Masterbuilt 40-inch Digital Charcoal Smoker Review

Masterbuilt continues its quest to marry technology, convenience, and affordability without sacrificing authentic charcoal and wood flavor. The 40-inch Digital Charcoal Smoker is a vertical cabinet-style smoker that blends the ease of thermostatic control with the smoky flavor you expect from cooking with charcoal and wood chunks. You can connect this cooker to your smart device via Wi-Fi for remote monitoring and control or ignore that technology altogether and simply be content knowing it’s there. Either way, you get a relatively trouble-free experience with the authentic flavor of much more hands-on cookers. I love the familiarity and capacity of a cabinet style smoker with the added bonus of electronic temp assistance.

Masterbuilt’s 40-inch Digital Charcoal Smoker features a top cook chamber with a windowed, adjustable latch-secured door. There is no insulation strip on the door. Inside is the included water pan, which holds up to one half gallon of water, and four slide out cooking grates that can be arranged in eight height positions. 

The bottom door also latches shut and is sealed with an insulation strip. Open it to access the charcoal basket and ash bin, as shown in the picture. A thermostatically controlled fan stokes the fire. Add your favorite lump or briquet charcoal to the charcoal basket, light the charcoal with your choice of starter, then set the desired cooking temp on the digital control screen and close the doors after the charcoal is lit. Masterbuilt does the rest for you. 

A variable speed fan immediately feeds the coals oxygen until the set temp is reached in the cooking chamber, then the fan slows to a quiet crawl or stops completely until the temp drops and it needs to stoke the fire again. As with a pellet smoker, this process repeats as needed to maintain the set temp throughout your cook, circulating hot smoky air around your food while you enjoy other activities. Yes, it’s that simple. No babying the coals or adjusting vents to maintain temperature.

Startup

Electricity is required to use this device. Start by connecting the supplied power adapter to the cooker then plugging it into your power outlet. The fifteen foot cord is plenty long, which is great since Masterbuilt recommends you leave ten feet of space on all sides during use. The power cord is more heavy duty than the one on Masterbuilt’s thermostatically controlled  Gravity Series grill/smoker I reviewed a couple years ago and should last much longer for repeated use in weather extremes. However, Masterbuilt still recommends removing this cord after each cook and not leaving it out in the weather.

To season the unit before cooking, follow the startup procedure in the manual to fire up the charcoal. Seasoning this unit takes three to four hours, and Masterbuilt recommends doing the seasoning procedure twice with a complete cool down in between before cooking. The first seasoning run removes manufacturing chemicals and oils. For the second seasoning run, you wipe the charcoal basket and ash tray assembly with vegetable shortening or oil then repeat the three to four hour procedure. No mention is made in the manual about oiling the inside of the cook chamber or the grates, but you might as well while you’re at it. Needless to say, seasoning per their directions will eat up an entire day, or a good chunk of two days. Plan accordingly. After seasoning is complete, regular startup is easy, and I was ready to cook in minutes as advertised.

Note: there are three different lighting procedures for desired temp ranges: one for 225°F, a second for the 230-270°F range, and a third for 275°F and above. These simple procedures are clearly spelled out in the printed and online manuals and need to be followed for best and quickest results (and the least amount of hair-pulling).

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The charcoal basket assembly is made up of three parts:

• The ash bin, in which everything sits and which collects the ash.
• The charcoal basket, which holds the fuel.
• The removable charcoal partition, used to form a “snake” or “fuse” to extend the burn time during low and slow 225-270°F cooks. (Click here to learn about the “snake method” and other smoker charcoal and wood setups.)

 Wisley, Masterbuilt built spacers into the ash bin to raise the charcoal basket up a bit and allow airflow underneath to avoid snuffing out fire from ash buildup.

Masterbuilt sells their own charcoal starters but any decent ones will work. I prefer the white starter cubes like those made by Weber. Regardless, the manual recommends waiting three minutes after lighting the firestarter(s) before closing the doors and allowing the fan to turn on. I go for five to ten minutes to ensure the coals are well lit and avoid a false start.

