That weird hissing sound that comes out of your instant pot can be scary. We’ve all been there before, but when you understand why it’s hissing, you would know how to handle the situation better. So, why would an instant pot hiss?
An instant pot would hiss when its internal pressure becomes too high, and the safety valves open up to release the excess pressure. This release from the pot is what creates a hissing sound as the pressure leaves the instant pot. Instant pots usually make less noise than other pressure cookers.
Check out this guide for everything you need to know about the hissing noise in instant pots.
Is My Instant Pot Supposed To Hiss?
Hissing is a normal and expected feature in all pressure cookers, including instant pots. The lid of your instant pot is designed to release the excess steam inside to acceptable levels so the food can cook properly.
When the pressure builds up, the safety valves open to allow excess pressure to come out, which is sometimes aided by the cooker lid’s rattling. As long as you are using it for cooking something, then it’s supposed to hiss.
Is It Safe If My Instant Pot Is Hissing?
Yes, it’s completely safe if your instant pot is hissing. However, if the hissing sound continues for a long time, there might be a problem. It may be that the instant pot was not seated properly or something is damaged. You should get the written guide that came with the pot and start troubleshooting immediately to detect the problem.
Ideally, electric pressure cookers such as instant pots shouldn’t hiss or rattle for long periods. Even when it hisses, it’s supposed to be very quiet and almost unnoticeable. It has computer chips that keep the temperature and pressure at acceptable levels for the food.
After you’ve finished cooking, the instant pot should hiss a little as it’s set to let out the pressure at a rapid pace.
Why Is My Instant Pot Hissing?
The hissing sound made by an instant pot is similar to that made with a tea kettle. In the instance of a tea kettle, it hisses when the steam gets hot enough to carry the lid on the kettle, making it whistle. This is a quick way to know when the boiling water in a kettle is ready.
It follows the same basic principle as an instant pot, but a hissing sound doesn’t mean the food inside the pot is ready.
Pressure cookers generally use a form of liquid like stock, broth, wine, or most generally water to trap the vapour that comes from the liquid in steam form.
This way, it traps all the steam inside the pot to generate heat which cooks up the food faster than other methods. This method also regulates and reduces the time needed for your food to cook.
There is a seal between your lid and the undermost part of the instant pot that effectively shuts the system out. An increase in vapour in the system will cause a corresponding and rapid increase in the liquid’s temperature and pressure.
This high pressure and temperature infuse the food with steam making it cook at a very fast rate.
If your pressure cooker uses water, this temperature can go well above the water’s normal boiling point, about 212oF. Pressure cookers can make this temperature spike as high as over 250oF. This is why the pressure cooker has to release the pressure sometimes while cooking, so it doesn’t become too much for the food.
All instant pots and pressure cookers have a vent on their lids for releasing this excess steam. When the system detects that the cooker’s pressure is extreme, this lid opens to allow the excess pressure to escape. The fast release of pressure as steam through the valve causes the hissing sound heard in pressure cookers.
Instant pots and other pressure cookers are especially good for foods that take a long time to cook as they can handle the high pressure and temperatures. Foods such as tough meat will absorb moisture quickly with a pressure cooker tenderizing it in no time.
Softer foods such as vegetables will get caramelized quickly on a pressure cooker because of the intense heat.
Why Is My Instant Pot Releasing Pressure While Cooking?
An Instant Pot can lose pressure while cooking and cause a hissing noise due to several factors. If your Instant Pot continues to hiss while cooking and after the warm-up period this indicates something is wrong with the appliance.
The most common reason this would be happening is if the valve was not set on seal and is still on vent, this would cause any of the steam to keep being released and not be filling the pressure cooker with steam as it should.
Alternatively you may find that the valve is broken on requires replacing. You may also notice the hissing happens if the seal of the lid needs replacing.
What Causes My Instant Pot to Hiss?
If the hissing gets out of hand or is abnormal, here are the possible reasons why your instant pot may be hissing.
