What’s Inside: In this article, I answer the question about whether or not the Nesco Smart Canner is safe. I dive into a study by the Utah State Extension that has caused people many people concerns about buying and using this canner. I also provide additional information on electric pressure canners that can help you make an informed decision about whether or not to buy one.

Key Takeaways

  • Apart from the logo, the Nesco and Carey canners are the same. Everything in this article that is said about one of the canners applies to the other canner.
  • There are many flaws in the Utah study. They primary issue is that they failed to follow the manufacturer instructions in the study, and therefore, the results of the study can’t be trusted.
  • There are many benefits to using electric pressure canners, and you can use them with confidence.

This post includes affiliate links.

In this article, I delve into whether or not the Nesco Smart Canner (Amazon) is safe to use. I also

Pro Tip: Just as a side note let me say that whatever I say about the Nesco 9.5-qt. Digital Smart Canner also refers to the Carey pressure canner. Some other terms you may be looking for include Carey dpc-9ss, Carey dpc-9ss smart electric pressure cooker and canner, stainless steel, Nesco npc-9, Nesco npc-9 smart pressure canner. Since there are a lot of words used, it can be confusing. Rest assured that the information in this article applies to all of those terms, because they are the same canner.

You may have seen some of my videos demonstrating the use of the Nesco electric pressure canner. For the most part, people have found these videos helpful, but I’ve gotten a few. . . .

How should I put it? Hmmm “interesting” comments. Here’s an example of one of the more dramatic ones.
Nesco smart canner dangers

Obviously, I’m not interested in killing anyone, and while this message was over the top, I’ll give her the benefit of the doubt when it comes to her intentions. Perhaps she thinks that people are actually dying as a result of eating food canned in the Nesco pressure canner. If so, I applaud her for yelling at me.

Here’s another comment I got:

some question whether or not electric pressure canners are safe.

Now obviously, her comment is far more reasoned, and she gave a specific reason for her concerns. The report she mentioned was familiar to me, as I had already read it and came to my own conclusions regarding it.

I’m going to go over the Utah study she mentioned, and share my thoughts on it. I’ll also go over a few other considerations regarding the safety of the Nesco and Carey smart canners, and whether or not you should consider using one yourself.


Before I go further, let me say that I have no ties to the Nesco company, am not compensated in any way by the company, and have no personal interest in whether or not you use this type of canner.

I’ve been super pleased with Nesco products in general, am definitely a big fan of the canner. It’s safe, easy to use, and definitely worth it! Check the current price on Amazon.

The Utah Study Controversy

Now that I have that out of the way, let’s review the Utah state extension study mentioned in the one comment. Just a reminder that while it covers the Carey dpc 9ss Smart Pressure Canner (Amazon), the Carey and Nesco are the same canners.

Flaws in the Study

Let’s look at what I consider to be major flaws in the way the study was conducted. The biggest issue with the study is that they did not follow the manufacturer’s instructions for the different devices they tested.

Instant Pot Duo

The first device they looked at in the study is the Instant Pot Duo 80. What you see here is the control panel for the device.

The Instant Pot Duo is not a canner, and should not be used for canning.

You can see that it has several features, and NONE of them are for canning. There are several Instant Pots out there, and only one of them claims to be safe for canning. This doesn’t happen to be the one, and so the manufacturer of it never intended it to be used for canning. So, when the Utah State Extension conducted their studies on this, they failed to use the device in the way that it’s intended to be used.

You can’t expect to use a device that was not created for canning and expect to have positive results in the test.

Power Pressure Cooker XL

Now let’s look at the next device they tested, the Power Pressure Cooker XL.

The Power Pressure Cooker XL is only suitable for canning in lower altitudes.

As you can see, this device does have a canning feature. HOWEVER, on their website, they have this warning:

So you can see that this device does can, but it should only be used in elevations lower than 2000 feet.

Canning Altitude

Let’s look at the information in the study on altitude.

You can see that the devices were tested at 3 elevations, 7,070, 4,500, and 2,917. Even the lowest elevation in St. George was way higher than the stated limited of the Power Pressure Cooker XL. So again, they failed to follow the manufacturer instructions.

The Carey and Nesco Canners

Okay, now let’s look at the Carey, a 9 qt smart canner & cooker that they tested, which of course also pertains to the Nesco 9.5 digital smart canner (Amazon). Here is what they say about the Carey pressure canner (Amazon):

Altitude is an impact aspect of safe canning.

