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- An Instant Pot only hisses faintly as it builds up pressure, then again at a short interval after reaching maximum pressure to release any excess steam causing and caused by overheating of the pot. This is necessary to maintain the correct internal temperature. During all other periods of the cooking cycle, your Instant Pot should be silent, with only the sound of the motor and bubbling within the pot audible.
- Every last part of your Instant Pot can be replaced, even the base, so always enquire for replacement parts or advice if you suspect a fault to be present.
- Key Takeaways
- Instant Pot Hissing During Cooking – Is It Safe?
- Why An Instant Pot Hisses As It Builds Up Pressure
- What Type Of Instant Pot Hissing Is Normal?
- Test The Seal With A Simple Water Test
- Correcting A Noisy Hiss
- Okay, So What If It Won’t Stop Hissing?
- Instant Pot Hissing – Frequently Asked Questions
For those new to an Instant Pot or the world of pressure cooking, a hissing noise coming from a brand-new machine often incites frustration. Even for more experienced cooks, knowing exactly when an Instant Pot hissing noise is normal can be confusing. We’ll be taking you through a look at Instant Pot hissing and showing you exactly how to determine when hissing and steaming are safe and how to rectify any potential pitfalls that could be causing the problem.
Instant Pot Hissing During Cooking – Is It Safe?
If you want to see just how scary the sound of hissing can be, just bring a kitty cat within any audible distance of an instant pot or pressure cooker. Yes, the sound can be intimidating, but in almost all cases, it is perfectly normal, at least for a short duration of the cooking period. Hissing is safe and to be expected during pressurization and for short bouts of venting after pressure is reached to regulate the temperature. The hissing sound is also inescapable during both natural and quick release. After all, the pressure has to drop before you can open the pot. However, if your Instant Pot is hissing and steaming constantly while cooking and it never builds up pressure causing the float valve to lift, then it’s not sealing correctly, and it’s not safe to use.
Why An Instant Pot Hisses As It Builds Up Pressure
The hissing sound that every Instant Pot emits during pressurization and depressurization is caused by the release of steam. Until the Instant Pot (or pressure cooker) builds up enough internal heat and consequent pressure to sustain the desired cooking temperature, a slight quantity of the steam build-up on the way to pressurization is lost through the valve and vents. An Instant Pot will then again emit an even sharper, louder hissing sound when the internal temperature and pressure are too high, thereby forcing out steam out through the vents and creating the shrill sound.
What Type Of Instant Pot Hissing Is Normal?
Every Instant Pot will hiss periodically as it balances pressure. Any prolonged unceasing hissing is a surefire sign that something is wrong. Similarly, if the hissing of your pot follows absolutely no pattern, this is also a cause for concern but typically one pointing to an incorrect moisture level or overfilling. Every Instant Pot will take roughly the same period of time to attain a certain degree of pressurization, at which point the excess triggers a venting process. It is only during the initial pressurization phase that a faint hiss will be heard, and during venting when the hissing will be sharp and loud. At all other times of the cooking cycle, other than the natural and quick release after cooking, your Instant Pot should be near-silent.
Is Your Instant Pot Actually Reaching Pressure?
The very first thing you should do is watch the pot and see if it actually pressurizes. This is indicated by the float valve rising. An Instant Pot can take anything between 5 and 50 minutes to reach full pressure, at which point it will cause the float valve to lift and lock the pot. After this point, steam may be flushed out periodically as the internal temperature gets too high. If your Instant Pot’s valve never rises, it will always emit a hissing sound due to an ongoing escaping of pressure.
Test The Seal With A Simple Water Test
Instant Pot details a basic water test to be performed on every unit prior to cooking any food in it. This shows that the appliance seals and therefore ensures safe functionality while pointing out any possible problems through the effects exhibited through testing.
Here are the basic steps to follow:
- Plug the Instant Pot in.
- Add three cups of water to the inner pot.
- Insert the inner pot into the Instant Pot’s base.
- Confirm the secure alignment fitment of the sealing ring.
- Close your Instant Pot and turn the lid clockwise to lock it into position.
- Seal the steam release valve.
- Pressure cook on ‘Ultra’ or the highest setting for 5 minutes.
- Opt for either natural or quick release at your discretion.
Look and listen carefully to your Instant Pot during the water test. A faint hissing should be heard for about 5 minutes. This is the period when the pot builds up pressure and is affected by the temperature, liquid level, and fullness of the pot during normal cooking conditions. Steam will be escaping from the valve and emitting a sound until the pot pressurizes. Once maximum pressure is reached, the float valve will rise, the lid will lock totally, and the timer will start. At this point, the Instant Pot becomes silent, and no steam should be escaping from the valve or sides. If it is, there’s a fault which is most likely the sealing ring or a worn valve, but potentially the sensor or contorted shape of a well-used pot itself.
Correcting A Noisy Hiss
There are several steps to follow when troubleshooting a troublesome hiss. Work through these steps to figure out what the problem is and how to solve it. Once you’ve sorted out your worries and confirmed that your device is working, you may want to give some of the brilliant Instant Pot cookbooks from our top list a look. There’s no faster, more reliable way to a foolproof, mouthwatering meal.
