Pre-Heating the Behmor Coffee Roaster: What to Know About Warming Up Your Machine

Our guide to pre-heating vs. not pre-heating the Behmor coffee roaster and what to expect.

A topic that comes up a lot with Behmor owners is whether or not to pre-heat the machine before roasting. Some say it improves cup flavors, others call it a waste of time. One thing’s for certain is that it shortens the overall roast times, which will have some impact on the cup.

After spending some time testing the thresholds on an upgraded 1600 Plus (same features as a 2000 AB Plus), and speaking to Joe Behmor himself on this topic, we’ve compiled a list of answers to some commonly asked questions below that we hope will help you decide whether or not to add the extra step of pre-heating your Behmor your coffee roasting regimen.

Pre-heating basics – things to know:

What does “pre-heating the Behmor” mean?

Pre-heating any roaster simply means warming up the machine by starting a roast cycle without coffee. Most production roasters require a pre-heating period for warming internal parts, which often includes a steel roasting drum that takes a while to come up to temp. For the Behmor, it’s a way of “waking up” the roaster, affording you a bit of a running start.

Do I have to pre-heat the Behmor to get a good roast?

Absolutely not! All of the Behmor roaster models are more than capable of producing great tasting roasts without pre-heating the machine. Pre-heating the Behmor is one way of shortening your overall roast time. Whether or not you do so should be based on personal preference.

What’s the safest way to pre-heat the Behmor?

Before starting the pre-heat cycle, I remove the drum from the roast chamber and pre-load my roast batch. I warm up the Behmor with the chaff tray only, starting the roaster in manual mode on the highest heat setting of <P5>. When the Behmor reaches the desired pre-heat temperature (monitor the roast chamber thermistor by pressing the <B> button), I stop the roaster, remove the chaff tray, insert the pre-loaded drum and re-start my roast as normal.

checking the roast chamber temperature while pre-heating the Behmor coffee roaster
checking the roast chamber temperature while pre-heating the Behmor coffee roaster

Is this pre-heat cycle dangerous?

No, not really. The inside of the roaster will be hot, so take care pulling the chaff tray and loading your wire grid drum so as to not burn yourself. I use gloves or a towel to manage the hot chaff tray. You can also remove the chaff tray before warming up the machine, but the cold metal will cool down the roasting chamber some when loading into the hot machine.

How does the pre-heat cycle affect roast dynamics in a Behmor?

Depending on how long you warm up your roaster, you can shave a minute+ off your roast time. It may not sound like much, but it can certainly improve cup dynamics if that’s the sort of flavor profile you’re after.

How hot can I safely warm up the roaster?

Most Behmor coffee roasters can be pre-heated to 250 F, or somewhere around 3 – 4 minutes. (On my upgraded Behmor 1600 Plus, 3 minutes on the highest heat settings gets me to 200 F).

What happens if I try to pre-heat the roaster beyond 250 F?

Pe-heating your Behmor past 250 F forces you to run the cooling cycle before starting another roast. Obviously, this defeats the purpose of warming up the machine! One thing to keep in mind is that electrical heat continues to ascend after switching it off. This means you need to stop the pre-heat cycle before your Behmor hits 250 F so that you don’t pass the safety set point threshold.

Will pre-heating the Behmor harm the roaster?

No, pre-heating the Behmor shouldn’t have any negative affects on the roaster’s internals as long as you re-start your roast. If you decide not to start your roast, make sure to run the cool cycle in order to cool the roaster down completely.

The Behmor wire grid drum used across Behmor platforms
The Behmor small grid drum used across both 1600 and 2000 iterations of the Behmor coffee roaster.

How will pre-heating affect the cup flavors?

In general, a faster roast leads to a more dynamic cup profile. There is such a thing as roasting too fast, but you won’t have that problem with the Behmor. Setting out to roast faster should coincide with roasting light. Coffees that can benefit from this roast style are those with potential for acidity and top notes, like African coffees and Geshas for example. Roasting these coffees too dark will mute much of what’s special and interesting, as will roasting them too long.

Are there coffees that benefit from not warming up the Behmor?

I would not pre-heat my Behmor for softer, low density coffees. They will benefit from less aggressive heat application, the slower roast progression helping to develop sweetness without risking the roast getting away from you. These tend to be lower altitude coffees grown below 1500 meters, like Brazil and many of the coffees in El Salvador and Honduras. Also, if you’re roasting blends, or roast dark in general, I would also skip the pre-heat step.

