I am at P=325, I=3, D=4 right now. Stability is still problematic when the shot pace is too fast or there is too much flushing. The problem is nothing that can be solved by settings tweaks; the pump signal interferes with the probe reading, and that screws up the PID control and also the display temperature. For now, the best you can do is minimize flushing and pace your shots out to give the system some time to stabilize.

Are you actually having a real problem, or are you just frustrated by the numbers you're reading on the display? For what it's worth, the output at the group as measured by a thermofilter is more consistent than the display reading, as you would expect. It's not a GS/3 for temperature consistency with this bug, but... it makes great shots for me and doesn't struggle with doing so consistently. So, again, are your shots actually tasting different from shot to shot, or are you just worried by the display temperature moving around too much?

erics wrote:You are being too kind. Calibrating the thermofilter designed by Greg with a given meter is very easy.

Speaking of "being too kind," I wanted to post some perspective I got on Thursday of this week. I have a GS/3 AV on loan at my house, working blind taste tests for the Slayer review. Anyway, I was very surprised to find that the GS/3 was delivering shot temperatures 3-4 F° above the display temperature/offset-adjusted set point (bear in mind, the "set point" adjustment isn't offset-adjusted when looking at in the programming interface on the GS/3). I was reminded that you shouldn't trust the display temperature of any machine that hasn't been explicitly tested with a thermofilter that was recently calibrated.

Yes, I'm just worried by the number on the display. The quality I get from Slayer's shot is much better than my previous machine, Expobar Brewtus III. However, I sometimes feel the temperature of coffee is a bit cold, by tasting it (I definitely preheat every cup with hot water tap). I sometimes feel I should get more body. There is a lot of variables, profiling, temp, dose, grind, my consistency, coffee change. If the temp reading is more reliable, that would be one step easier.

What about your brew temp offset?

shadowfax wrote:I am at P=325, I=3, D=4 right now. Stability is still problematic when the shot pace is too fast or there is too much flushing. The problem is nothing that can be solved by settings tweaks; the pump signal interferes with the probe reading, and that screws up the PID control and also the display temperature. For now, the best you can do is minimize flushing and pace your shots out to give the system some time to stabilize.

Are you actually having a real problem, or are you just frustrated by the numbers you're reading on the display? For what it's worth, the output at the group as measured by a thermofilter is more consistent than the display reading, as you would expect. It's not a GS/3 for temperature consistency with this bug, but... it makes great shots for me and doesn't struggle with doing so consistently. So, again, are your shots actually tasting different from shot to shot, or are you just worried by the display temperature moving around too much?

waroros wrote:What about your brew temp offset?

This can't possibly mean anything to you. My offset is unique to my machine's probe and brain, accounting for the offset itself (difference between measuring location and water at the group) as well as the offset between the probe reading and the true temperature. This is not guaranteed to be identical between machines, and indeed probably isn't, ever. If you want to set your offset so that the set point/display temperature is accurate to the delivery temperature, you need to get a thermofilter that is accurately calibrated in a steam bath.

I think it's a good point that if you are going to compare numbers, any temperature measurement system needs good calibration (and re-calibration). On the other hand, if you want to just get close and then tweak to taste, it's not critical.

Offset between measurements somewhere inside the machine and in the portafilter under various environmental and use conditions is a good question - it's more variable than many think. Even more so if you start measuring what the coffee experiences (ie, inside or below the puck).

jonr wrote:On the other hand, if you want to just get close and then tweak to taste, it's not critical.

Yes, this is a really important point. I got a Scace 2 recently, and my coffee isn't any better-I am just using a different display temperature that is more accurate to the temperature at the group. Before, I would pull shots at what I thought was 203°F, when it was actually more like 199-200°F. This doesn't matter except for comparative communication, which is only transferable to other machines calibrated properly with a Scace thermofilter. In reality, as a barista you shouldn't care one whit. The point is to find the correct temperature for brewing your coffee. This is such a dynamic thing, you have to do it by taste and trial and error anyway. So I wouldn't worry about it for the most part.

shadowfax wrote:The problem is nothing that can be solved by settings tweaks; the pump signal interferes with the probe reading, and that screws up the PID control and also the display temperature.

That's very interesting. How was this determined? Is the manufacturer working on a resolution to the problem?

no update for so long

all the slayer threads and reviews have gone very quiet...

any updates for a long awaited fix?