Good News and Bad News Regarding the Nesco Smart Canner and the Carey Smart Canner

So you can see that there is both good and bad news for the Nesco/Carey. Altitude is the key consideration, and unfortunately at least in this material, they did not indicate whether or not they used the proper valve on the Carey when testing.

Let me explain. When you purchase the Nesco or Carey, it comes with these two valves:

The can safely using the Nesco electric canner, be sure to use the right valve, based on your altitude.

The one on the right, the black one, is for lower elevations, 1000 feet or less. It is 10 lbs of pressure. The one on the left, the green one, is for elevations over 1000 feet and is 15 pounds of pressure.

When you purchase the Nesco or Carey canner, the black one, for lower elevations is what’s on the canner. The box includes the green one, for higher elevations, but you have to remove the black valve and replace it with the green one if you are going to can in a higher elevation.

Did the Testers Follow the Manufacturer’s Instructions?

Now it is possible that when the Utah study was done, the testers followed the manufacturer’s instructions, removed the black valve and replaced it with the green valve. Unfortunately, at least in the documentation that I have regarding the study, they do not specify which valve they used, so we can’t know for certain. The only thing we know for certain is that they did not follow the manufacturer’s instructions with the first two devices, and they didn’t indicate in the study which valve they used on the Carey.

Note: If you canning find the Carey Pressure Canner instruction manual, you can follow the instructions in the Nesco canner manual.

You Have to Use the Right Valve in the Nesco Canner When Canning in High Altitudes

One of the things that I love the most about the Nesco electric canner is that you can use it even in high altitudes. As someone who cans at altitudes above 1,000 feet, this is important to me. Two pressure valves come with the Nesco and Carey canners (both available on Amazon). When canning in high altitudes, be sure to use the green valve. If canning below 1,000 feet in altitude, use the black valve.

If they used the valve that came on the canner, the wrong valve for the elevation, the results that they presented would make sense. Again, I can’t state that they used the wrong valve. I can only state what is included in their report, but I do believe that their overall approach in this study was flawed, since out of the gate, they failed to follow the manufacturer’s for at least two out of three of the devices they tested.

The Reliability of the Nesco Brand

Now I want to talk about the claims that Nesco makes about the canner and whether or not they can be trusted.

carey smart canner not safe

The sentence that I want to focus on here is that people need to know that the Nesco canner “could not safely can like it claims.” I’ve heard this same thing or variations of it from others. The implication seems to be that the company can’t be trusted. A lack of trust in a company could be because they feel the company is at worst evil, or at best, incompetent. This is my speculation by the way, but there aren’t a whole lot of reasons for a reputable company to make claims about a product that aren’t true, particularly when it comes to safety.

Nesco is a brand that has been around for a long time. Here’s a screenshot from their website:

The Nesco canner company has a long history and track record of putting out quality products.

I want to zoom in on a little part of it, and the date, 1931. Nesco has been around for 90 years. You do not stay in business for 90 years if you’re incompetent. You also do not stay in business for 90 years if you put out products that kill people.

We live in an incredibly litigious society, and companies bend over backwards to avoid liabilities. Reputable companies like Nesco are MUCH more likely to not say that something is safe, even if it is, than they are to say that something is safe when it isn’t.

Nesco has far more to lose by putting out a product that isn’t safe, than they could ever gain financially from selling an unsafe product.

Independent Testing of the Nesco Canner

Now let’s talk about testing.

Nesco has done their own testing, but I want to share about some independent testing that has been done to ensure the safety of the Nesco smart canner. The Nesco canner is ETL approved. ETL stands for Electrical Testing Lab. ETL approval is an internationally recognized seal of quality, safety and professional manufacturing. To get the seal of approval, products have to go through rigorous inspections and testing.

The ETL lab takes the product from the company, tests it to make sure it performs as stated. Then, they completely disassemble it. Every component of the product, all the way down to the wires is inspected, and the products are evaluated based on both U.S. and Canadian regulations and safety standards.

If the product passes the tests, then the factory is inspected to make sure that quality controls are in place, so that every single unit that is produced meets the safety standards. To maintain the ETL approved status, there are intense surprise factory inspections 4 times a year. If they fail to pass a surprise inspection, the ETL approval is revoked.