Thankfully, if the coals don’t take and the cooker fails to rise in temp, the controller will tell you via a series of beeps and an error message of “Err 4” on the screen, meaning the charcoal failed to light. More error codes and their meanings can be found by searching the FAQ section of Masterbuilt’s website. Masterbuilt does not have a specific page for error codes in their manual. The codes are buried in their FAQ page on their website. They claim the codes are in the manual, but they ain’t in mine. Perhaps they have a new version of the manual?

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Digital control panel

The control panel includes a red power button surrounded by four buttons that toggle the digital display between the cooker set temperature, meat probe temperature, countdown/count-up timer function, and Bluetooth/WiFi pairing. There are four probe jacks on the left side for up to four Masterbuilt meat probes. One is included and more can be purchased. Press the top “probe” button shown in the picture to view the probe(s) temps. 

You adjust the cook temperature anywhere from 225°F to 400°F by pressing the thermometer symbol button on the left then turning the knob on the right. Press the same button again to set that cook temp, or it will set itself automatically after three seconds.

The display defaults to reading the current cook chamber temperature once a temp is set and the fan has turned on. Prior to setting a cook temp, the display defaults to “00:00” for the timer display. It will also read “OPEN” if the cooking chamber door is opened. Opening stops the fan and disconnects remote access, which are both intentional safety features. 

Curiously, opening the bottom charcoal door stops the fan as well, yet does not cause “OPEN” to read on the display. This isn’t a big deal, though. If you can read “OPEN” on the screen then you can also see that the door is open, right? Closing the doors automatically restarts the fan to continue your cook if you are below your set temp.

The control panel is the same as the one on Masterbuilt’s Gravity Series Smokers (read my review of Masterbuilt’s Gravity Series 560 Smoker here), and while it works well, a minor nit to pick is that the glossy screen is hard to read in bright sunlight. (It’s much easier to read in dark or cloudy conditions.) The display is weather resistant, but it should be noted that nothing on this cooker is completely waterproof.

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Temp control

Temperature control where the 40-inch Digital Charcoal Smoker really shines. On most charcoal cookers, you control temperature by lighting charcoal and then adjusting the airflow with intake and exhaust dampers. Oxygen feeds the fire, so air control is critical for temp control. Aftermarket thermostatically-controlled fans can make this process easier and faster, but Masterbuilt simplifies it even more. The built-in fan and thermostatic controller make this a plug and play charcoal smoker. Just set your cooking temp and it’s maintained like an indoor kitchen  oven.

With a temperature range from 225° to 400°F, this smoker is perfect for anything from low and slow ribs and brisket to a hotter cook for poultry and even pies. This range does limit the device to low and medium cooking temps as it simply will not get hot enough to effectively be used as a grill. So, nix those plans of searing steaks or burgers here! 

Masterbuilt claims this smoker reaches 225°F in eight minutes or 400°F in seventeen minutes. Note that this does not mean it will go from 225 to 400°F in nine more minutes, as each of these two temperature ranges requires its own lighting procedure.

Overall my tests agreed with the manufacturer’s claims, although in cooler, windy weather it took over twenty minutes to reach 225°F when following the recommended 225°F lighting procedure. When aiming for 325°F and using the separate lighting procedure for 275°F+, I reached 325°F in ten minutes, and that was with a chilly ambient temp of 35°F but less wind. All of these tests were performed after waiting at least three minutes from lighting the charcoal starters, as Masterbuilt instructs. Clearly, weather plays a factor in startup and preheat timing.

Temp accuracy

I checked the actual temperature variances with four digital thermometer probes placed at various points in the cooking chamber. One probe was placed near the unit’s controller sensor probe. Temperatures from this probe closely matched the control panel readout, often within single digit degrees. The other three areas were all in the center, with probe 1 being at the lowest grate position, probe 2 being in the most central position, and probe 3 being at the highest position. All three probes often varied by five to twenty degrees, with the hottest areas being the lowest grate near the fire below and the top grate. The center grate was more inline with the control panel readout, although rarely did any match it perfectly. WIth all racks loaded you may have to occasionally swap out foods from one rack to another for even cooking, but I feel this is an acceptable and minor variance. 

