With a smaller HX, what is a normal temperature drop over the course of a shot?

[quar]

When using Eric S.'s adapter with a chopped down thermometer installed in my Anita, I'm trying to get a good understanding of where my finishing temp should be. I've seen the chart that Cannonfodder posted showing how the GH and puck temperatures converge around the 16-20 second mark, but I start dropping in temp shortly after that. For example, my conventional shot spikes to 206 at start and starts falling back to level out around 201 at the 16 second mark, by 30 sec (ristretto) temps may be down to 198 or slightly lower. Other graphs that I've seen posted seem to show a tighter temperature range. Is three to four degrees over the course of a shot normal for a machine like mine? Seems to be a bit more pronounced with a ristretto.

Mike

[cafeIKE]

The Andreja OPV is on the output of the HX, so more cool water flows through the HX than on a machine where the OPV is before the HX.

This contributes to the shot profile difference.

There is no firm data on what profile makes a great shot, so it's not something to lose sleep over.

[Elbasso]

Other graphs that I've seen posted seem to show a tighter temperature range. Is three to four degrees over the course of a shot normal for a machine like mine?

When you look at the graph below you'll see that the temp measured by Eric's device is a lot higher then the temp measured at the puck. Furthermore, the bottom two lines show that the temp at the coffee is pretty solid during the shot even though the temp you measure with your device is dropping from 207 to 201. The rule of thumb seems to be that after about 12 seconds into the shot you can derive the actual temp at the puck by subtracting about 5 F from the temp measured with Eric's device.

[quar]

Yes, I was aware of the convergence of the group temp and Eric's device in the last third of the shot. It was the increasing rapid decrease in temperatures at the very end of the shot that was bothering me. CafeIKE has the explanation, with how the Anita's OPV is configured, I'm running bit more water through the HX than other machines.

Mike