Home Roasting with the Hearthware Precision

To anyone that owns a Precision Hearthware Coffee Roaster, the thought of writing a tutorial on using it will seem ridiculous. Using the Hearthware is so simple a caveman could figure out the basics. This is a tutorial written for those coffee fans that haven’t started home roasting yet or those already roasting that know little about the Hearthware.

In another INeedCoffee tutorial, we showed you how to roast coffee using a popcorn popper. If using a popper is as easy as making spaghetti, then using the Hearthware Precision is as simple as using a toaster. Are you ready to see how simple it is to make the best coffee of your life from your own home?


Disable Smoke Detector

The most difficult part of indoor roasting is disabling the smoke detector. Roasting coffee will produce smoke. Dark roasts even more so. Since the mission here is not to test your smoke detector and kitchen ventilation, but to roast coffee, you will want to disable the smoke detector prior to roasting.

Add Beans

The machine comes with its own 1/2 cup scoop. Fill up the scoop and pour the beans into the machine.

pouring beans

Start Roasting

The roaster only has three controls on it. One is to start, which is called “Roast”. One is to end, it is titled “Cool”. The third control is a dial that goes from 1 to 10. This will indicate the level of roasting. The higher the number the longer the roast, the darker the beans will get. Using the “Cool” stop will always stop a roast regardless of how high you set the roast setting dial.

My advice for the beginner is to set the dial to 8 and use the “Cool” button to stop the roast when it hits the level you desire. Be forewarned, if you don’t hit “Cool” it will roast approximately 1.5 minutes longer than the dial setting. As you get more experience with different types of beans, you will start using the dial to control the roast. To start the roast, hit “Roast”.

early roast

Check with the Experts

Even though this machine doesn’t require “hands on” attention, you will get the best results by monitoring the progress of each roast. When monitoring the roast you will hear the “first crack”, and if roasted long enough the “second crack”. How long should you roast a bean? This depends upon your personal taste, but if you are open to all levels of roasting, consulting a cuppers review is a great idea. Using the cupper’s advice is optional.

A cupper is a coffee professional that is trained to taste and report the distinctions of each coffee. A cupper will dissect a crop of beans and find it’s strengths and then advise a roasting level that will best compliment that bean. For example, Brazil Santos tastes great as a Full City or Vienna Roast, whereas you would roast Hawaiian Kona lighter.

I get all my cupping reviews from Sweet Maria’s. Their green bean page links directly to each crop’s cupping review. The bean roasted in this tutorial is Costa Rican Tarrazu La Minita. For this bean, Sweet Maria’s advises that it should be roasted: “… through first crack and NOT into or even to the first snap of 2nd crack. That’s where it is at its peak! “.

cool roast

Collecting The Bounty

After the dial expires or the “Cool” button is hit, the roaster will go through a cool cycle. This will take approximately as long as the roast itself. Once that has completed, pour the beans into your storage container. They will be ready for brewing in about 12-24 hours after they have had a chance to degas. Resist the urge to brew immediately.

Wrapping Up

The last step is to clean out the chaff collector (the lid). Precision provides a small toothbrush for cleaning out the chaff that collected during the roasting process. Brush away the chaff. This is a helluva a lot easier than cleaning the George Foreman Grill after cooking salmon! Don’t forget to get your smoke detector operational again after you’re finished roasting and the smoke has cleared.


Buying the Hearthware Precision Coffee Roaster is the greatest purchase I’ve ever made. The coffee I’m producing at home is on par or superior to the best commercial roasters. If the $130 price tag scares some consumers off, note that this machine will pay for itself.

Personally, I drink 1 pound a coffee a week. If green beans average $5 a pound and commercially roasted coffee averages $10 a pound then it will take 26 weeks for machine to pay for itself. The popcorn popper solution is still the cheapest, but if you are like me, living in a cold winter environment, then having an indoor roaster like the Precision is a real treat.

Michael Allen Smith

Michael Allen Smith fell in love with coffee while attending college. Shortly after graduating college, he found himself in the Tampa Bay area far away from the good coffee he had at The Ohio State University. That is when he starting home roasting coffee. Less than a year later in April 1999, he launched the coffee website INeedCoffee.com. INeedCoffee.com has been going strong ever since with hundreds of articles and tutorials submitted by over one hundred contributors.

In 2007, Michael moved to America's coffee capitol Seattle, Washington. He has visited close to three hundred different coffee places in Seattle, Portland,Vancouver and San Francisco and met many of the top roasters and baristas in the country. Since 2009, Michael has been the Organizer of the Coffee Club of Seattle, which is a Meetup group of over 800 coffee enthusiasts. Besides the social aspect of the group, the Coffee Club of Seattle partners with local coffee professionals for educational events such as coffee cuppings, brewing demonstrations and roasting tours.

Unrelated to coffee, Michael has a personal blog at CriticalMAS.com which covers several topics including fitness, cooking and economics.