I don't do that kind of cooking on mine, but I think would want to get one with the largest possible hobs (on mine, I can definitely use a stockpot that is larger than the largest hob, as long as it conducts heat well).

I don't think the other two issues are real issues - as for weight, that would be the same issue on any radiant heat/glass top cooktop - you're not dropping the pot, are you :-)? As for damaging the element, as far as. I know, the element heats up the pot, nothing the pot does affects the element.

You can't use a standard old time water bath canner - they do not work on induction. You have to modify a pot that can be used on induction or buy a canner specifically for induction (they do exist). This was one reason I was not that enthusiastic about induction.

We can and often have two water bath canners going simultaneously along with sugar water, and blanching water. I was concerned about breaking/scratching an induction cooktop because I'm not a gentle cook and because the canners with all that water are heavy. I was also concerned that having that many burners going simultaneously all day long may not be sustainable. You would definitely need more than a 30" cooktop if you had more than one water bath canner going.

My mom replaced her coil cooktop with induction and bought an induction canner. We haven't yet canned on it. It will definitely slow things down and we've talked about getting an outdoor gas cooktop (that come in up to 60k burners) so we can have two canners going. This might work. She is happy with induction (gas not available in her area). After cooking on her induction cook top though, I'm happy I opted for gas.

The manufacturer might recommend not putting a huge amount of weight on the cooktop (I think that was true for the old ceramic topped electrics) so verify that.

I'm not hardcore and just used a cheap Graniteware canner for my limited HWB canning.

To be honest, in my experience with 2 different induction cooktops, neither cared a darn bit what size pan I used (unless I was trying to use a 5" saucepan and didn't center it perrrrfectly).

sanguinepenguin: welcome to the conversations.

1. Canning bad for induction? Nah. Well, some induction manufacturers put CYA nonsense in their user manuals such as edicts prohibiting canning. Most do not. Basically, before you buy an induction range or cooktop, download and read the manuals for the models you are checking. When you find a user manual that says "no canning," that's either something somebody in risk management told them to say or else the company has skimped on materials and is selling a cheap and fragile product. Cross that model off the list and move on to another maker's products. Heck, you can find all sorts of claptrap in the most unexpected places. The user manual for Viking's induction range -- as a heavy-duty a unit as you could expect to find --- used to have a Chicken-Little proscription against the use of any cast-iron pans at all. Somebody said cast iron would damage the system because cast iron pans retain heat and, lord knows, we can't have hot pans on our stove, can we? :>))

So, in a sense, this is a problem that, as you put it, is "easily solved by going with one brand of induction over another."

FWIW, when I was stove shopping three years ago, GE's customer service reps told me that the company was fine with using large canning kettles but recommended that you avoid loading a burner with pot with water and jars weighing over 50 pounds. I think I've read that Electrolux has similar recommendations for its Frigidaire (and Kenmore clone) ranges.

2. Problems with "large canning pots" on induction being too large for the burners? There is some urban legend stuff that gets that gets mixed into these discussions and makes things confusing on this subject. It sorts out pretty easily into the following categories:

(a) There is nothing special about "induction" canning kettles. They are just made from a magnetic stainless steel. They are cheap and readily available. Got my 5 gallon pots from Walmart almost two decades ago. They work fine on gas as well as coil and induction and, IIRC, were less expensive than the aluminum models.

(b) Obviously, you can't use large aluminum canners like the All-American models. The key word here is "aluminum" not "large." Large or small, no aluminum pot will work on induction. Induction only works with ferro-magnetic metals.

It is possible to find aluminum pots and pans with a ferro-magnetic disk in the base, but I have to say that I've never seen that on a canning kettle or 5-gallon (or larger) stock pot. Some folks suggest getting one of the induction converter disks and putting your aluminum canning kettle on that. It might be workable with a large induction burner, but I found it to be a bust the time I tried it with an 1800 watt burner. Too slow for words.

(c) Even Graniteware kettles work well for water bath canning on induction. Occasionally, you still see folks posting that GE or "somebody" supposedly says not...

JWVideo's answer is excellent, but I'll add one point.

Summary:

• Pots must be steel/iron, not aluminum
• Useful (large) pressure canners are aluminum and won't work
• Most induction elements are rated for pots up to an inch beyond the ring, but they'll still heat the centers of larger pots
• While you can put a large, full pot on a glass surface, there is a limit that a cast iron grate does not have

What wasn't mentioned is that there is an issue with ridges, which the classic Graniteware water bath canning pot has. The pot will heat up with an uneven bottom, but just as the glass underneath gets hot from the hot pot, so too does the air underneath. When there are ridges that hot air pocket can potentially lead to cracking the glass. You're warned very sternly by all the manufacturers not to do it.

You also need to be careful with spilled sugar. If it (or salt) is dragged across a glass surface, such as when sliding a heavy pot, it can etch the surface, which can lead to a crack, same as when you etch with a glass cutter and tapping makes it crack through.

I waterbath canned some marmalade in small jars in a five quart cast iron dutch oven on induction. It worked fine. :) But for the kind of heavy duty use you describe, induction might not be the best choice.

I got both induction and gas, under one hood, and am very pleased to have both. Perhaps this is something you might consider too. A moderate sized induction cooktop for family cooking, as well as blanching and boiling. A powerful gas burner, on reinforced supports, for the canning pot, woks, etc., which can be extra space for regular cooking, too.

I am not a serious canner but did a bit on my Wolfie and worked fine. It would be good to figure out the wiring under the cooktop so you don't put the pot over the wires.

I have a cooktop that is flat and includes three radiant and one halogen burner. The flat surface is not stressed by the pressure canner and is easy to clean.

They didn't sell induction here at the time (15 years ago) otherwise I would have bought it and a single radiant instead. For now I have the reverse, a single induction burner to the side- which I use for water bath.

Induction will save you loads of power costs for everyday.

You don't can every day so wouldn't it make sense to get one of those portable/plug single radiant burners for when you want to pressure can?