La Marzocco GS3 AV – Dual Boiler Espresso Machine with Saturated Group Head
It's just after six, the kitchen is quiet, and you slide the portafilter into the group head. One press of a button, the rotary pump hums almost silently, and the first drop emerges – thick, honey-colored, with a crema that slowly closes. What you taste in the cup has a reason: the GS3 maintains such stable temperature that the first shot in the morning tastes just like the third in the afternoon.
The GS3 AV is a machine from La Marzocco's professional modular system, built in Florence – only compact enough for your kitchen. AV stands for Auto-Volumetric: you program your shot volumes, and a button press automatically stops the shot. We at Coffee Coaching Club are partners of La Marzocco and a coffee roastery in one – we know the machine inside and out and roast the beans that go with it.
What makes the GS3 special
The heart of the GS3 is the saturated group head. With an E61 group head – the standard for many home machines – water circulates through a heavy metal head, which only truly heats evenly after a longer warm-up time. With the GS3, the group head is directly connected to the brew boiler and permanently surrounded by hot water. The water hits the coffee grounds at the set temperature – shot after shot, without fluctuation.
Coffee contains over 800 aromatic compounds, and which of them end up in your cup depends on how consistently temperature and pressure penetrate the puck. A one or two-degree difference determines whether a shot becomes round and sweet or flat. In our roastery, we observe that saturated group heads deliver a more refined aromatic profile than E61 – that's our view, one of many.
Additionally, the dual boiler: separate boilers for brew water and steam, both PID controlled. You can brew espresso and steam milk simultaneously, without one function waiting for the other. The steam has enough reserve to make cappuccinos for several guests in a row without the pressure dropping.
At a glance
| Machine type |
Dual boiler with saturated group head |
| Control |
AV (Auto-Volumetric) – programmable shot volumes, PID |
| Brew boiler / Steam boiler |
1.5 L / 3.5 L |
| Pump |
Rotary pump (quiet, linear pressure build-up) |
| Portafilter |
58 mm |
| Water |
Tank or plumbed-in |
| App control |
La Marzocco Home App compatible |
| Casing / Colors |
Stainless steel – Black, White, Silver |
| Weight |
approx. 34 kg |
| Manufacture |
Florence, Italy |
AV or MP
This page is for the AV (Auto-Volumetric) version: you program shot volumes, a button press starts, and the machine stops automatically – good for repeatability and if multiple people use the machine. If you prefer to control the brewing process manually via a paddle and play with the pressure profile, you'll find that in the GS3 MP (Manual Paddle). Both are brilliant machines – it's a question of workflow, not quality.
Who the GS3 is for
Nobody needs a GS3, and that's part of honest advice. There are very good machines for significantly less money. Those who choose a GS3 are looking for the saturated group head in their own kitchen – the thermal stability of a café machine, the mass, the presence on the counter. Those who want that usually know why. The GS3 is a decision, not a compromise.
What goes with it
The grinder makes the biggest difference. Freshly ground coffee determines what arrives retro-nasally in the cup – pre-ground coffee loses in minutes what the bean has built up over months. For maximum precision, it's worth looking at Weber Workshops or Option-O, from the same house the La Marzocco Swan or the more compact La Marzocco Pico. Extraction by weight ratio (1:2 as a starting point) provides the most reliable results – along with a scale from Normcore or with an app and flow rate display from Acaia. Our machine comparison shows which La Marzocco machine suits you.
Ordering, delivery and advice
You can order the GS3 directly online. After ordering, we will contact you shortly to clarify configuration and delivery. Delivery throughout Switzerland and to Liechtenstein in 2–4 working days, Click and Collect in Bern and Zurich. For a machine of this class, we recommend picking it up in the showroom – then we'll go through the machine together. An introductory course (approx. 60 minutes, incl. extraction philosophy) is included with the purchase. Financing possible via Heylight. Questions are welcome via office@coffeecoachingclub.ch or by phone during business hours.
Frequently asked questions
What does AV mean on the GS3?
AV stands for Auto-Volumetric: you program shot volumes, a button press starts, and the machine stops automatically. If you want to control it manually via a paddle, choose the GS3 MP.
What is a saturated group head?
The group head is directly connected to the brew boiler and permanently surrounded by hot water. This keeps the brew temperature very stable – the first shot tastes like the third.
Can I connect the GS3 to a direct water line?
Yes. The GS3 works with a water tank or a direct water line connection. With a direct water line, you never have to refill.
How does the GS3 differ from the Linea Mini R?
Both are dual boilers from La Marzocco. The GS3 has the saturated group head, larger boilers, and more mass. Our machine comparison shows which one suits you.
Can I see the GS3 live before buying?
Yes, in our showrooms in Bern and Zurich. Not every machine is always on site – please contact us briefly beforehand, and we will make it available.
Roastery Tip
The thermal stability of the saturated group head extracts precisely the compounds that create body and warmth from medium roasts. Our Cozy Chocolate shows dense chocolate with a sweetness that builds slowly. Nutty Delight becomes nutty-round, ideal with milk. If you're looking for maximum body without acidity, choose Very Nutty. And if you like to experiment, the light-roasted Wild Peach offers a lively, fruity cup. This is our recommendation, one of many.
