My Bullet was delivered as V1.5. My IBTS fan worked the same way yours does from the day I received the Bullet in January. When they introduced ErC 6864 through fan speed measurement in FW 540 (537?) the failure was immediately identified- my problem was there all along. I had assumed the slow IBTS fan speed was the result of built-in speed control based on temp (perhaps IBTS Ambient). Wasn’t till ErC 6864 came along I learned the fan is supposed to be at max speed as long as power is applied.
My sense of fan operation on my Bullet was that startup speed was 4,000 - 5,000 rpm till I started roasting when it would move up to 10,000 or more rpm and would settle out at about 15,000 - 16,000 rpm. Colder weather made it run slower. Since I roast outdoors, ambient affected fan operation… except it isn’t supposed to do that.
I’ve not yet contacted SM regarding the fan, as I’ve come up with a solution that seems to work.
When I first plug in the machine, I start the pre-heat immediately. (running 540 by the way). I get the 6864 error code after about 5 seconds. I cycle through the controls (load.roast.cool.off) and let the machine sit for about 30 seconds. Then I start the pre-heat again. At this point, the fan starts spinning at about 6,000 RPM, ramping up t o about 13,000 rpm shortly. The pre-heat and roast proceeds normally.
I just worry that the fan is showing signs of distress. I would hate to be without the roaster (as I gave away my old Hottop and don’t have a back-up) if the fan fails completely.
Does anyone have an idea about a progression to failure?
They added a 20 sec delay to the test for fan speed at start-up, but that delay goes away during a roast. As long as you can get above (and stay above!) the minimum in that time (>5,000 rpm?) the fan will probably warm enough to get the speed to stay above that minimum. Mine was worse than yours initially so it didn’t have as far to go to fail. The delay he added didn’t make any difference in my case. The failure of my fan was of steady decay (vs. a sudden failure). But I’d get that replacement on the way before too long. We’re all spoiled and can’t go long with bad coffee!
Sorry… haven’t been able to keep track of f/w releases. I scanned back thru roasts where I (inconsistently) keep note which s/w & f/w I used for the roast. I’m sure the error detection preceded 540 and I think it preceded 538 (11/2019?), but the delay was part of f/w 538. It’s been awhile. The post from @jacob related to ErC 6864 (Message #2 above) says…
If you’ve gotten this error, you probably need to start the dialog to get a replacement fan on its way. Takes time to get it and to get yourself informed enough to tackle the installation.
Some folks have fan blades barely visible under the coffee crud. Mine was clean as you describe yours. The f/w monitors rpm and (I think!) temp. Those 2 items generate the error code when they fall out of range. The ambiguity in any built-in-test is that the error can be either the device being measured or in the measuring device. You need support to help figure that out.
