Keep Warm mode and Natural Pressure Release
In my Instant Pot FAQ, I have the following question:
Q: What about natural pressure release? When the Instant Pot finishes cooking, it switches to Warming mode – is that OK with a natural pressure release? Or should I cancel it?
A: Cancel warming mode to speed up natural pressure release.
I was reading the Instant Pot Community Facebook group, and saw a heated debate: Keep Warm and Natural Pressure Release. One side was strongly in the “warming mode doesn’t matter” camp, the other was in the “turn warming mode off” group – and used my FAQ post as evidence.
After reading the debate, I started to wonder – am I wrong about warming mode? I assumed that turning off the heat would speed up the natural release – that the pot would lose heat quicker without any heat being added by warming mode.1 The argument against cancelling Keep Warm mode is the pot’s thermostat. Warming mode keeps the temperature between 145°F and 172°F, so it won’t turn the heat on until the temperature drops to 145°F. That’s well below the temperature where pressure will release.
I ran a quick test – I set my IP-Duo and IP-Smart next to each other on the counter, added a quart of water to each, set them for 3 minutes of high pressure cooking, and waited for it to finish. They both came up to pressure and counted down the three minutes at about the same time. I cancelled the Keep Warm mode on the IP-Smart, and waited for the pressure indicators to drop. Much to my surprise, the IP-Duo finished manual pressure release about five minutes before the IP-Smart!
But…is that a valid test? Maybe there is something about the IP-Smart that slows down cooling. To reduce the variables, I ran the test over and over again with my IP-Duo, a quart of water at high pressure for 3 minutes, and alternated leaving Keep Warm mode on and off.
Sitting and watching natural pressure release is only slightly less interesting than watching grass grow. So, instead of babysitting each run, I set my Phone on a tripod and filmed it using time-lapse video mode. Here are the time-lapse videos from the third run, side by side:
You can see them finish within a minute of each other – this is consistent across all the tests. Sometimes Keep Warm mode finishes first, sometimes cancelling it does – but the difference between them was always less than a minute, and it kept moving around as to which was faster. 2
In summary…
Keep Warm mode doesn’t affect natural pressure release. It finishes at about the same time either way, so don’t bother canceling it. I was wrong in my Instant Pot FAQ; I’m sorry I gave you bad information. (And, of course, I updated the FAQ to match this new info.)
Thank you for taking the time to figure this out for me! It is frustrating that the instruction manual is not more specific.
Wow-this was a super-helpful post and I really appreciate your approach and sharing the results with everyone. I agree with previous poster that the IP instruction manuals are woefully lacking in specificity. Thanks a bunch.
Every time my recipe calls for natural release, after the pressure cooker is done it just turns off. The pressure release countdown never turns on at all. Doesn’t turn to warm mode, just shuts off entirely. I even watched it for 10 min and nothing happened. Am I missing something? Is the pressure release happening, just not the count down? Help? 😂
What kind of pressure cooker? Make and model?
Thank you so much for taking all that time to explore this empirically. I was really wondering why some recipes said to turn the Instant Pot off, while others allowed the natural release to happen on keep warm. I thought it had something to do with whether or not the meat would overcook or get dry or whatever the reason may have been. Thank you for solving that it’s irrelevant. I can leave the Instant Pot on because, as Ed Bragg pointed out, I want the count up for the natural release. Way to go, Mike! Second time your site has come through for me. (Awesome cheesecakes, by the way!)
You’re welcome!
thank you for this! tip given,
and with heat on, you get the bonus of the timer function!
Thanks very good info!
Thank you for your time and trying to answer this question. Appreciate all your info.
How great to have this very vital question and have such a valid response. I think my life can go on enjoying my Instant Pot even more. Trying a bread pudding this afternoon and will just let the keep warm mode take care of the natural release.
Great information ! Thanks a lot !
Thanks, Dad!
You’re welcome!
I’ve been searching for an answer to this question for about a year. Your detailed and well reasoned explanation makes perfect sense. Thank you!
You’re welcome!
Thanks for testing I too am a new user and thought I read you had to cancel keep warm so Im glad to know it is not necessary
Love that there’s even a dad who’s got this figured out …Whoever used to think that only Mom’s knew all about cooking appliances were not really noticing how many great dads there out there today.. Keep it up Thanks for your “dads cook dinner.com Wishing you the Best…
from Longmont Colorado…