BrewCraft Flux

The Flux is a heat-exchanger (HX) machine: one large boiler held at steam temperature, with fresh brew water drawn through a tube passing through that boiler on its way to the group. That means you can steam milk and pull a shot at the same time — the big advantage over a single boiler — at a lower price than a true dual boiler.

• Boiler: single heat-exchanger
• Portafilter: 58mm
• Steam power: high (large boiler)
• Simultaneous brew + steam: yes
• PID: steam pressure only

The trade-off is brew-temperature precision. After the machine sits idle the water in the HX tube overheats, so the first shot needs a short cooling flush — run water through the group for 2-4 seconds until the temperature settles. See Machine Types for how HX compares to single- and dual-boiler designs. A great pick for latte/cappuccino drinkers who don't want to pay dual- boiler prices.