Celsius or Fahrenheit?

I’m just curious which temperature convention do people generally use, C or F, when roasting on the Bullet?

Previously when roasting on the FreshRoast I’ve used a K-type themocouple probe threaded through the chaff collector and had set it to F.

Good question. One VERY nice feature of aillio/bullet/rt/rw software and hardware system is the ability to switch freely back and forth between C & F. I do it all the time. Furthermore, if somebody roasted in F and you like C, when you view their roasts on RW they appear in your preferred system C. Nice work @jacob @matthew @derrxb !


I use C, even though I live in USA. It seems like a silly decision now, most of the articles/books/videos I come across use F.

I’ll probably switch to F.

Thanks @bradm and @damon. I think I’ll probably set mine to F since I also live in the US and am use to thinking in F (even though I grew up with C and the metric system) when I roast.

Good to know the software can easily convert the display.

@blacklabs - you’ll have to set preferences in RT3 of course but you can also set preferences in R.W (Dashboard → profile (upper right) → Edit) where you can choose F°/C° & kg/lb-oz.


C ! join the international community, don’t be afraid.

F offers a little more granularity in tracking temps but 200 C first crack is just so nice.

After thinking about this a little, perhaps the easiest way to decide C° vs. F° is to consider what you do before you go outside. You probably start with a look at the outdoor thermometer. If the answer is something like -5°C then set the Bullet to Celsius; if the answer is 23°F then use Fahrenheit. You shouldn’t have to change your life to roast your coffee.



I completely disagree. Roasting coffee can change your life :grin:

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Ha. For over five years, I roasted in F, until I bought the Bullet and joined this community, where everyone was posting in C. So I switched to C. Make no mistake, we look to hit targets we’re familiar with, so it does make a difference. But I suppose I’m getting to be bi-lingual now. Ha. That RW feature of viewing in either/both is something I wasn’t aware of, or came after I joined. Sweet.

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I know the landmarks better in C but F gives you more degrees between two given temperature points. So for me, at this stage (i am a new bullet user), I find F more useful to create or test recipes. Once I will have my recipes correctly, I will switch to C. (and as someone mentioned here it is easy to switch from one to another).

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