You'll find the discussions on hard water problems in the Causes and Solutions for Problems sections at NCHFP linked below. Hard water is primarily a problem with pickling where is causes cloudy water and discoloration problems. It isn't a risky thing per se, just an undesirable appearance issue but it can be avoided by using bottled water if your's is especially hard or you can boil the water first for 15 mins. then let it stand covered for 24 hours and skim off the residue. That will remove much of the hard minerals in the water. Adding a good 'glug' of vinegar to the canner/PC water eliminates the build-up on the canner and the jars and you can use either Lime Away or CLR to remove any build-up deposits in the canners. Vinegar works too. Dave Here is a link that might be useful: NCHFP - Problems

This is the bottom of the 18 qt, but it's the same. 8 inch raised section fits well on glass or coil round burner, not sure how it will be on your 6 inch (square). It will fit, but depending on how close the center of that burner is to the edge of the stove it will overhang just like your 14" stockpot does. I can't speak to whether you could set this centered between the burners which you said span 15" - it might not be stable and I don't know how 2 flames on the sides (lapping up the sides? Unless you can control just the left or right ring of each burner - I saw a camp stove like that, might have been at Northern Tool or Amazon) and cool spot in the middle would affect function, or whether it would warp. Be sure to ask the rep tomorrow.

I have two All American pressure canners that are identical to the one that was pictured. In my opinion they are the finest pressure canners ever made. I have never had one problem of any kind with them. The gauges are accurate, and I have them tested at irregular intervals. As much as I use them, I have NO problem maintaining whatever pressure I want. (yes, I confirm that the guage is at the correct pressure by looking) When I am canning, that is the only thing I do except clean in the kitchen and stuff like that. Listening to jiggling or bouncing weights is just not my bag. :) Incidentally, they can be used for canning using a hot water bath, as well. Just don't put the lid on them. Have fun.

As Carol said, and as discussed here often, Presto Customer service reps are notorious for giving out unreliable info. Just as canner manuals are notorious for being outdated and misleading an are not recommended as a source for information. Not only has NCHFP vetted and approved the use of the 3 piece weight set (50332) but so have many users. A number of us here use it and have for years with no issues whatsoever. It works on all but the most ancient of the canner models. And it even works on them if you change the vent pipe too. Much of the confusion stems from the labels used interchangeably and mis-understood. There is no difference between a "weight" and a "pressure regulator". They are both "weights" that regulate the pressure inside the canner by rocking and allowing excess steam to escape. If you wanted to process everything at 15 lbs. then you could just use the pressure regulator/weight that comes with the canner. But you don't want to do everything at 15 lbs. So you buy part 50332 and process at the weight of 5-10-15 lbs. as needed. ajsmama - your only real problem is your stove and whether it will work with the PC or against it. Some do and some don't. A 10" burner is standard and causes no problems with the canner UNLESS it is one that cycles off and on and that is a stove brand issue, not a canner issue. You can test to see if that happens by simply boiling water in any 12" diameter pot or even a standard 12" skillet on the burner. If it cycles while using a standard skillet then it will cyle off and on with any brand of canner. As to where to buy the canner and the weight set - that is your choice. Please take the time to read through all the previous discussions here on '50332' and 'Presto canner' as this has all be hashed out soooo many times here that all those testimonials will reassure you that what we are saying is true. Dave PS: same holds true for all the 'glass top stove' and smooth top stove' discussions.