Canning on a glass top stove

The stove that came with the house is, I'm guessing, about fifteen years old.  It was an Amana glass top electric model and served us well for normal household use, and I even managed to use it for both water bath and pressure canning of many jars of food.

I know, I know.  Everyone says that you're not supposed to can on the glass cook tops because of the weight of the canner.  But I did it for years with no ill effects, although it could have been because I was just a lucky duck.  Even though I was able to successfully bring the canner up to heat / pressure, it did seem to take an long time.  This could have been because my element was on it's way out, or it could have been because the wattage just wasn't enough to keep up the temperature.

I've also noticed that unlike a gas range, which has the flame constantly going, the electric ranges seem to shut on and off, if even for just a few seconds.  I'm not sure if that's a safety thing or a mechanical thing, but it must effect the amount of heat being transferred to the pot.

That's another thing you must have in order to safely and effectively can; a pot with a flat bottom.  I admit, I still use some of my Grandma's Revereware (with it's very noticeable wobble) for cooking, but not for things that I need to get really hot, like jams or candies or when I need to get something to boil quickly.

One of the major selling points of the new stove was the fact that it had 3,000-watt dual element in addition to the standard 2,400-watt large element.  In theory, if I could bring my old 2,400-watt element to work with the pressure canner, the new dual element would work even faster.....and, in theory, still use the other element for a second canner.  If I didn't end up cracking the glass top with all the weight.  And that is, I believe, the major reason that people are hesitant to can on top of their glass top stove.

Although I didn't get as scientific as Yukon Mike does on some of his posts (I won't say anal, but come on, that's what it is, admit it Mike!) I did do some figuring and came up with the weight of a full canner.

I have a Presto 23-quart aluminum pressure canner / cooker.  It weighs exactly 9 pounds.  Three quarts of water (the recommended minimum amount for pressure canning) weighs 6 pounds.  Seven full quart jars with bands & lids (I just filled them with water) weighs 19.25 pounds.  So a full pressure canner weighs....hold on a second.....

I would think most of my readers (sans Christine)
know what this is.  I'm showing our age, aren't I?

....the canner and contents weighs 34.25 pounds.  So is this an acceptable load for the top of my cook stove.  Would it be safe to put both of my canners on the stove?

According to my Whirlpool Electric Double Oven Range manual the "Recommended Use" for the Dual Elements list 1) Large diameter cookware, 2) Large quantities of food, and most importantly 3) Home canning.  There is even a section titled "Home Canning" which states that the canner should be centered on the largest cooking surface or element, and should not extend more than 1/2" beyond the surface cooking area.  Technically, the large element (in addition to the Dual-Element) meets this criteria.  But even though it seems as if I could use both canners on the stove at the same time, I don't know if the glass top can hold close to seventy pounds.

I've read the entire manual and haven't found any weight restrictions for the cooking surface.  I did, however, find a section called "Sabbath Mode".  Apparently there is a setting which conforms to Star-K Jewish Sabbath requirements for baking.  Hmmm.  Who would'a thunk it.  Anyways.....

I'm going to send an email to Whirlpool and see if I can get any information on the load limit for the stove top.  When and if I get a reply, I'll update this post to include it.  And maybe I'll even bake some bagels and try out that "Sabbath Mode".....it is Sunday, after all.