In short, whether or not you pre-heat your Behmor is really up to you and will depend on what you’re hoping to taste in the cup. If you want to highlight top notes and acidity in a light roast, I say give it a shot and see if you can taste the difference. Especially if you’re not getting the dimension that you’d hoped for. But if it’s the deeper bass notes of a dark roast that you’re after, pre-heating the Behmor is unlikely to produce any discernible difference.

Pre-heating is only one way of shortening your roast times. If you’d like to learn more about our approach to light roasting in the Behmor coffee roaster, check out this blog post.

If you’re interested in getting a nice dark roast in your Behmor, here’s a list of our recommendations.

21 Responses

  1. Which is it? In this article, “starting the roaster in manual mode on the highest heat setting of .”
    And in the Dark Roast article, “On their own, they won’t generally allow enough time for coffee to reach 2nd crack, even using P1, the highest heat setting”

    So P5 or P1?

    1. Thanks for pointing that out! In the dark roast post, I should’ve written “on P1, highest preset roast profile”. The P5 setting in manual mode is burner on 100%, and the hottest possible setting in the Behmor. I’ve updated the dark roast post and hope that clears up any confusion.

      Cheers,
      Dan

  2. I roast with a Gene Cafe drum roaster; never-the-less, I find I get more consistent and repeatable roasts with a pre-heat cycle.

    1. That’s interesting to hear Bruce. I honestly don’t have that much experience myself with the Gene, but will try pre-heating out on that machine next attempt. Care to share your method?

      Thanks for the note!

      -Dan

  3. I used to preheat with the basket and chaff tray in the Behmor. Handling the hot basket was much more difficult. So now I preheat with the basket out, for 2:50. Then if I pull the chaff tray out with mitts, I can put the basket in bare-handed, which is much easier. I find preheating allows me to more comfortably slow down the roast as we go into first crack.

    1. I used to do the exact same thing and took me a few burned fingers to realize that I could just keep the drum outside during the warm-up. Haha. That’s an interesting note of having more control during 1st crack with a pre-heat cycle, and I have no explanation for that. I would think that a faster rate of rise would have the opposite effect, but sounds like that’s not the case for you.

      Drum speed might also help with controlling 1st C to some degree depending on batch size. We use the fast drum speed through the drying phase at the very least to keep the coffee high in the drum and closer to the heating elements. Perhaps slowing the drum speed once the beans become exothermic could lead to a faster 1st C if the bean bed were large enough….haven’t tested that.

      Here’s an older blog post and video Tom did on roasting with the 16 vs 32 rpm drum speeds when Behmor first upgraded the motors.

      Behmor Coffee Roaster Drum Speed Comparison

      Thanks for chiming in on the thread!

      -Dan

  4. Thanks for the update on preheating Dan. I received a 2000 AB as a gift recently after roasting on a 1600 plus for years. So far the biggest difference seems to be noise volume from exhaust fan and drum speed motors. Both a good bit louder. My first couple of roasts were not my usual results. It seems the faster, louder drum roll and exhaust fan threw me off a bit. Hearing 1C took some getting used to the new dynamics. Since the upgrade in drum speed ( 16 to 32 rpms ) is one of the 2000 ABs developments, I wanted to hear your input on how best to use the additional drum speeds. Thanks

    1. Hey Steve,

      That’s interesting about the motor and fan noise. I need to go back and look at the specs on the 2000 AB, but didn’t think the exhaust fan changed. I only have 1600 Plus Behmors that I upgraded with the new motor and control panel. Whatever the case, I’m glad to hear you’ve been able to adjust to the 2000 AB, and hope you’re happy with roasting capability.

      On drum speed, we’ve been using the faster drum speed to keep the coffee higher in the drum, and closer to the heating elements. Keeping the coffee physically closer to the heating elements should make for a faster rate of rise. The only exception I can think of is when the beans become exothermic at 1st C. I would think slowing the drum speed with a larger bean mass would cause a more rapid 1st C.

      Here’s an older blog post and video Tom did on roasting with the 16 vs 32 rpm drum speeds when Behmor first upgraded the motors.

      Behmor Coffee Roaster Drum Speed Comparison

      Thanks again for your comment and question!

      -Dan

  5. Hello Dan,

    Thanks for the post. Your posts and comments are very informative. I have roasted with Behmor around ten times, and I love the machine! Before this, I had roasted coffee on the stovetop, but Behmor is much easier and much more consistent.

