How Does An Espresso Machine Work? Detailed Process

An espresso machine is an innovative piece of equipment with a simple but effective design. It’s a device whose primary function is to make espresso and coffee. But how does an espresso machine work? It’s pretty simple. 

First and foremost, a quick review of all parts of the machine and their definition is momentous. Stay tuned, and let me throw a light on this topic.

What Is An Espresso Machine?

Besides all information about espresso, any coffee lover will have an insatiable curiosity about the machine’s operation. This machine pushes hot water under pressure through closely packed coffee grounds to brew 1-2 ounces of espresso. Thus, it is the so-called coffee brewing appliance. 

Interestingly, this high-pressure technique gives espresso the caramel-colored crema – the top layer of foam and peculiar creamy mouthfeel.

Nothing is more significant than reading the page-turner and sipping a cup of coffee in the me-time at home. That’s the bomb!

Specific machines enable you to tinker with variables and polish your skill to make your awe-inspiring drinks like a powerful ristretto or a sippable lungo. 

The most awaited section is yet to come. Let’s head for the anatomy of espresso machine in the following parts.

How Does An Espresso Machine Work

How Does An Espresso Machine Work?

How do espresso machines work? To grasp the answer, having insights about parts of an espresso machine and how they operate is part and parcel of making enticing coffee. 

Get started with the water flows in most machines! To make a tasty espresso, water must undergo four distinct phases like this:

Water Source -> Pump -> Boiler -> Group Head/Steam Wand

Then, walk through a list of ten significant components in a machine:

The Water Tank (Reservoir)

Any espresso machine requires water. Typically, home espresso makers employ water from a reservoir or a plumbed water supply.

The using purpose determines the water source in the system. Machines producing a few high-quality espressos and lattes daily have reservoirs. A reservoir lets you adjust the water quality without beginning with tap water. 

Meanwhile, larger residential and commercial machines making hundreds of beverages daily need a steady supply of fresh water. They adopt plumb and employ softening technique (for hard water) and filtration instead of reservoir refills.

The Pump

Machines require 9 bars of pressure, or 130 psi, to force water through finely-ground coffee. Most current makers use electric pumps. Home espresso pumps are either vibratory or rotary veins.

Vibratory pumps (vibe pumps) are small-size electromagnetic workhorses. A metal coil contains a magnet-attached piston. The electrical current across the coil pushes the magnet to pull water through the device. 

Rotary pumps come with a complicated mechanism. A motor rotates an offset disc (which is segmented by veins) within a circular chamber. As the spin disc supports, the veins push on the outer chamber wall, causing pressure. As the section narrows down, water is forced out.

Single Boiler

Espresso calls for pressure and hot water, so you need boilers. They help to heat and hold the pressurized water coming from the pump. Thanks to the boiler, the heated water is roughly 250°F or 120°C. Still, this temperature can drop more or less to the brewing range before touching the coffee grounds. 

Modern devices use an electric heating element. When on, electricity travels through the element, causing heat; when off, it’s inert.

The boiler’s size is significant. Larger boilers consume more energy and time to warm water but deliver more shots at a time.

In machines with single boilers, there is only one heating element combined with two thermostats (one coming with a temp range to brew coffee and the other with a fixed temp to boil water and create steam).

Though this kind of boiler is more affordable, you can’t pull steam milk and espresso shots simultaneously. Also, if you want to switch from espresso to steam milk, you have to wait until the water reaches the ideal temp. 

High-end models use thermostats that can eat roughly 25 ounces of water. On average, you only need a thermostat that can boil anywhere from 12 to 16 ounces of water to have the right temperature espresso.

Double Boiler

Dual-boiler machines feature two separate tanks. One water tank is used for the brewing process, and the other does the same for steaming. Moreover, the two independent boilers let you maintain temperature consistency.

This device allows you to change your water temperature without waiting, making it perfect for espresso shots and steaming milk at once.

Also, the steam wand automatically textures the foam to the coffee, boosting flavor and letting you make Barista-style beverages instantly. You can’t take your eyes off this advanced double-boiler machine at first sight.

