Exploding Pressure Cooker FAQ

Pressure cookers have been around for decades, but they’ve recently become even more popular on the market. The main reason is that they help families cook wholesome, tasty meals in short periods.

The dangers associated with pressure cookers, however, have not disappeared. Even though newer models are manufactured with numerous safety features, some users have still been seriously burned when using them. Many have filed lawsuits against the manufacturers to hold them liable for their injuries.

If you have a pressure cooker or you’re thinking about getting one, it’s best to inform yourself about the possible dangers. Here, we answer some of the most common questions people ask about these appliances.

Table of Contents

Can I Use a Pressure Cooker Without a Whistle?

To use a pressure cooker without a whistle, follow the directions carefully. Always inspect the cooker before cooking to be sure all the seals are in good shape. Then do everything you can to be sure the pressure has all been released before you open the pot.

Many models of pressure cookers are made to whistle as they vent steam and pressure. Others do not. The difference is:

  • With a whistle: The whistle usually comes out of a spring-loaded pressure vent, sort of like what’s on a teapot. When the pressure inside the cooker gets higher than it should, it pushes against that vent. As steam is released through the opening in the vent, it creates vibrations that make a whistling noise. The sound alerts the user to turn down the heat.
  • Without a whistle: Cookers that do not have a whistle have a spring-loaded vent instead, which allows steam to escape without making any sound, or perhaps making only a hissing sound. These cookers release steam to maintain a safe pressure level at all times.

In general, non-whistling cookers are quieter than those that whistle and are designed to better regulate pressure. Many people prefer not to have the whistle going off, so these quieter models are very popular.

What Happens If You Don’t Put a Whistle on a Cooker?

Many of today’s modern pressure cookers do not have whistles. Instead, they are designed to regularly release steam as needed throughout the cooking process.

Can You Leave Food in a Pressure Cooker Overnight?

It’s not a good idea to leave food in a pressure cooker overnight. In theory, they are designed to work unattended. Some may even advertise that you can throw in the ingredients and forget about it, implying that you can walk away and let the cooker do its thing.

Yet doing so can be unsafe in certain situations. If the cooker malfunctions, for instance, it may build up too much pressure and even explode, injuring anyone who is standing nearby. It’s better to keep an eye on it and make sure that it’s operating properly.

It can also be detrimental to leave your food in a pressure cooker  overnight. Here are some reasons why:

  • Loss of pressure: If the pressure cooker automatically turns off at the end of the cooking cycle, the pressure will reduce and the pot will no longer be hermetically sealed or airtight. Air from the environment may be able to get into the cooker.
  • Microorganisms: As long as the food is warm enough, it will kill any microorganisms that the air may introduce. But if you leave it overnight and it cools down, the microbes are allowed to multiply, which may make your food unsafe.
  • Leaching pressure cooker material: If your pressure cooker is made with aluminum, unless it’s anodized, it’s best not to leave food inside it for long periods. The aluminum may leach into the food and can be toxic if ingested.
  • Seal problems: The makers of some pressure cookers recommend that you not leave the pot unattended during the preheat cycle if you cook oatmeal or porridge or other sticky foods. These can develop a foam that blocks the float valve. This, in turn, could affect the sealing process and cause overflow.
  • Food texture problems: Some foods, like rice and pasta, will get softer the longer they are left in the cooker, which can ruin the texture of the meals you’re making.

Most recipes only take an hour or two to cook in a pressure cooker. It’s best to stay nearby through that process to make sure there are no issues. 

Is It Safe to Leave a Pressure Cooker Unattended?

It is best to always be nearby while you’re using your pressure cooker. Though modern electric versions don’t require as much attention as stove-top versions, it’s still best to remain at home until the cooking is done. Unexpected accidents or problems can be prevented if you’re around to watch for warning signs.

Do Instant Pots Turn Themselves Off?

Most modern pressure cookers have automatic shutdown functions. As long as these work correctly, they will turn the cooker off when the cooking process is done. You do need to read the instructions to be sure you’ve activated the cooking process correctly. On many Instant Pots, for instance, you may need to activate the timer so that when it is done, the pot will shut off.