Overall, my test probes showed that the actual cooking temps in the center at three different levels were on average ten to fifteen degrees higher than the device’s readout, with the center probe reading the closest. When the included water pan was not used, the actual temps were thirty to sixty degrees hotter than the unit’s displayed temperature. Using the water pan, filled with hot water, greatly leveled the temperatures and is therefore very highly recommended. Read more about the advantages of using a water pan here. I found outside weather to be a significant factor in both the accuracy of the cooking temps and the longevity of the charcoal. More on that later.

Charcoal capacity

The manufacturer’s website claims you can fit up to twelve pounds of briquets in the charcoal basket when using the charcoal partition with the “snake method” for smoking temps of 225-270°F, as shown in the picture above. With the charcoal partition removed, the hopper can hold up to sixteen pounds of briquets  or twelve pounds of lump charcoal. Over-filling the charcoal basket makes it difficult to slide into the charcoal chamber.

Masterbuilt states a full basket of sixteen pounds of briquets will achieve a burn time of “up to thirteen hours”, I suspect that means in the best conditions, such as a lower cook temp on a hot summer day. My tests never achieved that length of smoking time. 

With wind and chilly ambient temps averaging in the mid-40s, twelve pounds (weighed) of Kingsford Original briquets set up with the partition in place as instructed for 225°F gave me about 5.5 hours running at a set temp of 225 before the heat dropped and I lost my firepower. Cooking hotter at 325°F, I got about six hours from a full basket with sixteen pounds of Kingsford Original briquets before temps began dropping beneath my setting. Repeated tests in similar weather averaged about the same. It stands to reason that in hotter summer weather you’ll get more burn time, and cooler and windy weather will decrease the burn time of your charcoal. 

Cooking capacity

The vertical orientation makes this a crowd-ready, high-capacity machine! The main cooking chamber includes four movable 22 x 15 inch wire grates, which can be adjusted to any combination of eight height positions. More grates are available from Masterbuilt, so if you decide to expand to eight total grates you’d get about 2,640 square inches of cooking space with just over two inches headroom between each. That’s a lot of room for thinner meats such as salmon or jerky. Keep in mind though that loading it up that full will likely affect the airflow and temp from top to bottom. Total clearance from the lowest grate position to the ceiling is about nineteen inches. Removing some grates will give you plenty of space for two or three packer briskets or two large turkeys. You have a plethora of cooking options!

Using smoking wood

For authentic wood smoke flavor, Masterbuilt recommends two ways to use wood chunks:

1. When smoking at 225-270°F, add chunks inside the charcoal partition, as shown above.
2. Disperse a few chunks among the unlit coals, either mixed in or on top.

 Note: the charcoal partition is not to be used when smoking above 270°F. 

Cook tests

The 40-inch Digital Charcoal Smoker performed well in both 225°F low and slow smoking and hotter 325°F poultry-specific tests. In my first test I cooked Meathead’s Last Meal Ribs.  I followed Masterbuilt’s 225°F lighting instructions, added twelve pounds Kingsford Original briquets to the basket with the partition in place, added about a half gallon of hot water to fill up the water pan, and set the dial to 225°F. 

The temps, according to my digital thermometer probes, ranged from about five degrees below the set temp to fifteen degrees above. If you want medical precision with your temps, you may fret about these variances, but I am plenty fine with this as, in my opinion, small variances in temperature are usually more of a concern to the human than they are to the meat.

The ribs cooked as expected, and my Duroc St. Louis cut ribs were done, according to the bend test, in about five and a half hours. Mmm, they were as delicious as they look! Beautiful mahogany bark, a smoke ring to remind your eyes that wood was involved, and enough wood smoke flavor to convince your tongue as well, without tasting over-smoked by any stretch. I added a dollop of Max Good’s Black Swan Sweet Cognac Gourmet BBQ Sauce to them and had a very happy mouth!

