In anticipation of upgrading to an espresso machine that will allow me to regulate the water temp from the hot water tap, I was wondering -- what is the preferred temp of the water to which I add the shots?

To my knowledge, any water hot enough to make the coffee hot is sufficient. I just add it out of the steam boiler on my S1.
I believe only the brew temp has a significant effect on the taste. Water temp only changes the temp of the final drink.
If I'm wrong, somebody PLEASE let me know.

Jeff

I'm far from an Americano aficionado, but I've read that 185°F is the ideal temperature, assuming the cup is preheated. Steam boiler water may initially start out that temperature but rises quickly to the low 200s. Unless you're cycling lots and lots of water through your steam boiler, it won't be fresh tasting either.

If I'm making an Americano, I pour the water first and then the espresso so there's a nice looking crema. Once I tried to cheat by drawing very hot water from the steam boiler after the pour and the crema turned an unattractive spotty light brown. Ewww-w-w.

(Corrections from Americano lovers are welcome)

I adjusted the water tap temperature on my machine to very near boiling. I closed the cold water mix valve & slowly opened it as boiler water ran through. I simply stopped when the water quit flash-steaming out the spout. The PID on by steam boiler is set to 255F, a thermocouple in the water stream reads ~205F very near sea level.

I do drink americanos, but I set the temperature for my wife's black tea. (Small price to pay for consent to buy the Synesso!)

Dan,
I mainly drink Americanos, so there is plenty of water cycling through the boiler. I pull the water, let it rest a minute or so, then pull the shot on top of the water.

Turns out fabulously every time!

Jeff

I make Americani every morning for myself and my wife. I use water from a tea kettle that is just below boiling or close to the 185 Dan proposes. I agree that much higher would not be good.

My sequence is the opposite. I pull the shot and then pour the hot water on top. I originally thought this sequence would be less good than the espresso on top method. But that was based on what I read here and elsewhere. When I taste the results I find no clear preference or difference. I use the espresso first because I often use a tall cup that I need to tilt to get out from under the pf and a low volume amount in the cups makes this easier and less messy.

I find that Americani give a wonderfully pure taste profile and I love using them for focused "tasting".

KS