Most pressure cookers also have safety mechanisms that will turn the cookers off if they start overheating or if another malfunction is detected. Read the owner’s manual to determine the automatic shut-down mechanisms included with your cooker.

How Do I Know If My Pressure Cooker is Broken?

Several signs may indicate that your pressure cooker is malfunctioning:

No Pressure

If your pressure cooker is not building up enough pressure, it could be that you have a damaged or faulty gasket. Check that and your pressure valves for any visible damage. If you see any, stop using the cooker and replace the damaged part immediately.

Keep in mind that many gaskets wear out after a couple of years. Regularly inspect yours for damage and replace them when needed.

Another reason the cooker may not be building up pressure is that you don’t have enough water inside. The cooker needs water to build up steam and create pressure, so follow the instructions carefully.

Often, if the cooker is failing to build up enough pressure, it’s because of leaks. See below.


If you are noticing leaks from the lid when the pressure cooker is closed, it could be because of a faulty or damaged gasket or seal. Clean both the lid and the gasket, as dirt and food buildup can cause it to malfunction and cause a leak.

It could also be that the gasket is not fixed properly. Check to make sure it is and that your lid is placed correctly.

Another potential problem is that the rims under the pressure cooker and the lid may be damaged due to wear and tear. Aluminum cookers particularly may have damaged rims or lids.

Finally, make sure that you are properly cleaning your pressure cooker. This can lengthen its life and reduce the risk of these types of problems.

Food Takes Longer to Cook

If your recipes are no longer cooking within the time they’re supposed to, check the following:

  • The level of food or water. Make sure you haven’t overfilled the cooker.
  • There is a thick liquid in the mix. It can delay cooking.
  • There are frozen foods in the mix. They can make cooking take longer.
  • The pressure is not building up correctly. (See above for solutions.)
  • The lid isn’t secured tightly. Make sure the lid is properly locked down.

The Lid Won’t Come Off

Sometimes the lid may not come off as it should when the cooking is completed. This may occur due to excessive buildup of pressure, which may jam the lid. Allow some time for pressure to be released.

Sometimes, even after releasing the pressure, the lid may remain stuck. Again, this probably means that some pressure remains inside the cooker. Always allow enough time for the pressure to disburse inside the cooker before attempting to remove the lid.

You can do this only if the cooker is not electric. Water can damage electric sensors. If you have an electric cooker or if the water doesn’t help on a stovetop unit, wait it out. With time, pressure will be reduced and you’ll be able to open the lid as usual.

You can also try opening or removing the pressure valve on the lid. More on that below.

Follow the instructions carefully for this type of issue. Never remove the lid when there is still pressure in the pot. 

Excess Vapors Are Escaping, or Steam is Trapped in the Vent Pipe

Maybe you’ve noticed food particles accumulating inside the vent pipe. Or you’re noticing vapors escaping from the valve of your cooker and you’re concerned. Or the steam that usually escapes is not escaping.

In most cases, it’s normal for vapors to be released as the cooker releases pressure. If you think yours is letting an excess amount of vapors escape, however, or if no vapors are escaping at all, it could signal a problem. Always check the vent pipe and remove any debris.  

How Do You Depressurize a Pressure Cooker?

Always be sure to protect your face, hands, and body when releasing pressure.

Understanding how to release pressure from a pressure cooker is extremely important. The danger of pressure cookers resides in their pressure, as that’s what can cause explosions and injuries.

Incorrectly managing the pressure release can also negatively affect the food you’re cooking.

Most of today’s pressure cookers will cool and depressurize on their own once the cooking is completed. Most also have an alternative method for releasing pressure. These include:

  • Pressure release handle: This is a big knob on the lid used to naturally release pressure from the pot. It may be sent to “sealing” or “venting.”
  • Float valve: This is a round metal part next to the pressure release handle. During cooking, it is level with the lid. When it drops down, that means the pot is no longer pressurized and can be safely opened.
  • Pressure release button: Most newer models of cookers have a pressure relief valve and button. Pressing the button opens the valve and releases steam, reducing pressure.

