As others have said you can use the pressure canner if it allows 2 inches of boiling water above the jars. Be very careful, however. Two years ago I was using this method and had locked down the lid leaving the vent open as JodieMo suggested earlier. A small amount of pressure had built up and when I removed the lid, the superheated water exploded up out of the canner and burned me quite badly. I still have the scars to prove it. This was a very old canner (it has since been retired) and did not contain the pressure lock that modern Presto models have. However, I will never again lock a pressure cooker lid down for boiling water processing. Either remove the seal or search for a lid that fits the pot.

Some different terminology for clarification - they are weights or gauges, not weighted gauges, ok? Some models have only a gauge, some only a weight or set of weights, and some have both a gauge and a weight set. No the weights never go bad assuming they are the right one for the model/brand of canner. However the gauges do go bad - some are off by several pounds right out of the box - which is why having them tested/recalibrated annually is so strongly recommended. If you want to use the 12 qt. Presto then we usually suggest you buy the 3 piece weight for it rather than rely on the gauge unless of course you are at an altitude where you have to can everything at 15 lbs. in which case you can use the 15.5 lb counterweight on it. I am assuming it will hold the 4 quart jars minimum to qualify as a pressure canner rather than just a pressure cooker? Personally of the 3 I'd use the 22 quart Mirro given its size and because gauges just can't be trusted. Dave

Is this a new idea that it is not safe? No not at all. My 1972 edition of the BBB (oldest one I have) discusses the importance of canner size and its relevance to the processing times but if I recall correctly the specific size guideline was in either the 1984 USDA or the 1986 rules revisions. Historically small pressure cookers, first released in late 1930's were never intended or used for canning. When pressure canners were first developed in the early 1900's and made available to the public they were huge things so the issue of trying to can in a small pressure cooker seldom came up and most home canners already had big canners. It is your choice of course, your risk to take, as long as you understand that USDA makes it very clear that the published processing times are valid only if one uses a canner that will hold and process at least 4 quart jars. Those published times are computed based on the amount of time it takes for a canner that size to come up to pressure and to cool down. The Mirro 12 quart is the smallest recommended. Otherwise the foods are considered UNDER-processed. Dave

There are plenty of tomato recipes you can water-bath too, however. Some of us who have only water-bath canners manage to put up quite a few tomatoes! But the good news is you can use your pressure canner as a BWB canner if you decide you want to can some recipes that can be done that way. The resources you mentioned (BBB and the NCHP) are great ones, with up-to-date safety guidelines. They'll tell you for each recipe whether it should be pressure canned or BWB canned or whether you have a choice. BWB is used for high-acid things: fruit in syrup, jams and jellies, pickles, some tomato and other recipes that have appropriate acid amounts. Pressure canners allow you to do low acid things like beans, other vegetables, prepared soups and stews, even with meat in them, and a wider range of tomato recipes. Try both approaches! See what you like! Z