Unlike other machines with boilers that take 30-60 minutes to heat water to temperature, Meticulous is dynamically heating the water in the chamber to brew temperature for each espresso. We use a combination of temperature sensors and algorithms to determine when the water will reach brew temperature. Water at different parts of the chamber are at different temperatures and mix when the piston is being retracted. For most people, only large (5°C+) differences in brew temperature lead to a noticeable difference in the cup, so you shouldn’t notice a degree or two above or below your target.