When you're taking your jars out of the canner, sometimes they will immediately start popping. Generally, you'll put them on the counter and after a few minutes, they'll start popping. The popping sound when canning is a good thing IF it indicates that this lid is popping down.

What do you do if your canning jars don't pop?

In the event a lid does fail to seal, you can reprocess the canned foods. The first way to do this is to remove the lid and check the jar's surface for nicks. If that's the issue, change the jar, add a new lid, and wait 24 hours before reprocessing.

Do canning jars always pop?

The familiar pop of a two-piece canning jar ensures an airtight seal. ... Don't worry, though, if you don't hear your jars popping right away -- it can sometimes take longer, and some jars even seal without a pop.