "X" in both columns for BK AND BR at any time, just for PL and one or the other, separately.

This is confirmation that we are not working with both elements in tandem, either in series (110V) or parallel or something else.

 

Here are two other things to check, not that I consider either likely:

a) Could it be that your house voltage rose to 220/240V from 208V? Your utility company could tell you. It wouldn't make that big a difference in heating times, so you might not notice it, but it would definitely lead to shorter baking times - and that could result in lessened browning.

b) Is it possible that a seal between the door and the oven is gone or has failed, or the door has slightly warped, reducing the heat at the top? Or, truly unusual but trying to think out of the box, did the door or the seal get tighter, and there's more moisture in the oven or a shorter baking time?

 

Try this. Bake some cookies, spread out as far apart on a baking sheet from each other as possible on the rack height at which you usually bake. Do they all come out evenly in the baking pan? 

 

 

[floridaguy]

Thanks for your confirmation and good suggestions. I have a number of things to check and will get on with it. I'll let you know what pans out.

Again, thanks for your help. I am impressed how folks are willing to take their time to share their knowledge to help others.

 

[panthera]

Happily,

There are several people here who really know these things inside out. If we can't figure it out together, one of them will no doubt chime in at some point.

Here's another improbable to check - is it possible that the baking element was knocked out of alignment with the spacers during cleaning? It isn't supposed to touch the bottom of the oven at any point. Those spacers can sometimes get knocked loose, whether they are wire or steel pins or ceramic.

In the same light - could the thermostat bulb have come loose from its bracket within the oven? If it's in the wrong position, it might well be telling the thermostatic control that it's warmer in the oven than it really is?

 

 

 

[circlew]

Roper and GE

In 1988 GE acquired the Roper range manufacturing facilities, while the Roper trademark went to Whirlpool. As a result, some Roper and Roper sourced Kenmore ranges made after that time will have parts supplied through GE.

 

[panthera]

Tom, thanks!

I didn't know that!

Today, Roper is often the value brand for Whirlpool, like 'Estate' or 'Kirkland'.

Same quality as the equivalent other Whirlpool brands, just way cheaper.

 

[mattl]

Another options I did not see mentioned - is the oven temp correct?  350 may not be 350 in the oven if the thermostat needs adjustment.  Many older ovens calibrated the oven temp by rotating the outer dial on the temp knob.  If you look at the back side many have tick marks as a guide for adjustment.  Some knobs are friction based , other have a set screw.  If the knob was pulled for cleaning it's possible it's miss adjusted.  Get a decent oven thermometer and check the temp. 

 

I've adjusted all my ovens using the temp probe that came with one of my VOMs.  Even my high end Electrolux wall oven was off by a good margin. Just so you know, there is a temp swing, no oven is a constant 350 or what ever it's set at.  It may go as high as 370+ and as low as 325 when set at 350.  It took me a bit of time to tame the Electrolux, the 2 Frigidaire ovens in my other range were a bit easier to manage being mechanical rather that electronic.

 

[panthera]

Good point, Matt

I thought of the sensor in the oven or the heating element being knocked, didn't occur to me that the regulator might have gone out of tune.

 

 

[floridaguy]

Will check temperature setting

Thanks for this good advice. Can't find my old oven thermometer but will get one so I can check. Any recommendations for an oven thermometer that I could pick up at Lowes or Home Depot, or do I need to go to a specialty supplier or Amazon?

 

[mattl]

I think in this case a generic thermometer will do.

 

[perc-o-prince]

I think in this case a generic thermometer will do.

$0.02 worth...

If you can, order a digital one off of Amazon, eBay..... they are usually better for testing than the dial analog models. I say ordering as I went nuts looking for one locally about a year back and couldn't find one in-store anywhere (disclaimer: did not check mall specialty stores). We would have a lot of service calls (Miele) where the customer was using a dial thermometer and not waiting for it to catch up to the true temp. If they waited another 10-15 minutes after the unit said it reached temp, the dial had caught up. Our digital meters were generally less than half a minute behind the oven's internal sensors. Also keep in mind that the dial meter won't really reflect the temp swing Matt referenced. I've found electric ovens to generally have a tighter swing than gas, but it's still up to 20-25F each way.

I always asked them if their cooking times had changed. If not, there was generally nothing wrong and it was a false sense of inaccuracy caused by the oven thermometer.

As for your browning issues, I can't think of anything other than what's been mentioned by those who have a lot more experience than I!

Chuck

 

[mattl]

Good point Chuck, I know to let the oven stabilize it's temp when using an analog thermometer but didn't think to mention it.  Even when I use the digital meter I let the oven sit a good 30 minutes after it reaches it's set temp before doing any adjustments.  That way all the metal and other components should be at a stable temp and the elements have cycled on and off a fair number of times. Might be overkill but I'm not on the clock.

 

[eronie]

Most grocery stores carry the analog thermometer.