This detailed video on the water test is for Instant Pot Ultra owners. Most of the videos for the Instant Pot on Youtube are showing the Duo model. The controls are different.
The water test is for a couple things. Some people recommend to run the water test when you first get your Instant Pot to make sure it is working properly before cooking your first meal in it. The other is for those new to pressure cookers and just to run a simple cycle to get use to the operational procedures. Also I ran this sterilize cycle when I first got my Instant Pot to make sure it was clean before using.
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