Instant Pot Not Properly Sealed
Sometimes, this can be a simple mistake when you forget to seal off the pressure valve or seal it partly before cooking. Even when you made sure that you sealed it properly, it might have opened accidentally.
Typical signs apart from the hissing sound are the instant pot takes a very long time to reach high pressures. Since a large portion of all the generated steam is getting released through the open valve, your food won’t also cook fast.
High Pressure in the Cooker
High pressure in the cooker can make your instant pot hiss, as explained above. The hissing sound is an alarm to the owner, indicating that a pressure reduction is necessary. This could happen when your instant pot is sealed well, and the valve was closed when you started cooking.
When you first turn your instant pot on to pressure cook it will build up the steam within the appliance to cook the food. This is essentially taking the fluid inside and boiling it to create the steam, the steam then builds up into the pressure cooker.
Hissing can occur when this process is going and usually lasts 5 – 10 minutes while the fluid inside is reaching boiling point and then after it has reached a peak heat and steam level it will stop.
Insufficient Liquid in Instant Pot
Generally, instant pots need a minimum of a cup of water to perform optimally and pressurize. Your instant pot might also start hissing in cases like this, and your food will not get prepared properly or fast. Also, this depends on your recipes as some will be just fine with ½ cup.
Liquid foods like tomato sauce are very dense and will need you to thin it out with water or broth before cooking it to get the best results.
The Sealing Ring or Gasket is not Seated properly.
A wrongly placed sealing ring creates space for the cooker’s steam to escape out and make cooking slower. If you cannot turn the ring around the sealing rack on your instant pot, it’s not set properly.
This can make steam leak from the sides of your lid and make the hissing sound. You can easily identify this by checking the edges carefully to see if the sealing ring is in place.
How To Stop An Instant Pot From Hissing
Here are the steps you can take to stop the hissing in your instant pot.
Checking Properly Before Cooking
It’s important to have a procedure anytime you want to cook with your instant pot. Check the valves and make sure it’s sealed properly.
Also, inspect the lid properly and ensure there is no problem between it and the lower part of your instant pot.
Reduce the Temperature
This process is just as easy as turning down the heat on stove-top heaters, and the pressure cooker will stabilize. However, on electric cookers, like pressure cookers, it takes some time to reduce the temperature and the elements to cool.
If you have observed that your instant pot hisses more often than usual, you should use two heating elements anytime you cook. One of the heating elements will help generate pressure in the cooker, and the second one will help reduce the temperature.
Add More Liquid to Your Instant Pot.
Some dishes and recipes would need more liquid than normal in your instant pot. Consider adding more brothy or water to the instant pot, so it performs optimally.
If your result after cooking is a dish that is too liquid or thin, a great solution is to use the Saute function so that the liquid will reduce and the food thickens. Alternatively, you can use items that act as thickeners, such as flour, potato flakes, and cornstarch.
Fit the Sealing Ring in Position
If you notice the sealing ring is not appropriately placed, and steam is escaping from the corners to make a hissing sound, you can adjust it back in place. Open the instant pot and push the sealing ring around the ring rack until it’s seated properly and you cannot see any space.
To confirm, try to turn the ring around the ring rack. If it rotates around the ring rack with the same effort you used to push it, it’s properly in place. If it doesn’t rotate appropriately, try again to set it in position.
Instant pots are generally silent for most of their cooking cycle. As explained above, they will make the hissing sound occasionally, and there is no need to worry about it. It would be best if you were concerned when this continues for long instances or you notice damage to any of the parts.
Follow the guide above to determine the cause of the hissing sound and solve the problem.
If you decide to release the pressure yourself, the best method to do this is with the natural release method instead of the pressure cooker valve. This method should last anywhere from five minutes to thirty minutes at the most. This method will typically be useful for foods that may cause foam like grains, rice, pasta, and even some big meat cuts.