No manual control with firmware 540?

While doing a roast to test a replacement control board I received recently, I found myself fighting the roaster to keep the power and fan settings where I wanted them. The board came with v540. The version I was using on my old control board was from March or April of last year.

Did something change in the firmware that forces some sort of auto mode?

I’m not aware of anything in the f/w that would interfere with how you control the roast from either the control panel or s/w. There are some BITs (built-in test) that look for out-of-range data, e.g. checking the minimum IBTS fan speed or continuing Preheat till Bean Temp stabilizes even though Drum Temp has hit the target.

I’ve used f/w 540 since it was released though I did have a bad d/l the first try.


Thanks for confirming that this behavior is unusual. I’ve had notihing but troubles since I replaced the control board a few weeks ago. I’m convinced that the used replacement board that SM sent me is defective.