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Like many smokers, the 40-inch Digital Charcoal Smoker cannot be set for 2-zones simultaneously, but that’s OK because it’s not a hot and fast “grill” and it’s not advertised as one. However, its temperature range of 225-400°F provides good versatility for smoking and roasting. 

The next cook was hot and fast spatchcocked chicken with a fun mix of Meathead’s Amazing Poultry and Red Meat rubs. I set it up per the manual’s 275°F+ lighting instructions and, once the coals were lit, set the smoker’s temp to 325°F. That’s a good roasting temperature for crisping poultry skin without overcooking the meat. Cook temps at the various heights were very similar to the low and slow cook, with temps ranging from spot-on to 20 degrees higher.

I placed a Smoke X4 digital thermometer probe into a breast to monitor the meat during the cook. According to the USDA, poultry meat is safe once the meat reaches 165°F internal temperature, whether or not the juices run clear. I took the breast pieces up to about 160°F as measured on my trusty Thermapen MK4 instant read thermometer before pulling it off the smoker, to allow for a little further rise in temp from carryover cooking. Juicy and delicious, and no sauce needed! Afterward I slapped my head and thought, “Why didn’t I use the built-in meat probe!” Force of habit I guess. Masterbuilt’s meat probes work fine.

All of my cooking tests turned out great. I had occasional trouble maintaining temperatures in extreme winds and chilly air, as noted above, but these were easily rectified with small adjustments to the set temp and a little patience. In better weather things were easier, and after about an hour of cooking the internal components and water pan came up to temp and stayed within an average of ten to twenty degrees of the setpoint, as measured throughout different heights in the cook chamber.

There was no fussing with vents required, and following Masterbuilt’s recommendation for using wood chunks, the food tasted on par with what I’ve enjoyed from any of the charcoal cookers on my deck. Whether you’re new to the world of smoking or an experienced backyard pro, my cook tests showed that the 40-inch Digital Charcoal Smoker should meet your expectations for great food, genuine BBQ flavor, and better yet, make you a hero to your friends and family without breaking a sweat or the bank!

Reloading fuel

Adding more charcoal is relatively simple, but not completely carefree. Open the bottom door and remove the charcoal basket/ash bin. This requires high-temp gloves or oven mitts and something safe to set the HOT ash bin on, such as a concrete sidewalk or a paver stone.* You can use tongs or an ash rake to drop the ash down into the ash bin, then add more charcoal, place the whole ash bin/charcoal basket back into the smoker, close the lid and latch it. The fan immediately picks up where it left off. *Masterbuilt cautions that concrete and pavers could explode under rare circumstances when covered with a basket of red hot coal.

Be sure to reload before the lit charcoal runs completely out or you will have to restart the fire from scratch! I found raking the remaining lit coals to one corner and adding fresh coals in contact to them restored temperatures within a few minutes with the fan’s assistance. If you fear you don’t have enough lit coals left, you can always start a small amount of charcoal in a charcoal chimney and add them to the basket when it’s time to reload. As with anything, you will learn more tricks the more you cook.

Shut down

You cannot save unused charcoal from one cook to the next since the unit cannot be sealed airtight, so Masterbuilt recommends turning the temperature dial to its max setting of 400°F when you’re finished cooking and allowing the remaining charcoal to burn out quickly. I ignored this to see what would happen by simply shutting it off, and it just took longer for the coals to burn up and the unit to cool down. There were a few tiny coals left in the charcoal basket the next day, but nothing usable, so I side with Masterbuilt on this one: turn it up and let ‘em burn. For safety, wait until the unit is cool to the touch before covering or storing.

Ash removal

Getting rid of the ash poses some minor challenges, especially if you’re doing so mid-cook. Some ash drops down into the ash pan under the charcoal basket. The rest of it needs your assistance with tongs or an ash rake, you can dump it by hand. The ash tray/charcoal basket can be removed and the ash discarded easily enough when cooled off, but if the ash bin is hot you will need high temp grill gloves or oven mitts and something heat-safe to set it on, such as a concrete paver or sidewalk.* 

Cleanup

The 40-inch Digital Charcoal Smoker has a grease tray, which is essentially the divider between the upper cook chamber and the lower charcoal chamber. Grease drips on this and sizzles, adding fabulous flavor. Cleanup is as simple as scraping the burnt gunk off the tray and occasionally removing it for some extra TLC. 