The National Center for Home Food Preservation Guidelines

Now let’s talk about what the National Center for Home Food Preservation has to say about electric canners. Before I discuss what they say, I want to make it clear that their thoughts are based on the fact that they have NOT tested these devices, so it is sheer speculation on their part. Even so, as you’ll see, all of their “what ifs” are more than adequately covered by the Nesco Smart Canner safety standards.

The gist of what they report says is that they don’t recommend using electric canners even if the manufacturer’s directions say that the device can be used for canning.

The important thing to know is that they base their lack of recommendation on what they do NOT know, rather than what they do know. So in other words, they are saying, “We don’t know, and because we don’t know, we don’t recommend it.”

Why the National Center for Home Food Preservation Doesn’t Recommend Electric Canners

electric canner safety - temperature inside of jars

The first concern has to do with the temperatures inside the jars throughout the canning process. Again, they base their concerns on what they don’t know, rather than what they do know.

Position of Jars and Flow of Steam in the Nesco Smart Canner

They go on to say that that the position of the jars and the flow of steam around the jars impacts the temperature in the jars. This is indeed true, and this is why when you put the jars into the canner, you leave some space in between the jars. This is standard practice when using the Nesco canner.

position of jars and flow of steam in canners

The next sentence, is really odd. It says, “For example, there would be expected differences in jars piled together on their sides from those standing upright on the canner base.” Now maybe it’s just me, but I’ve never thought of filling my jars, and then piling them together on their sides when I put them in the canner. Something tells me that this would be a bad idea for ANY canner, including stove top canners. So again, a really odd statement to make since it really has nothing to do with electric canners.

The Importance of Temperature in Pressure Canning

The importance of temperature in pressure canning

So it starts off by saying that the thing that matters is temperature, not pressure. It then says that this is why a proper venting process is so important in pressure canning.

Venting in the Nesco Smart Canner

Now here’s the interesting thing. I cannot speak to whether or not this occurs in other smart canners, but the venting process does happen in the Nesco and Carey smart canners (both on Amazon). The instructions clearly state that you have to wait until there is a steady stream of steam, and then letting the steam vent for 10 minutes before moving on to the next step. What’s even more interesting is that there are safety features in place that make it impossible to skip this step.

Contrast this with a stove top canner where you should also allow the steam to vent for 10 minutes before putting the weight on, but there are no safety features in place prohibit you from skipping this step.

The Impact of Power Surges and Drops in the Nesco Smart Canner Safety

Now let’s look at the third one:

Nesco Smart canner safety

Now notice again they are basing their concern on what they don’t know. Instead of making a statement, they ask a question. “Do power surges or drops with an electric canner cause the temperature to drop too low?” In other words, they don’t know that that occurs, they’re just throwing that out there as a possibility.

Next they ask, “How will you, the user know if that happens with your cooker?”

I’m glad they asked! Again, I cannot speak to other electric canners, but with the Nesco and Carey canners, if there is a power surge or drop, the canner will turn off, and there will be an error message. According to the canner manual, if you get such a message, you need to discard the food. Bottom line is there are safety features in case this type of problem occurs.

This got me to thinking about what happens if you’re using a stove top canner on an electric stove and there’s a power surge or drop. Does that cause the temperature to drop too low? Also, how will you know if that happens while using your stove top canner? Again, there are safety features built in to the Nesco canner that are missing from the stovetop canners.

carey smart canner safety

Now let’s look at the final concern.

electric pressure canner safety - Nesco pressure canner

As you can see, there are three important stages in pressure canning safety:

#1: Heat from the time the canner is coming to pressure

#2: at during the actual process time

#3: heat during the early stages of cooling the canner and jars.

It states that when the processing time finishes and you “turn off the heat,” the food needs to remain at high temperatures for another period of time. They do not state how long of a period of time, but they do state that you shouldn’t speed up the process.

The interesting thing is that the same process is what is recommended in the Nesco canner manual. It takes up to around a half an hour before the canner starts to vent. You let it vent for 10 minutes, and You then process the food. Once the food is finished processing, the canner automatically turns off. The manual specifically states not to do anything to speed up the cooling process, and to wait for the pressure to drop naturally. The manual also states to wait at least an hour.

In my experience I’ve found that it takes between 60 and 90 minutes for the pressure to drop naturally, which is also similar to how long it takes on my Presto 16 quart stovetop canner.

You can also see that the guidelines recommend only using canners that hold 4 or more quart sized jars. As you can see, the Nesco canner holds 4 quart jars.

