Amberale One is over boiling point while the other is under but surely the water in the steam boiler doesn’t actually boil while under pressure.
I believe by definition for water to be given enough energy to make the phase change from liquid to steam it has to boil.
In the typical brew water heater the water does not reach the boiling point or make the phase change, remaining as a hot liquid.
I assume the phase change is what we hear, assuming no leaks to create that other, annoying, hissing sound 🤭
to be clear, i’m not suggesting we should hear anything once its in a steady state, only after steaming or pulling water with the heater constantly on, or on the initial warm up once above 99 red balloons!!
