For a pressure canner to can food and kill bacteria spores, it requires adequate pressure and heat. If you take off the canner when it has not pressurized adequately, you may not get good results.
That’s why many users keep asking how long does it take a pressure canner to build pressure? We have given a detailed explanation right below.
How Long Does it Take Pressure to Build in a Pressure Canner?
Two factors that determine how long your pressure canner will pressurize are the amount of steam in it and the altitude of your location. Both of them work against pressure.
The more the air in the pressure canner, the longer it will take pressure to build up. That is why you must allow the canner to vent for about 10 -15 minutes before you set the regulator on the lid.
Venting simply means allowing steam to escape. On the other hand, the higher the altitude of your location the longer it will take pressure to build up in your canner.
In other words, if it takes your pressure canner about 5 minutes to build pressure at 1000 feet above sea level, it will take the same canner longer to build pressure at an altitude of 1200 feet.
Nevertheless, pressure builds up in 5-10 minutes after venting. Now let’s do the mathematics. It takes 10-15 minutes to vent and 5-10 minutes to pressurize. So, we can say that it will take your pressure canner about 15 – 25 minutes to pressurize.
Remember to allow your canner to vent. When you cover it with the lid, don’t set the regulator on it yet. Allow the steam to escape through the opening on the lid for about 10-15 minutes. After that, you can set the regulator. If you don’t allow it to vent, it may take a very long time to pressurize.