    I’ve been using the suggested profile for my city+ to full city roast, which uses the manual mode, starting with P5, and dropping it to P4 or P3 at 1st crack. This method works pretty well. I try to adjust the timing of the power change depends on how beans react during 1st crack.

    To improve my roast, I’m trying to connect what I’m experiencing with Behmor to general roasting know-how.
    To gain more knowledge base to improve my roast, could you elaborate more about what is happening in Behmor specifically by each roasting stage? (In maybe your future post?)

    For example,
    – Drying stage: P5 = strongest heat + no fan = what’s happening in Behmor? What’s different from commercial roaster?
    – Pre-1st crack: P5 = strongest heat + fan (around yellowing stage) = what’s happening in Behmor? What’s different from commercial roaster?
    – Post 1st crack: P3 ore P4 = weaker heat = what’s happening in Behmor? What’s different from commercial roaster?
    – after 1st crack: cooling in the drum = Are you using this time for development?

    I’m basically trying to understand why the profile (P5 -> P3 or P4) works well in Behmor.

    I have two more specific questions.
    1) I just wonder, but does the fan speed change during the roast?
    With my 2000AB, 1/2lb mode, I start hearing the fan around 5 min mark, and the sound becomes louder 1 min later.

    2) I use 1/2lb mode for manual roasting while you use 1lb mode. Are there any differences between these two when roasted manually?
    I’m not so sure, but the timing of the fan kicks in maybe different.

    Thanks again for great resources!

    1. Hi there Yuji,

      I’m glad to hear you’re enjoying your Behmor! In comparison to stove top roasting, the Behmor has such a different feel, and probably a relief to not have to spin that Whirly Pop by hand 🙂

      “What’s going on in the roaster” is a really good question, and the knowledge that comes from understanding the different roast stages can help to inform and improve your roasting. Even on the Behmor! I say that last part because the Behmor does have its limitations. I recommend using the maximum heat settings in order to achieve a relatively short overall roast time. If you don’t, you risk a long roast, potentially ‘baking’ the coffee which leads to a flatter cup.

      The Behmor is not like most production coffee roasters, so it’s really hard to make a comparison. On our 12 kilo Probat, for example, we’re able to employ a much more varied heat profile without risking baking the roast. Gas heat and a solid steel roasting drum allow us to make more dramatic shifts in heat input, so I’m not tied to a single option to hit my marks.

      As far as “what’s going on” with the coffee during the roasting process, it’s going to be the same across all roasters for the most part. I guess how the coffee is affected by the different variables – heat, air, time, etc – is what will differ the most, which is where you, the roaster, come in.

      One of our most popular blog posts is Using Sight to Determine Roast Degree. In it, Tom uses macro images of the color changes in coffee during roasting to help illustrate the different stages in the roasting process. I think you might find it useful if you haven’t already stumbled across it!

      To your last question, I’m really not sure! I have a few tests to run on my Behmor later this week and made a note to see when the fan kicks in running 1/2 LB setting and manual mode. I assumed it was always 7:30 in, but maybe not the case. I’ll circle back after testing.

      Thanks again for your questions Yuji! I hope my answer helped, but please feel free to reply if I can further clarify anything.

      Best,
      Dan

  6. Hey Dan,

    Thanks for this post. I’ve recently gotten back into home roasting after a long break and upgraded my old 1600 with the newest panel, board, and motor. I’ve been roasting in manual mode and have been pretty pleased with the results I’ve gotten so far, making small changes from one batch to the next to see what I can improve. Your articles about roast development and tips for the Behmor have been invaluable.

    In regards to pre-heating, I read an article from another home roasting blog that advocated for a REALLY hot pre-heat cycle – anywhere from 250-280 on the B sensor depending on bean and preference – and using the 1 lb manual setting for the main roast (batch size ~250g-300g).

    Here’s what I thought was unusual and wanted your opinion on: The post’s author uses NO power for the first full minute of the roast. They preheat, load the drum, start manual mode, and immediately drop power to P1 until a full minute has elapsed. Their reasoning is that it is supposed to emulate a heat soak of a larger commercial roaster when the drum is charged.

    Thoughts on this? I’ve not experimented with it yet, but it seems to run contrary to everything I’ve read up to this point about starting with an aggressive heat ramp at the start of the roast.

    Thanks again for all you do!

    – Dustin

    1. Hey Dustin, welcome back! Glad to hear you’ve broken out the old Behmor and even upgraded it with the panel, board and motor. Manual mode is truly an improvement to the pre “Plus” models in my opinion.