While the grease tray is technically removable, it is a minor pain since it doesn’t simply slide out. You must first remove the water pan and water pan rack, and any lower grates, and then tip it up at an angle in order to clear the sides and pull it out. Masterbuilt recommends this be cleaned before each cook to prevent the chance of a grease fire.

Accessories

Masterbuilt strongly recommends this cooker be covered and stored in a cool, dry place. Thankfully they offer a very nice custom cover, and it’s highly recommended since this electric smoker is not very water-resistant. When I left the smoker out in the rain uncovered, water pooled in the lower door’s bottom lip and collected inside the top door, too. I heard sloshing as I moved the top door open & closed. 

I found that moving the top door quickly in an open-closed-open-closed motion caused water to flow out of the lower corner, so I did this until it stopped. While concerning, this is surely why Masterbuilt recommends the unit not be left out in the rain, especially uncovered, as I rebelliously did. Notably, I did not see any water inside the smoker, and the electronics seemed to work just fine after rain exposure. If I did this repeatedly, though, I expect the top door would start rusting out pretty quick.

As mentioned above, one meat probe is included and you can purchase three more. If you do not have a high quality digital thermometer, like the four probe Smoke X4 from ThermoWorks that I used in my tests, additional meat probes make it easy to take multiple pieces of meat to the perfect safe-yet-still-juicy doneness levels without guessing. And remember, you can expand the cooking grates from four to a total of eight. Masterbuilt also offers fire starters and lump charcoal.

Wi-Fi app

The manual refers you to Masterbuilt’s website, which details how to connect your smart device to take advantage of the 40-inch Digital Charcoal Smoker’s Bluetooth/Wi-Fi features. Connection requires first downloading the free Masterbuilt Classic app for Android or iOS to your smart device, then enabling your GPS/Location services and Bluetooth on your device. The app itself instructs you on-screen how to add your cooker, then connect it via Bluetooth, and lastly how to connect to your home Wi-Fi network. Regarding Wi-Fi, the cooker will only connect to a 2.4Ghz connection, and will not work with 5Ghz connections. Masterbuilt also has a handy video showing this whole procedure.

As with many other “smart” cookers, the wireless connectivity was hit or miss. Sometimes it would connect but the connection would later fail. Sometimes it took a long time to connect or flat out would not connect. Other times it connected fine and remained connected throughout the cook. Masterbuilt told me that this is a known issue, and they’ve been working on corrections. Future software updates and technological advancements are expected to alleviate this in time. 

Thankfully, the 40-inch Digital Charcoal Smoker doesn’t require these wireless connections to function, so if you don’t have any fancy wireless devices, or don’t care to use them, you can still smoke successfully. You only need a power outlet.

Conveniences

Masterbuilt wisely included a probe port with rubber gasket to run your thermometer probe(s) directly into the cook chamber instead of pinching them in the door. This is located on the left side panel toward the bottom of the cooking chamber door. Four probe wires have no trouble fitting through.

The large window in the cook chamber door allows you to take a peek without opening. The charcoal chamber door has an insulation strip to ensure a good seal. An adjustable, easy to work latch secures each door. Safety switches on both doors sense when either is open and stop the fan. I had problems with  similar safety switches failing on Masterbuilt’s Gravity Series, but the switches on this model worked great.

Four locking casters and two solid side handles facilitate easy movement. The casters lock the cabinet in place nicely.

Drawbacks

The occasional wireless connectivity issues mentioned above may always be part of the experience with “smart” cookers, at least until technology improves across the board, and while it can get frustrating, I’m happy this cooker doesn’t require these connections to function. 