Inspect And Align The Gasket/Seal
If your Instant Pot doesn’t seal correctly, it is going to emit a faint but sharp hissing and the steam will be escaping from the sides and valve. .Check the alignment of the seal within the lid. If it is fitted correctly, but the sound doesn’t stop, then the gasket itself has become brittle or contorted after losing integrity through repeated use and therefore needs to be replaced. Without cleaning your gasket after each use and treating it with care by never using abrasives and harsh detergents, the sealing ring will seldom last longer than six months. Treat it well, and it could last many years before needing replacement.
Set The Right Vent Position
With an open vent, your Instant Pot will never reach full pressure, and you’ll hear the loud sound of steam being pushed out from the moment the pot starts getting hot. The only time that your vent needs to be open is when you are depressurizing your Instant Pot, never during cooking. When in operation, the valve of an Instant Pot Duo should be turned clockwise into the ‘Sealing’ position, while on the Instant Pot Ultra and other models, there is no togglable feature but a pressure release button instead, which means that the vent is set correctly at all times.
Turn Down The Heat
When a meal with a particular viscosity or level of fullness in the pot is cooked at too high of a heat, your Instant Pot will constantly be releasing the excess steam to balance the pressure. Notice how long it takes for the venting hissing to start at full pressure. If the hissing starts too quickly and repeats in quick intervals, your temperature is most likely too high.
Verify Moisture Level
Too low of a moisture level can be detected by Instant Pot venting pressure far too frequently. What is happening is your pot doesn’t have enough liquid in it to maintain pressure, so it needs to keep heating up in an attempt to get the pressure stable. As it over-pressurizes, the excess steam is immediately vented hence the repeated hissing. In this case, add a little water or stock to balance the pot. After all, you don’t want your food to cook dry in a jiffy, either. Every Instant Pot and pressure cooker needs at least half a cup of liquid to pressurize adequately as a general rule of thumb.
Don’t Overfill Your Instant
When there is too much food in an Instant Pot, maximum pressure builds far too quickly, forcing the unit to vent steam and emit that sharp hissing sound frequently. Adhere to the maximum fill limits, and your food will come out better without a worrying hiss off and on in the background.
Try Shrinking The Stretched Sealing Ring
For a temporary fix, give the following steps a try to shrink a stretching sealing ring:
- Clean your Instant Pot’s seal and set it aside.
- In a separate pot, bring enough water to submerge the ring comfortably to around 220-240°F, which is attained by sustaining a rolling boil for 2 minutes (the optimal temperature for silicone).
- Drop the seal into the bubbling water, turn the heat off, and allow it to stand in the pot for 5 minutes.
- Prepare a dish with enough ice water to submerge the sealing ring (the colder, the better, add ice if possible)
- Carefully remove the seal and plunge it into the icy water.
- After 30 seconds, remove, dry, and place in the freezer for 30 minutes.
With a little bit of luck, your stretched seal will be far closer to its original dimensions. Try fitting it into your Instant Pot securely. If this works, you’ll have another few sessions before needing to procure that replacement.
Okay, So What If It Won’t Stop Hissing?
If you’ve replaced the gasket, checked the valve, vent, and liquid level, and lowered the heat, but your instant pot continues to emit a hissing sound, then the inner pot itself is most likely warped, or the pressure sensor is faulty. Warping will only occur after extensive use, which also probably means that the Instant Pot in question is well outside of its warranty period. The only way forward at this point is to treat yourself to a newer, better appliance. However, a faulty sensor causing hissing throughout the pressurized cooking phase can happen with a brand-new unit, in which case you’ll be eligible for a free replacement.
Instant Pot Hissing – Frequently Asked Questions
If we haven’t answered all your questions about fixing a hissing Instant Pot, these answers should resolve any lingering concerns.
It is perfectly normal to have a small amount of steam escaping the safety valve of your Instant Pot. The only time that steam leaking from the release valve should pose a cause for concern is if your pot never reaches full pressurization, thus triggering the lifting of the float valve. Steam is safely emitted from the steam release handle, which doubles as the valve on most Instant Pots, while steam should only be emitted from the steam release valve on the Instant Pot Ultra series. Any hissing through the sides of the pot, and it’s the seal that needs replacing.
Although every Instant Pot comes with a one-year warranty, most users report durability of up to three to five years on average. The inner seal lasts anything between six months to two years, depending on how well it’s been maintained.
Instant Pot supplies spares for all of its units. Not only can one buy a new seal, inner pot, float valve, power cord, condensation cup, and a full range of accessories, but even a completely new base is available for each and every model. Simply note the serial number and model from the back of your cooker and contact Instant Pot support online. You can also find replacement sealing rings and other Instant Pot parts on Amazon.com
While manual pressure cookers still leave room for human error, as one can clearly see here, Instant Pots come with built-in safety mechanisms that prevent them from overpressurizing and exploding. Firstly, the lid of every Instant Pot locks securely once under pressure which prevents it from exploding. If it doesn’t lock, excess pressure, which would otherwise reach dangerous levels, is constantly vented out. There are also up to three built-in safety valves that automatically lift, creating an outlet for excess steam, thus releasing dangerous pressure before danger levels are reached.
Blockage of the vents is prevented by means of an anti-blocking vent placed strategically. Each unit automatically detects the internal pressure, temperature, and position of the lid. Your Instant Pot will switch off by itself before hazardous pressure levels are reached. Instant Pot’s final failsafe is a mechanism that flushes extreme pressure into the internal chamber if a dangerous situation arises. Furthermore, electrical faults are covered by an automatic fuse that cuts power in the case of a fault.