      With regards to soaking, it’s my opinion that it greatly depends on the coffee. Soaking makes a lot of sense in a production roaster where the flame is directly below the steel roasting drum. A really high flame will mean a really hot drum, and can certainly lead to scorching. It also makes sense for roasting low density coffee, like Brazil, for example. Low density coffee can benefit from a longer drying phase, allowing the coffee more time to find equilibrium with the chamber temp, gently developing the roast so that the sugars caramelize without burning.

      I’ve not tried this approach myself, but will give it a whirl with a Brazil and compare the cup differences with my standard high heat approach.

      Thanks for the note!
      -Dan

  7. I’m still learning my Behmor which I bought earlier this year. I have read and heard references to the fan kicking in. I have never heard this, even when A and B temperatures reach more than 400F and 300F. Could my machine be faulty?
    When I press the 1lb button the time goes to 18:00, but on then pressing P5 it goes to 23:00. Is this what should happen?
    My machine has never shut down for high temperature, even when preheating to A/B 480/320 which one video suggested.
    It does however switch from Manual (flashing P5) to Auto (steady P5) at high temps.
    It’s all a bit confusing and your comments would be welcome.

    1. Hi Peter,

      If you bought the Behmor earlier in the year, I’m assuming it’s the current 2000 AB. I’ll do my best to address your questions one at a time, but please feel free to reply with any other issues your having, or if any of this needs further clarification!

      Fan – this should kick in mid roast, which on the 1lb setting is 7:30 in (11:30 on the LED). It’s not super loud, but you should hear it if you pay close attention, and can also see proof of effectiveness by the dip at the internal temperature thermistor (B button), and sudden increase at the exhaust temperature sensor (A button).

      The 1lb. setting should bring up an 18 minute timer, and yes, hitting P5 before hitting the start button increases that by 5 minutes for that particular profile. If you hit the start button first, and then hit P5, this takes you into the manual roast mode (indicated by the blinking P5 on the LED – which I see you’re well aware of!).

      The overheat issue seems to have been remedied on the 2000 models, as well as on 1600’s with the upgraded panel. I need to update those blog posts with that info, so thank you for pointing this out!

      Your roaster should not automatically switch out of manual mode. Can you note at what temp this is happening and reply with that info? I’m hoping that it’s just a fluke and not a regular occurrence.

      Hopefully this helps demystify things a bit. The Behmor has a TON of options and different combinations, which can make finding a good baseline tricky.

      We’re here to help, so don’t hesitate to shoot any other questions you have.

      Thanks!
      -Dan

  8. Hi Dan,
    Thanks for your reply. I just did a dry run (pre-heat, no beans), pressing , , then recording the A and B temperatures at intervals. Here are the results:
    Starting at 18:00 and 72F for A and B.
    All times are the remaining times on the display.
    Steady increases up to 11:30, A98F, B323F.
    Shortly after 11:30 the heating elements went dark, P5 was still flashing on the display.
    Around 10:40 (remaining) the elements came on again and stayed on for the remaining time.
    At 10:00 remaining, the temps were A226, B296.
    Then all was normal, heating elements stayed on.
    At time 00:00 the drum stopped and the display showed “Err 2”.
    There was no “Cool” displayed but I could hear the fan going.
    I switched off after 30 minutes, at which point the fan was still going, the drum was still stationary and the display was still “Err 2”.
    I never heard the fan start, but my hearing is good and I always hear 1st Crack. I could hear it clearly once the drum stopped at time 00:00.
    I did note that the temperatures changed at display time around 10:00 from A/B 104/314 to A/B 226/296, indicating that the fan came on as you predicted.
    I hope all of this makes sense to you. I will be happy to do more tests.

    1. Hi Peter, this is all a bit mysterious.

      I’m going to jump to the end of your email first. Don’t let the roaster sit if it’s stopped for any reason during the roast due to an error. If you can’t engage the cooling cycle by simply hitting the cool button, try pressing Off > then Cool, or cycle the machine by unplugging/plugging back in, and then hitting cool. Whatever the case, you should start the process of pulling the heat out of the roaster instead of letting it sit stalled, hot.

      Can you confirm which Behmor model you own, and whether you bought it new or used? Is the door black (1600AB or 2000 AB) or silver (likely 1600 Plus)?

      If you have a 2000AB Plus, you should hear loud beeping and the LED will start to blink with around 4:30 left in the roast (75% into the cycle), and you would need to hit the start button to continue roasting or the Behmor will shut down. This is the Auto Safety/Unattended Shutoff feature (Err7 if you don’t hit Start).

