DHW coil so close to aquastat well?

This is a pretty simple question, on my KA6 I have to places for my DHW coil to be installed, previously it was the spot closest to the aquastat well, so when I put in the new coil I did the same thing. However, that water is locally cooled so quickly by incoming tap that after only a few minutes of hot water demand the aquastat calls, even though the temp/altitude gauge reads hot.

So I get that it takes a little time to get the bed heated and transferring heat to the boiler, but with 55(?) gallons of 160* (or more) water it seems like it really shouldn't be doing this. (Not sure whether the bypass loop really only helps equalize boiler temp when the circulator runs, but I do have it)
Is this a diff setting issue? Or just normal? Currently for summer operation it's at 160/140 15*diff.
Thanks in advance.

That is by design. In warm weather the fire can get very small, and take a while to start producing enough BTUs to make sufficient DHW.

I guess I am probably misjudging the time it takes to drain the heat using the coil and the time it takes to create heat from the fire. Do you agree with my aquastat settings?

160/140 is fine for the summer as long as you don't run out of hot water. Unless you have cast iron radiators I would run a differential of 10.