Mirro Canner M-0512

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Assistant Cook
Sep 1, 2022
Hi All,
I bought this cooker last year and have used it for the first time yesterday. Capacity is 7 Quart jars. I used an outdoor Carolina cooker stove with a propane tank.
I followed the instructions in the user manual.I used 2 quarts of water in the cooker, before adding 7 quarts of prepared green beans. I stayed right with the canner through the whole process. After 10 mins of steam venting, I placed the PRESSURE CONTROL on the steam vent. There was a tremendous amount of steam coming out of the right handle. So much so that it appears to have damaged the handle. As soon as the pressure control started to jiggle, the steam from the handle stopped.

I think this is where the spring safety is located. I do not want to cause any more damage to the handle. Should I let the canner steam vent for longer than 10 mins? Did placing the pressure control on the steam vent cause the steam to exit via the handle? Any suggestions will be welcome.
When my pressure canner's rubber gasket is misplaced or not quite in the groove, it will vent on one side or another of the lid. I take the lid off, move the gasket around in the groove to get it in the groove equally on on all sides. Often, the first time I run it, this will happen, but once it has had lots of steam/heat on it, it doesn't do that anymore for the rest of the season. You could try lubricating it with vaseline if this is the first time you've used it.

I don't have the model or type you mentioned. I don't know if it is damaging the handle. I don't know anything about a spring.

When you placed the pressure control jiggler on the vent the pressure built up until it reached the specified amount of pressure (say, 15 lbs) (jiggle), then the pressure control started to rock or vent or jiggle, and this took the pressure off the lid/gasket, so it doesn't vent on the side. (steam can be so hot you can't see it, but you can check for it with your hand (carefully), or with a mirror or glass, to see the steam)

Go ahead and look at the gasket and make sure it is on the lid equally all the way around. Put in 2 qts of water, start it up, without the jiggler, let it vent and see if steam is still coming out by the handle.
No you don't need to vent for longer than 10 minutes.
With my pressure canner, once it's been venting for 5 or 6 minutes, it will start to have pressure on it (only a couple lbs of pressure). I know this because it has a gauge and a vent. Yours might have a vent without a gauge on it, but the same holds true.

The jiggler, once placed on the vent will let the pressure go UP, until the specified pressure of 15 lbs is met(or whatever lbs the jiggler is set to jiggle). Then it jiggles to let off steam and keep the pressure in the canner stable.
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Thanks for the suggestion.. I will check the seal and test the cooker empty. I think I will also use vaseline on it. Mom always uses vaseline. I just thought I did not need to since it was a never used before cooker.

One thing I have always done is to store the gasket on the outside of the pot. Keeps is nicely round and helps prevent it from shrinking.

Katie, I have an old magic chef (like a presto, like many names it goes under). Do you know if it would work on that? I haven't done it because I'm worried about breaking it.
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