Are Electric Pressure Canners Safe?

I love my Nesco canner because it is both easy to use, and safe. I can with greater confidence since I started using my Nesco, and can’t imagine canning any other way! I put my stovetop canner in the shed, “just in case,” but have had no reason to use it since buying my Nesco canner.

In addition to the question of whether or not the Nesco Pressure Canner is safe, I also want to answer the bigger question, and that is whether or not electric pressure canners are safe.

The bottom line is that electric pressure canners are safe, as long as you use them according to the manufacturer instructions. Here are a few safety recommendations to keep in mind when it comes to using electric pressure canners:

  • Be sure you are using electric canners that are indeed canners – and not just electric pressure cookers.
  • Follow the manufacturer instructions. For instance, with the Nesco and Carey Canners, there are two valves provided. To can safely, use the right valve for your elevation. (Use the black valve if your elevation is less than 1,000 feet, and use the green valve if your elevation is 1,000 feet or higher.
  • Only use your canner in the way the canner is intended to be used. As an example, some people use the Nesco canner for steam canning, but while it has a steam option, it is not a steam canner, so don’t use it for steam canning.
  • Follow other safe canning practices, such as using approved recipes from companies and organizations such as the National Center for Home Food Preservation, and the Ball company.

As for me, I’ll continue using this canner and continue making videos showing the use of this canner, because based on my research, in my opinion, it is safe.

Additional Information About Electric Pressure Canners

Since you landed on this article, I can safely assume you are interested in canning in an electric canner such as the Nesco, Carey, Instant Pot Max, or the Presto Pressure Canner. Because of that, I wanted to give you just a bit more information about canning with electric pressure canners, to help you make the best decision.

Are Electric Canners Worth It?

The first thing I want to address is whether or not electric canners are worth it. The thing is, in at least some cases, electric canners are more expensive than stovetop canners. There are exceptions, of course, but for the most part, an electric canner costs more than a pot on the stove. One top of that, electric canners can smaller amounts of food than most stovetop pressure canners.

The Benefits of Electric Pressure Canners

When you consider that electric canners cost more, and yet can fewer jars at a time than stovetop canners, it’s important to consider the benefits of electric canners to know whether or not they’re worth it. Here are my favorite benefits of electric pressure canners.

  • They take the guess work out of canning. With digital canners, you no longer have to worry about whether or not you have the right amount of pressure or if the heat is too low or too high. The canner takes care of those issues for you.
  • You don’t have to babysit them like you do stovetop canners. While it’s still important to stay nearby, you don’t have to watch digital canners like a hawk like you do stovetop canners. For instance, I’ll take a quick shower or watch TV in the other room while canning with the Nesco, and I’d be much less likely to do that with my stovetop canner.
  • They keep track of time for you. I love that there is a countdown timer on electric canners, so at a glance, you always know how much time is remaining. No need to set a separate timer when canning with a smart canner.
  • You can use electric pressure canners anywhere you have an electrical outlet. This flexibility is a great option for those with glass top stoves as well as those who want to be able to can anywhere. I often use my canner on my dining room table so it’s out of the way from what’s going on in the kitchen.

There are many benefits to using electric canners compared to stovetop canners. While many people use both stovetop canners and electric canners, I love my Nesco canner so much, it’s the only canner I use.

The Best Electric Pressure Canners

With so many electric canners out there, sometimes it can be hard to choose the one that’s best for you. Here are my top 3 recommendations for electric pressure canners.

Here are the 3 electric canners that I personally use and recommend. All are available on Amazon:

  • The Nesco and Carey Electric Canners. Since these are essentially the same canner, I recommend buying whichever one is available at the best price.
  • Instant Pot Max. The Instant Pot Max has a smaller capacity than the Nesco canner, but it’s a great option for those who want to use an Instant Pot that can also can. If you only want to do small batch canning (pints and smaller only), and don’t want to have multiple devices, this is the electric canner I recommend.

Water Bath Canning in Electric Canners

While this post has focused on pressure canning, it’s important to know that the Nesco canner can also water bath can. This is true of most if not all electric canners. If you want to purchase just one canner, then an electric canner is a great option.