      I’m guessing you have an older 1600 Plus because you didn’t mention this. Plus, the 2000 series doesn’t generally achieve temps much higher than 300 unless pre-heated. In an 18 minute roast, your fan should kick on with 10:30 on the LED, or 7:30 min into the roast. This would explain the lower temperatures, but I’m surprised it was not audible.

      Err2 is related to high heat. I would expect this around 320-325F, not at the lower temps you cite toward the end of the roast.

      If you could answer these questions we can try to help you troubleshoot a bit more.

      The manual answers some of these questions too, so I will link to them here. There’s a lot of really great info on how the roast cycles + manual mode should play out, general maintenance, error codes, etc. We’re also happy to answer questions, but just in case you don’t have one handy.

      1600 AB manual
      2000 AB Plus manual

      Sorry you’re having trouble with your machine! Hopefully we’re able to determine if it’s functioning normally or not.

      Best,
      Dan

  9. That should have read “pressing 1, then Start, then P5 then recording the A and B temperatures at intervals”

  10. Hi Dan,
    I don’t think my last message went through so I’m resending.
    I got the roaster from sweetmarias.com in Feb 2021. The labels say:
    Model TO9500TC-UL Serial # B2000BXBZ12151AB
    I don’t think it was actually stalled, the fan was going although heating had stopped and Err2 was displayed instead of “Cool”. The fan continued for 30 minutes until I switched off.
    I have since used it yesterday and again today, with normal results roasting 8oz each time. Both times I preheated for 6 minutes without the drum. At 6 minutes the A/B temperatures were 96/321 yesterday and 95/303 today.
    By the time I got the drum in and started the roasts the temps were 138/240 and 134/237 yesterday/today.
    All was good. I assume the strange results before were due to letting the preheat go too long and exceeding safe temperatures.
    It does seem that the machine does not actually shut down at high temps but merely stops the heating. When this happened, as reported before, it was after an extended preheating to 482/312 and occurred during the subsequent roast. I was able to return to Manual and continue the roast by pressing P5 again.
    I think all is OK and I just need to avoid excessive preheating.
    Do you think 6 minutes preheating is excessive? The exhaust temperatures rose by about 40 degrees while I inserted the drum with the machine off, but only to around 138F.

    1. Thanks for gathering that info Peter and doing a little more testing. It sounds like the roaster is operating more in line with how it should, but I’m still a little mystified by the error and shutdown with the fan running for 30 minutes. I don’t think that’s something I can replicate (or would want to, to be honest!). As for preheating for 6 min, if you’re able to without having to cool the machine and are happy with the results, I say go for it. I didn’t think you could pre-heat the 2000 so high. I’m going to test the threshold on mine later today.

      Shoot me a direct message when you have a second and we can continue the conversation in email.

      [email protected]

      Thanks again!

      Dan

  11. Can someone clarify a few things in the Behmor manual for me?
    1.On page 6 it says P1 is “the hottest profile” and “P5 is the the most delicate of the profiles, the slowest roast time”. Page 8 also states that P1 is the highest heat profile and P5 the lowest.
    But on page 9 P1 is shown in a table as 0% power and P5 is 100%.. So, is P1 the hottest or the coolest profile?
    I would also appreciate knowing the difference between Profiles (buttons P1 – P5) and Programs (buttons A – D).

    1. Hi Peter,

      Thanks for your questions. While the Behmor is likely my favorite home roaster in its class/price point, it’s pretty easy to get bogged down by all the different options! When roasting using the automated profiles, P1 is the hottest profile, P4 a notch lower/longer, P3 lower, continuing to P1. But when roasting in manual mode – where you are allowed manual control of power and drum speed – P5 is the hottest at 100% power, P4 75%, P3 50%, P2 25% and P1 is heater off.

      The Program buttons have changed on the latest models, and are: A chamber temp, B exhaust temp, C “rosetta stone” time reset, and D drum speed (toggles between 2 speeds).

      The idea behind those different profiles (P1-P5) is that coffees of different densities and moisture require different heat application. While there’s a lot of truth to that, in my opinion, the Behmor roasts can go a bit long, even at the highest heat settings, so roasting too fast is never an issue. Personally, I always roast at the hottest settings no matter the coffee. Here’s a Behmor panel cheat sheet we put together that’s handy to keep by the roaster, and a video on roasting light that goes over roasting in manual mode.

      Happy to answer any other questions you have!

      -Dan

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Related Posts