The charcoal basket warped a little after the first cook. The basket itself is thin metal and easy to bend back into shape, but it doesn’t want to hold the correct shape after warping. This is a minor issue and of very little consequence as it does not affect the cooking experience.

While the large window on the top door is a nice feature, it only takes a few long cooks to cloud up with soot and gunk. This is hardly unique to Masterbuilt. All smoker windows go black without regular attention. Thankfully, cleaning isn’t too hard with some warm soapy water or a strong glass cleaner, and some have even reported success using a grill grate cleaner to bust that stubborn window soot. Then use a soft bristle brush, a sponge pad, or a proper glass scraper. So if a window appeals to you and you want to keep peekin’ in, you’ll need to clean the glass regularly.

As noted earlier, foul weather, most notably strong winds, affect this smoker more than I’d hoped, but that would be an issue with a traditional charcoal smoker as well. I did not notice these sort of temp issues in calm weather. Thankfully, raising the set temp in 5°F increments, along with a little patience, helped compensate. There is a fair amount of smoke leakage from around the top door during normal use as you might expect from an unsealed cabinet door.

One final drawback: you cannot easily cool the smoker down during a cook. Unlike charcoal smokers with tight vent control, the 40-inch Digital Charcoal Smoker cannot be sealed off to cut airflow and lower the cook temp. The dial can be turned down and the fan can shut off, sure, but it will still passively burn the coals without much control to back things down. Keep this in mind when you decide on a cook temp!

Build quality

Build quality on this unit is neither ultra heavy-duty nor flimsy, but it’s as solid as could be expected in this very affordable price range. At 49 inches tall x 29 inches wide and 26 inches deep, it’s a bit larger than I expected, which was a great thing. This may not be the cooker you’ll pass on to your grandchildren, or even your children, but you’ll make BBQ that will delight you and yours, and for less coin than many other more complicated options out there. Follow Masterbuilt’s recommended maintenance and cleaning suggestions and be sure to store it in a cool, dry place, and cover it whenever possible, and you’ll get the longest life possible from this smoker.

Packaging and assembly

Everything arrived from the delivery company undamaged and all pieces were packaged very well inside the unit so the box isn’t any bigger than it needs to be, which reduces shipping costs. All hardware, including a thin wrench for the four locking casters, is included. The remaining tools, however, are not included. You will need a Phillips screwdriver, adjustable crescent wrench, and a 19mm socket and ratchet. 

Assembly went smoothly, although there is a lot to do. The manual suggests allowing 45 minutes for assembly, and recommends having two people to reduce time, but I did it by myself with an adult beverage or two and survived, although it was not completed in 45 minutes. I took my time and finished in about 1.5 hours. But hey, it wasn’t a contest. All pre-drilled holes lined up decently, all required washers and bolts were in a handy blister pack, and there were very few head-scratching moments interpreting the manual’s pictures-only instructions.

Many online reviews mention trouble with bent parts, misaligned holes, and other similar problems, but I did not experience any of these issues.

Bottom line

Masterbuilt has long catered to the average backyard griller and pitmaster by making affordable products that work well without breaking the bank. The 40-inch Digital Charcoal Smoker fits that description well. It is a set it and forget it smoker capable of producing great smoked brisket, ribs, chicken, turkey, jerky and salmon. At a current MSRP of $349.99, it offers a lot of convenience and genuine smoke flavor for your dollar. The wireless connectivity issues were irritating, but due to different smartphones, operating systems, and Wi-Fi modems, this is very common with “smart” outdoor cookers and not unique to Masterbuilt. And besides, as noted above, wireless connectivity isn’t required for use.

We deliberated, and, all factors considered, we feel the conveniences packed into this device and the hands-off ease with which a barbecue novice can get stellar results at a very affordable price point, balanced against some very minor quibbles, earns the Masterbuilt 40-inch Digital Charcoal Smoker our Gold Medal. 

Warranty

All Masterbuilt grills and smokers come with a one year warranty from date of original purchase with proof of purchase, excluding paint finish and rust.

We thank Masterbuilt for providing a unit for our tests.