Other pressure cookers may have different pressure-relieving methods. Always check the instructions.

In general, you have four ways to release pressure from a cooker:

  1. Natural release: Remove the cooker from heat and allow it to sit until the pressure reduces. This occurs automatically in newer cookers that automatically reduce heat at the end of the programmed cooking time.
  2. Quick-release: Use the steam release valve (or button)—such as those listed above—to expel steam.
  3. Cold-water release: For this method, the user carries a stove-top cooker to a sink and turns on the tap to drizzle cold water onto the lid without wetting the pressure or safety valves. This was often recommended in the past for those cookers that didn’t have a way to alert the cook to pressure remaining in the pot.
  4. Base-immersion release: For this method, the user carries a stove-top cooker to a sink that is partially filled with cool water, then lowers the base of the cooker into that water to partially submerge it. Again, this method may be used with stove-top cookers when other pressure-releasing methods are not working as expected. Be aware that this sort of method, when used with aluminum cookers, may warp the metals.

How Do You Stop a Pressure Cooker from Exploding?

Sometimes the safety mechanisms on pressure cookers do not work as they’re supposed to, which can lead to an explosion. To decrease the odds of that happening, follow these tips:

  • Check: Always check your pressure cooker over carefully before each use. Make sure the seals and gaskets are in good shape. The gasket between the pot and the lid is critical, so make sure it’s clean and not cracked or dried out. It’s also best to replace it once every year or two, depending on how often you use the cooker.
  • Don’t overfill it: Follow the directions carefully when it comes to filling your cooker. If you overfill it, the food may block the vents in the lid, or the pressure may swell to high levels.
  • Release pressure safely: Refer to the question above to make sure you release pressure safely and carefully.
  • Use caution when opening the lid: Never open the lid before the pressure has completely released. Wait the appropriate time after cooking has finished. If you notice resistance in the lid, that means there is still pressure in there. Don’t force it. Use one of the methods above to safely release pressure.
  • Clean the cooker properly: Proper cleaning helps you avoid blocked or dirty vents, gaskets, and valves that may cause the cooker to malfunction. Remove the gasket and clean it separately, then clean out the release valve with a toothpick. Remove the float valve as well and wash it with soap and water.
  • Keep the type of food in mind: Some foods expand more than others and can cause the cooker to fill up more than you expect. Examples include rice, cornmeal, beans, and lentils. The safest approach is to avoid cooking these foods in a pressure cooker.
  • Read the manual: Before using your cooker, make sure to read the instruction manual carefully. Each one is different and what works with one may be unwise with another. Reading the manual also helps you get the most out of your cooker.
  • Keep children and pets away: Burns can be particularly devastating to young children and pets. Keep them out of the kitchen when you’re using a pressure cooker. Teach your children to never bother your pressure cooker for any reason.

How Does a Pressure Cooker Burst?

Most of the time, a pressure cooker bursts if safety mechanisms don’t work as expected, and the lid can be opened before the pressure has been released. Manufacturing and design defects can lead to this sort of explosion, particularly if the lid seals or gaskets are faulty, the cooker fails to adequately vent excess steam, or if the safety mechanisms don’t work properly.

Sometimes, though, the cooker can burst on its own if the pressure builds up too much inside it. This can happen if the food inside—such as rice—creates too much froth, blocks the steam release mechanism, and allows pressure to reach dangerous levels. It’s also possible that if the release or venting valves become blocked for other reasons, the steam and pressure can build up enough to blow the lid right off.

More modern-day pressure cookers that explode often do so because of defective design, cut-rate components, or inadequate product testing. Many plaintiffs have filed lawsuits against pressure cooker makers for these reasons.

How Long Does It Take a Pressure Cooker to Build Up Pressure?

It can take from 5-30 minutes for pressure to build up inside a pressure cooker. The time depends on the type of cooker you’re using and what type of food you’re cooking.

