Bullet unexplained behaviour

My Bullet did something very strange yesterday. I set it up to preheat to 275 DegC and it started the preheat process normally.

However, after 15 minutes or so it just jumped into roast mode by itself and with no input from my side whatsoever. It was not even connected to the computer yet.

Lucky I was nearby to quickly stop it before it overheated and fried itself.
After that I started another preheat to 230 DegC and did 4 roasts with no further issues.

My question is; what would have caused my machine to enter roast phase from preheat by itself and has this happened to anyone else here?
Also, is there anything I should do to avoid this happening again as it could be catastrophic.
Thanks in advance

Hi Gaby,

The Bullet senses on the bean probe and the IBTS. If any falls below a threshold it will trigger the roast to start. If there was a large gust of wind on the front if might be able to trigger it. Another way is if your bean probe is beginning to fail. You can see this in large spikes of the ROR / Bean temp while roasting.
If it happens and you are not there then the Bullet will shut down by itself if it gets too hot, so it will not break anything.

Thank you Jacob,
It was a windy day so could very well have been a gust of wind that caused it.
Glad to know there is a scientific explanation for what happened.
For a while there I thought my machine was possessed :grin:
Kind regards

@jacob further to my earlier reply, would you be able to look at my last 4 roasts and let me know if the spikes on the ROR (bean temp probe) look normal to you or whether they suggest a failing probe?
Would greatly appreciate your feedback.

Thanks in advance and best regards
Gaby :blush:

Hi Gaby,

I had a look at your profiles and everything looks great.
If it happens without gusty winds then let us know again.

Bless you Jacob :pray:

This happened to me quite a while ago when I opened the door to wipe off the glass during pre-heat, which dropped the temperature and triggered the Bullet to go into roast mode. I make sure to clean the door before I start pre-heat now.

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