I have a Bullet R2, purchased earlier this year. I started seeing my roasts hit FC close to 374F/190C about 3 weeks ago. It coincided with my first 1kg batch of a specific coffee, so I assumed it was just that specific bean as a 1kg batch and didn’t think anything of it. It continued and was odd, but my results were still good so I didn’t worry about it.
I noticed that my breaker started tripping more, because I was on a 15A circuit instead of a dedicated 20A, so I upgraded the circuit over this past weekend. At the same time, I also found where the maintenance instructions say to clean the IBTS if FC temps start dropping below 383F, so I did that last night (and it was surprisingly filthy, probably from using the roaster to dry barrel-aged coffee this week; lots of ash). My assumption this morning is that the roaster will now behave like normal, but this morning I did a 1lb batch of a tried-and-true coffee that always hits FC past 390F, but it still hit at 374F and I don’t get it.
From reading on here, it looks like the control board should manage the power to the roaster consistently enough that upgrading the circuit wouldn’t make a difference in the roast; it should just keep the breaker from tripping like it used to. I was expecting the IBTS cleaning to be my solution, but I just don’t know what could be wrong. I looked at my roast log and this started on June 01, but I roasted a kilo the day prior with an FC at 393F. I don’t know what happened that next day that could have possibly caused this. Does anyone have any idea what’s up?
I don’t have an R2, but I have seen the behavior of my roasts change over time similarly to you. I have been able to control the end result, though, which is what really matters, of course.
Could you tell us more info about your setup and your roasts? What’s been your preheat temp? Have you been recording changes in ambient temp and humidity?
What’s weird is this is across all roasts, whether first of the day or last. I track temp and relative humidity, and they stay between 72-77F and 37-60%, generally. I roast in a room of my house with a window and run a hose in through the window to connect ventilation/exhaust. It’s a small room, so the temperature will rise throughout the day a bit, but it does have an A/C vent so there are no wild swings that should be causing issues as far as I know.
Here’s a log of some roasts before 6/1 and after 6/1 for comparison. If you see any trends or red flags in these roasts, let me know and I’ll try to isolate variables and play around to see if I can get the IBTS FC temp back to what I expect.
I was digging around through live roast data this morning and found in the roaster info where it says the IBTS is “unknown”. Any idea what that should say instead? Maybe something is actually wrong with my IBTS?
That is strange, I just saw another post where he talks about IBTS being “unknown” and that refering to a legacy IBTS, though I have no idea what that means.
Maybe that has something to do with it?
And why does your roaster info say you’ve 0 roasts?
For the Bullet R2, seeing the IBTS as “Unknown” in RoastTime is currently expected. The R2 firmware that supports sending IBTS information to RoastTime has not been released yet, so some information may be missing or displayed incorrectly.
This does not mean that your R2 has a legacy IBTS. You can check the actual IBTS information directly from the R2 display menu. The IBTS batch ID should normally show E140 or E200, which are newer IBTS batches.
Thank you for that info, @jedsadazisz! I see where mine is 1F-E200, so that’s good to know that it’s expected behavior for now.
@centralkycoffee I have no idea why it says 0 roasts. I’ve done close to 100 so far, but I never paid attention to that roaster info panel before so I’m not sure if that counter ever started going up or if maybe it’s more like a session counter where it’s the number of roasts since last power on. I’m going to try to roast some this morning, so I’ll watch and see if it changes at all.