The following factors can affect how long it takes for the pressure to reach the proper level:

  • The size of the cooker
  • The wattage of the cooker (if electric)
  • The heat level (for stovetop cookers)
  • The type of valve
  • The amount of liquid used
  • The amount of food
  • The beginning temperature of the food

How Long Does It Take a Pressure Cooker to Reach 15 PSI?

The maximum operating pressure for American pressure cookers is 15 psi. The European standard is about 13 psi. Any cooker that doesn’t fall within this range is “non-standard.” Most recipes and cooking time charts made for today’s pressure cookers are written to accommodate these standards.

As noted above, it can take from 5-30 minutes for your pressure cooker to reach this level, depending on factors like the size of the cooker and the fill level.

How Much Liquid Should Be in a Pressure Cooker?

The general rule is to always add at least one cup of liquid to your recipe if cooking in a pressure cooker unless the recipe says otherwise. The liquid is what creates the steam that cooks your meal.

If you don’t have enough liquid in your recipe, the cooker will not be able to build up enough pressure. Many of today’s modern cookers will show you a “burn” error if you don’t have enough liquid.

If you have too much liquid, you risk creating excessive pressure and you may also damage the texture of food. As a general rule, never fill the pot more than halfway with liquid.

Always check your owner’s manual to see what amount of liquid your cooker needs to operate correctly. There should also be marks inside the pot that help guide you.

What Happens If There’s Not Enough Water in a Pressure Cooker?

As mentioned above, if you don’t have enough water in your pressure cooker, it will not be able to build up enough pressure to properly cook your food. Your food may burn or fail to cook right.

Is It Normal for a Pressure Cooker to Make Noise?

Yes. As steam escapes from the cooker through the valve, it is normal for it to make some noise, usually some sort of hiss.

Some stove-top cookers may have a whistle that warns when the pressure is building up too high, and you need to turn down the heat. Today’s electric cookers are usually quieter than older stove-top versions, but you will still hear noise when the steam releases.

Is There a Silent Pressure Cooker?

Most of today’s electric pressure cookers are “virtually” silent. These, however, will still make some noise when they vent steam.

Should Steam Come Out of the Float Valve?

While the pressure cooker is building up pressure, it is normal to see steam coming out of the float valve. When the cooker is working correctly, once the float valve seals itself (pops up), there should be very little to no steam leaking out of it. If there is, it could be that the valve needs to be cleaned or replaced.

Why Is My Pressure Cooker Releasing Steam?

In most cases, it is normal for a cooker to release steam, particularly as it’s building up pressure. This helps prevent excessive pressure build-up.

There are some cases, however, where steam may be “leaking” from inappropriate places like around the lid. Other times, there may be more steam released than usual, or the pot may be releasing it at inappropriate times (after pressure has been reached).

If you suspect either of these, check the following:

  • Check the condition of all seals, valves, and gaskets before cooking to make sure they are in good shape.
  • Make sure the pressure valve is set to “sealing.” (If that applies to your cooker.)
  • Check that the sealing ring is evenly seated around the lid. In some cases, you may need to clean or replace it.
  • Place the lid properly.
  • Look for any damage on the lid. If it’s not closing properly, it could allow steam to release from the pot. Check the edges of the pot as well.

Check your owner’s manual for more information on when the cooker is supposed to release steam, and when you may need to clean, reposition, or replace certain items to make sure the pot is operating correctly.

What Can You Not Cook in a Pressure Cooker?

It is smart to avoid cooking some foods in the pressure cooker. Some foods can create froth that may block the steam release valve, creating a dangerous increase in pressure. Others will not cook well under pressure.

For best results, avoid cooking these items in your pressure cooker:

  • Breaded meats
  • Crispy, crunchy foods (fried chicken)
  • Delicate cuts of meat (like steak)
  • Burgers
  • Dairy/creamy sauces
  • Pasta and noodles
  • Rice
  • Potatoes
  • Oatmeal and porridge
  • Yellow and red lentils
  • Seafood
  • Bread
  • Cookies and cakes
  • Thickeners