1kg is listed max. But some people push it to 1200g. I don’t think I’ll ever try with 110v though. Maybe if I had 220. If I went to 1200, it would probably need to be a low altitude dry process… maybe
I guess I will find out 
I’m in the US so 110v
Ha, I’ve had great luck doing 800 with my very dense Ethiopians and a 270 charge(I’m an American/Filipino using Metric🙃). I normally go to P9 until I’m close to yellow but I’m going to try to stop doing that. I’m happy with the Nicaraguan 1000g batch I did with a 275C charge and only briefly going to P9 and the batch I did at P8. Definitely post about your +1000 if you try it. I really only see people speak of it but I haven’t seen a full graph with people roasting 1200g
So I have been looking at cash0612’s 1kg roast and I might try their method and go from there. There is someone that roast at 1.2kg consistently, look up lav’s roast profiles for that. Whether I actually attempt a 1.2 kg batch depends on how well I “master” the 1kg. Not ready yet 
I’ve been doing a short “heat soak” at the start with P6 for the first minute with the 210C/410F ph temp.
Thai/Chinese in America using imperial for temps but metric for weight! (Lol) 
Yes those are just info, not errors. In the next release they will show as Info so users don’t get scared.
I don’t recall exactly which limits we use and it depends on what you are looking at. For the IGBT I think the warning (yellow) is at 93 C and the shut off temp is 98C or 100C / Depending on bullet version and firmware.
There are other warnings as well such as Ambient IR sensor which has other values.
I live in South Florida and always roast 1000g batches at high ambient temperatures and high P levels and to hopefully promote the longevity of my power board direct a strong cooling fan at the belly of my roaster to keep things well ventilated. Never get warnings anymore.
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So I started to roast 1kg over X’mas. The IGBT 1 read out definitely went yellow at 93. I am in the US so roasting at v110. This happened on all 4 of my 1kg roasts. I’m in Massachusetts so the ambient temp is “low” - it was around 68F inside my house and I cracked open my kitchen window as well when I roast and there is sufficient airflow under the Bullet as my vent hood draws the exhaust up and out.
I noticed the IGBT goes to yellow in just under 4 mins into my roast. My profile is such that I decrease power as I go, so by 2 mins after YP (approx 8 mins into the roast) the IGBT read out is ok. I’m on V2 of the bullet and f/w 562. So @jacob, are there any mitigation steps to take to minimize the IGBT warning? My setup is shown here Exhaust hood options - #41 by blacklabs and Exhaust hood options - #33 by blacklabs (the vent hood is 900 CFM at max setting and there is a kitchen window I open when I roast that is to the right). I plan to be roasting more at 1kg batches so it would be good to know what advice you (or anyone else) has to minimize this warning.
@miltezzard - you mentioned you roast in S. Florida, what kind of “strong cooling fan” do you use?
Thanks in advance.
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I’ve roasted a kilo of Sumatran and Nicaraguan since debugging my bullet without issue. I keep my house at 64 for pollution’s sake.
*Not really sure what happened with mine. The second fan I put in eventually worked after reconnecting a couple times and backing the screws off a tiny bit. Still have no idea why the first replacement fan managed to work perfectly well for a small number of roasts, then not at all.
So I shamelessly perch a household portable fan on a table next to my machine and direct it at the underbelly. Nothing high tech- just something to keep cool air moving over the board
Box fan by chance? 
If so I don’t have space for that in my kitchen setup, roasting on top of my stove so I can be under my range vent hood…might find a smaller tabletop fan.
@jacob, I have been roasting 500g batches of beans for a while to learn the machine. I am now starting to roast 800g batches and got error46: 98 and had the power go to P0 on a couple of roasts. I pumped the power back up to P9 after 15 seconds of P0. (Hopefully the beans aren’t scorched)
My question is: Is the board the overheating culprit? Will applying a fan to the belly of the beast help mitigate this overheating problem?
@jacob will have the answer but in the interim I’ll toss this out. Do you have the cooling tray in position under the roaster during a roast? is the fan faced under the roaster (vs. pointing off to the side)? The fan of the cooling tray turns at a setting of (I think) C3 during a roast in order to move air under the power board. It may not be enough for some reason but thought I’d ask.
Bruce
Thanks Bruce,
Yes I did have the fan in position under the roaster in the correct orientation.
I bought a small fan from Amazon and placed it where it will blow on the circuit board enclosure. I ran another roast of 800g tonight and watched the info box and the circuit board temp never went above 62C, so problem solved. I’ll run a couple of back to back roasts this weekend and see if the board gets hot under those conditions.
Another problem that I had was: when I was roassting some Natural Ethiopian beans that have excessive amounts of chaff and had dropped them in the cooling bowl, it took forever for them to cool down. I pulled the bowl and the filter in front of the fan was completley covered with chaff and had stopped the air flow. I vacuumed the chaff up and put the bowl back in to finish cooling.
When I was reading through some of the threads on Slack, I came across a thread about chaff managment and Jeromes cooling system. @Jacob said “you can remove the filter and put a bigger external filter or cloth bag for chaff collection, this seems to work well”
So, since I had a new fan on the circuit board, I took an old Coffee Bean Corral cloth bag and taped it to the back of the cooling unit. It actually worked well. The chaff went right through the fan and got trapped by the bag. I think that I will sew a new cloth bag with a looser weave material. I should be able to run many roasts before having to empty the bag. I am comfortable doing this because I now have that extra fan blowing on the circuit board.
In the photo below, you can see the fan and the cloth bag.
I do the same… run a small fan like that pointing at the belly of the roaster, but my cooling tray fan I turn 90 degrees to the right in order to fit a vent hose to direct the exhaust to my range hood vent. I didn’t want the hose running beneath in order to get max air flow below. I regularly roast 1kg now and I will still get a yellow warning for about 2 mins (and I also avoid roasting when it’s 90+ F outside).
Hah! I missed that. Makes sense. Must make cleaning the fan a pain and the bag would definitely interfere with any power board cooling from the cooling tray fan. So your Amazon fan sounds perfect. [ I once apologized to our mail carrier for all the Amazon packages. I told her ‘I’ve about got things worked out and I’ll stop buying all this stuff from Amazon’. She chuckled and said ‘don’t make promises you won’t keep!’ ]
Bruce
I don’t think cleaning the fan will be that bad. High velocity air flow and not much smoke. (I rarely go past the end of first crack)
I will get another muffin fan to keep on hand as a spare. They’re cheap enough not to break the bank.
I found some mesh bags that are used for keeping bugs off of fruit on trees and ordered some of them from Amazon. (Yeah, my Amazon delivery people love me too. lol Luckily my spousal unit can’t tell how much my green bean supply is growing… Over 200 pounds in the cupboard. )
I just ordered an extra chaf collector from Sweet Marias and already have an extra chaf filter so that I can just change out the chaf collector, hot on the fly, without losing momentum for the next roast.
I saw the bean sack and imagined a tough time moving air thru the fabric but an open mesh ought to make it easy to move the air!
Bruce
I’ve lost the links for parts ordering from Sweet Maria’s. How did you order Aillio replacement parts from them? I vaguely recall having to use the Coffee Shrub site but couldn’t locate anything there using their search tool.
Bruce