Radecki82 HX with PID (fresh water instead of helding water in a boiler
A slightly misconception. The Heat Exchanger is no different to a boiler - just that the water is heated passive via the main boiler. You’ll have 150ml/200ml of “old water” in there, of course, unless you flush 200ml or whatever before you start your coffee session and wait for the machine to rebound. In such a case, I would personally forget the fancy HX machines and just stick to a box standard HX machine: Simpler, and less to go wrong.
Radecki82 Doing 3-4 espresso/americano in a daily manner
I’m sure you know this already, but you use the tap water for the Americano, then that will come from a boiler anyway. You are better off using that water to warm the mugs, and have fresh water from the kettle for your drinks. 👍