Related Articles

If you enjoyed this article, you may also enjoy these related articles:


  1. Thank you for this thorough and common sense analysis. Fear mongering seems to be a way of life today. I just purchased my Nesco electric pressure canner and then saw an article that said that it wasn’t safe to use. I started researching and found your analysis. It reminds me of the articles that say I can’t reuse jars from store bought food (in a water bath canner and with some precautions) and I found where many do reuse these jars. I have had great results canning with these jars and haven’t had to spend a bunch of money on brand new “canning” jars. I am looking forward to pressure canning some soups and other low acid foods in my new Nesco canner. Thank you again.

    1. Hi Marcy,

      Thanks so much for your kind comment! I’m glad you found it helpful. I decided to cover this topic because I saw comments from people who had actually bought the canner, but were afraid to use it. That was such a shame, I wanted to present the other side of this. I wish you the best with your canning adventures!

  2. I read your article and agree, however I can’t get my pressure valve aligned correctly and am not able to use my brand new canner , nothing I received in the box shows me how to align it properly. This is the fourth article I’ve read, I will be well informed if I ever get it right!

    1. Cheryl, thanks for your comment. I appreciate your concerns. First, let me make sure that I’m properly understanding your concerns. I’m making a big assumption – that you’re perhaps expecting the valve to “lock” (or click) into a position, and because it doesn’t, you are unsure if you have it aligned correctly. Note that it doesn’t click into place. Just move the valve so that the dot above either exhaust or airtight (whichever you are trying to do) is aligned with the arrow that points toward the valve. When it is in the airtight position the valve sits lower, compared to when it is in the exhaust position. Play with it a bit and you’ll see when it’s airtight, it’s lower, and when it’s exhaust, it’s higher. That’s normal.

      Note that if you are water bath canning, you will use exhaust the whole time. When pressure canning, start off with it in the exhaust position, but you will move it to the airtight postion. (I can give you more specific instructions regarding when to move it to the airtight position, but I think the manual does a good job of telling you when to do this when pressure canning.)

      One other thing to be aware of is when pressure canning, steam will continue to escape even AFTER you move it to airtight. This is nothing to worry about. The steam escaping is to regulate the amount of pressure so it is always the right amount of pressure.

      I hope this helps, but please do ask any additional questions.


  3. Someone sent me a copy of a section of an article that said that USDA did not endorse using their recommended processing times on electric canners. I use the Ball book an canning and preserving and go by their processing times. Is this ok?

    1. Glenda, that’s a great question. Unfortunately, there is a lot of misinformation out there about this canner. It is possible that the USDA doesn’t endorse using their recommended processing times because they haven’t tested it, and therefore can’t recommend it. All of the information that I’ve seen on this is to use the same processing type (e.g. water bath or pressure canning) and times when using this canner, as you would when using a stovetop canner. The only thing you need to adjust is for altitude, but that is true for all canners. Please feel free to ask if you have additional questions and I’ll do my best to answer.


  4. Thank you. I am using the black gauge that is for low altitudes as I am in Mississippi. Everything else I am doing as per the Ball book. I enjoy using the canned, I just hate that these issues and doubts cause me to be afraid to use the food I have canned as the last thing I want to do is harm anyone with the food I can.

    1. It sounds like you are doing everything right! You should check out the YouTube channel, RoseRed Homestead. She uses the Nesco canner. She is very scientific in the way she approaches food preservation, including canning. She has at least one video of her testing out the Nesco, and it passed with flying colors.

  5. Thanks for all the info!
    I just received my new Nesco Digital Canner and am reading the instruction manual. I am confused about the sentence on page 7 that reads:
    “You can LOW PRESSURE CAN most vegetables, fruits, sauces, and soup stocks.”
    So I am wondering when you would use LOW vs HIGH. Would it really be safe to use LOW for canning?

    1. Hi Vicki, thanks for your comment. I just looked at page 7 on my manual, and it doesn’t say that, so it must be a different version. Honestly, that sounds really weird. LOW is an alternate way to can high acid foods instead of water bath canning. It’s good to use when you want to use a water bath recipe in quarts, that are too tall for water bath canning. In that case, use low instead of water bath. BUT, that is only for high acid foods. From what I understand, the low setting is just 6 pounds of pressure, which isn’t enough for low acid foods. I would personally use the high setting for any low acid foods. Basically, if a recipe calls for pressure canning, use high. If it calls for water bath canning you can use low or the water bath setting. I have no idea why the books says what it does.

Leave a Reply

Your email address will not be published. Required fields are marked *