Understanding Your Commercial Espresso Machine

In this article, we explain the basic features and functions of the components of any commercial espresso machine. Specific operating and cleaning procedures are explained in our other articles.

Groups, Group Handles, and Filter Baskets

A commercial espresso machine will have one or more "groups," which are also sometimes called "groupheads." A group is the place where the group handle is inserted. The group handle holds the filter basket (also called a portafilter) into which the ground coffee is placed.

The group handle with the filter basket and coffee is inserted into the grouphead, and locked into place with a slight twist of the wrist so as to enable you to do an espresso extraction. The extraction is controlled by switches on the front panel.

Control Switches and the Manual Override for Each Group

For a semiautomatic espresso machine, a switch or lever on the front panel will be used to both start and stop the pressurized flow of water into the grouphead for an espresso extraction (also called a "shot"). For a fully-automatic espresso machine, the espresso shots are preprogrammed. There will be a different switch for each shot size (a single and a double, and perhaps one or two more) for each group. All that the operator needs to do is to push the correct button to do an extraction.

In fully automatic commercial espresso machines, there will also be a manual override switch. This is basically the same control switch as is on a semiautomatic espresso machine. It will allow you to manually turn the pressurized flow of water into the group on or off. The manual override switch is used when you clean the espresso machine, and it is generally used to set the shot sizes when programming the automatic controls on your espresso machine. The manual override switch is also used to wash the group handle and filter basket prior to putting in fresh grounds for the next shot.

In espresso shops in which your staff will not be professionally trained, we recommend that you get a fully automatic espresso machine. This allows you to preset the shot sizes of your espresso and your operators do not need to guess at the appropriate shot size, particularly if they are not professionally trained baristas. The shot size will effect the intensity and flavor of the shot. For reproducible and reliable espresso quality (which should be a "trademark" of any commercial espresso shop), it is best to use preprogrammed shots.

Steam Wands and Pressure Gauges

A commercial espresso machine will have one or more steam wands, which are used to froth and steam milk. There is a steam valve above each wand which you will open (or close) to produce steam (or not). On many commercial espresso machines, the tip of the steam wand will be threaded onto the wand, and is removable (by hand-unscrewing it) to enable a more thorough cleaning.

There will be one or more pressure gauges on the front panel of the espresso machine, which indicate the pressure within the boiler (which will produce the steam), as well as the pressure that will drive the extractions within the groups. You should not attempt to froth milk or extract espresso until these valves indicate that the pressures are adequate.

The Power Switch and the Voltage

On a related note, every commercial espresso machine has a power switch that will shut down the heaters (and everything else) overnight. Whether you choose to do this is a matter of convenience, and of "wear and tear." The good thing about shutting the machine down is that then the steam valves can be left open for the night so that the internals of the machine do not remain under pressure.

But in the morning, you must arrive well before opening up to allow the boiler enough time to heat up. The main reason that commercial espresso machines (or at least the ones with large boilers) run on 220 Volts is that the higher voltage will allow the boiler to heat more quickly. As an option, we allow our smaller commercial espresso machines (the La Pavoni Pub line) to be converted to 220 Volts.

Some of our customers ask whether we can convert 220 Volt commercial espresso machines to 110 Volts, so that they don't need to pay an electrician to install a 220 Volt circuit. The answer is that we can do this for them for some espresso machines (for an additional charge), but we generally recommend against doing it. In the first place, our cost to do this is comparable to what an electrician would charge for putting in a new circuit (in most situations). But there is a more fundamental reason.

While running at 110 Volts may be OK for the high-end homeowner who wants to install a commercial espresso machine in the pantry, it will take a 110 Volt commercial espresso machine a very long time to heat up - perhaps an hour. Most commercial shops will not want to wait this long to open for business.

The Hot Water Dispenser

A commercial espresso machine will have a hot-water dispenser, usually next to one of the groups, or between groups. A hot water valve on the front panel will allow you to turn the dispenser on to get boiling water directly. Of course, the boiling water is needed for tea, to make Americanos (also called "Lungos") - in which espresso is diluted with hot water, for cleaning purposes (e.g., water to soak things in overnight), and to heat cups if they are not already hot from the heating tray.

The Heating Tray for Your Cups

On the very top of the commercial espresso machine (and also on many super automatic home espresso machines) is a heating tray. This is a flat surface with railing around it onto which your clean cups should be stored, face down. The heating tray will keep the cups warm, so that when you extract espresso into one of them, the espresso will not be immediately cooled by the cup itself (which would be bad and amateurish). The cups are stored face-down simply so that dust (and other things) do not wind up in them during the course of a day.

The Drip Tray and Drain Hose

At the bottom of a commercial espresso machine - below the groups and steam wands and hot water dispenser, is the drip tray, which will have a grating over it. The drip tray is (obviously) there to catch all of the fluids that do not make it into the cups: spilled espresso and coffee, hot water, etc.

The drip tray will have a drain hose that will run into a catch basin (perhaps a bucket) located beneath the machine (which must be emptied periodically), or it will run to a floor-drain near the machine. Many zoning boards will require a floor drain in commercial establishments. You should check with your local zoning board to see if this is required.

Please consult our other articles to learn about operating and cleaning your commercial espresso machine.