How Does An Espresso Machine Work

Heat Exchanger

Heat exchangers, or boiler pipes, are typical in bigger residential and commercial devices. When the flow of water gets into the section, it runs through the tube and warms up.

Since the heat exchanger applies a single boiler which creates the milk-stretching steam, this exchanger produces the optimal espresso-brewing water temperature.

The Steam Wand

Mentioning espresso machines, you can’t miss out on the steam wand. Modern machines incorporate steam wands to steam milk. The steaming process necessitates a little pressure to do it.

After that, the milk needs a little air to cause foam, like lattes get their froth. The steam wand shoots steam via the tip’s holes.

The Group Head

The group head is located on the machine’s front side, where the portafilter locks.

It will pressurize while you draw the espresso shots and open the one-way valve seats. As such, hot water will go through the portafilter to make coffee. The group head has its magic in the art of espresso making.

There are three typical group heads: 

  • E61 Group head: The E61 weighs roughly a hefty nine pounds and takes about 15 minutes to reach the needed temperature yet it keeps this figure quite long. This style often goes with Profitec Pro 700.
  • Saturated group heads: They can easily reach the temperature of boiling water as they are detached from the boiler. It is often integrated in La Marzocco GS3.
  • Semi-saturated group heads: They don’t connect directly with a heat exchanger. Also, it’s cheaper to install and fix when in need. This one is often compatible with La Spaziale LUCCA A53 or Profitec Pro 300.


To learn how to make espresso, you should never look down on the portafilter. Portafilters are handle-mounted filter baskets. Before placing and securing the portafilter, finely ground coffee is tamped in the portafilter baskets.

Portafilters come in different sizes. For example, 53mm-and-58mm ones are the most prevailing; 58mm-and-58mm size is excellent for espresso. Both may use the same amount of coffee with the appropriate portafilter baskets.

Control Panel

The control panel will monitor the machine’s functionality: turn on/off, brew temperature mode, steam mode, and hot water dispensing. The best Espresso machine for beginners should have an easy-to-use control panel.

The operations of machines may be controlled digitally or through switches (push buttons or rocker types) and knobs. Beyond that, several coffee maker models consist of pressure-sensitive switches.

Drip Trays

Some current models feature drip trays at the bottom to catch leaks and keep the coffee machine’s countertop clean. A drip tray often has a grating above. Also, detachable drip trays let the taller mugs, including higher latte glasses, fit beneath spouts.

How Does An Espresso Machine Work

How Do Manual Espresso Machines Work?

You’ve just gone through a list of espresso machine parts names and how they work. Dig deeper inside how the manual models run here:

Spring Piston Lever

A spring within this machine forces water through ground coffee. The user pulls a lever (a shot) to compress the spring. While the lever releases the spring, the heated water pumps through your coffee.

While the spring automates water pressure, the barista may manage pre-infusion time and water volume to pinpoint the exact time to shoot. 

Direct Lever

This type of lever automates pressure with no springs. Only the barista’s “pull” pushes heated water over the coffee ground in this machine. Skilled baristas can adjust the pressure and “feel” the coffee to calculate approximation. 

Semi-Automatic Vs Automatic Vs Super-Automatic

Semi-automatic Machines

As the saying goes, this type of espresso machine is partly programmed to let you know when the coffee is ready for serving. 

Automatic Models

This one has a knack for managing the water level pushing through the coffee. Nowadays, some cafeterias can’t lack a digital machine with top-notch programs and features.

Super-automatic Models

This far-out model will send your coffee aromas to the next level. In other words, this one will even please the most erratic guests and users with its advanced technique.

How Does An Espresso Machine Work

The Bottom Line

How does an espresso machine work? After reading this post, I hope this question is no longer a tricky matter in your mind. Your machine’s longevity and quality depend on your familiarity with its inner workings. 

Knowing the significance of each part and its function can help you sort out problems properly.

Having a machine, you can cut down on time getting to the coffee shop and ensure a steady supply of hot coffee at home. Share my post with other guys as well! ()

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