La Marzocco GS3 AV

The GS3 is a dual-boiler, single-group machine: a 1.5-liter boiler for coffee and a 3.5-liter boiler for steam, kept separate, feeding an exposed saturated group instead of one tucked behind panels. The pump sits inside the chassis, a choice built for home use. A pre-heating system brings the water close to coffee-boiler temperature before it gets there, shortening the wait between one coffee and the next, and insulated boilers help hold the temperature while cutting energy use.

On the AV, dosing is electronic: a keypad with four buttons lets you program four different doses, each with its own pre-infusion. A dual PID governs coffee and steam boiler temperatures separately; a digital display shows temperature and each coffee's brew time. Two front-facing gauges, one per boiler, read each one's pressure. A built-in 3.5-liter tank keeps the machine self-contained on water, with a fixed connection available as an option.

The portafilter and baskets are stainless steel. The manual's daily routine includes backflushing the group with cleaning product and a blind filter, washing baskets and portafilter with water or detergent, and wiping the steam and hot-water wands with a damp cloth after each use; periodically, the boilers need draining and the water tank needs cleaning out. It's a machine for someone who already has grinding, dosing and tamping down, and wants a bar machine's architecture at home.