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ATK Reviews

How to Tell When Your Charcoal Is Hot Enough

Using charcoal can be confusing. Here’s how you’ll know when it’s ready to use on your grill.

Published Aug. 25, 2023.

Grilling on charcoal can be intimidating. There’s more of a learning curve with charcoal than with using a gas grill, which is pretty much plug-and-play. 

At the test kitchen, we recommend using a chimney starter. A chimney starter makes it easy to light your charcoal so you can get a nice, even fire. 

But once you’ve lit the chimney starter, how do you know when your charcoal is ready to use? Is there a specific length of time you should wait before using it? What visual signs should you look for?

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Here at the test kitchen, we spent a whole summer burning lots of charcoalbriquettes and lumpso we’ve got a lot of data on it.

Unfortunately, the short answer to the question is: timing varies. The amount of time you need to wait before your charcoal is ready depends on the type and brand of charcoal you’re using, the amount you’re using (a full 6-quart chimney versus a mounded 7-quart chimney), and even the weather. 

We also burn charcoal to different levels before using it. For slightly longer, cooler cooks, we call for all the charcoal to be “partially covered with ash.” For shorter, hotter cooks, we recommend making sure the charcoal is fully ashed over. (For details on what this looks like, keep reading.)

In general, our data suggests that it will take between 20 and 30 minutes for all the charcoal in a full, 6-quart chimney to be completely ashed over and ready to use. Lump charcoal burns a bit faster, so your wait time will be on the quicker side of the range. Briquettes take longer to ash over completely, so expect a wait time closer to 30 minutes.

Because the exact timing can vary a lot depending on the many factors involved, however, we don’t recommend setting a timer to figure out when your charcoal is ready to go.

Instead, it’s best to use visual cues to let your charcoal tell you when it’s primed.

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The image above is how your charcoal should look when it’s partially covered with ash. Some of the charcoal is fully covered with ash, but other pieces are just starting to show a little ash. There are some flames, but they’re relatively small and well-controlled. And the charcoal itself has sunk slightly inside the chimney.

This image above is how your charcoal should look when it’s fully ashed. Every piece is covered in a fine layer of ash, and the charcoal has burned down so it sits lower in the chimney. The flames should be just licking at the top of the chimney, but the coals are as hot as they can possibly be.

And don’t worrywhile you don’t have as much charcoal by volume as you did when you started, the charcoal you have will still provide plenty of time (and heat!) for cooking. Don’t be tempted to hurry ahead and pour out your charcoal before it’s fully ashed, or you’ll regret ityour steak just won’t have the thick, well-browned crust you’ve been dreaming about. 

No matter what charcoal you use, you’re going to have to be a little patient as you wait for your charcoal to burn to the right level. There’s no instant gratification the way there is with a gas grill. But that’s part of the fun of using charcoaland we promise you, the superior flavor you get as a result makes that wait well worth it.

Once your charcoal is lit, you should have anywhere between 45 minutes and 3.5 hours of cooking time for a full chimney’s worth of charcoal.

Exact times will vary, but lump charcoal generally burns for times on the shorter end of the spectrum, whereas briquettes give you longer cooking time. Kingsford Original Briquettes, one of the most popular types, gives you about 2.5 hours of temperatures over 300 degrees Fahrenheit.

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